Wetlands, Biodiversity and the Ramsar Convention

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Wetlands, Biodiversity and the Ramsar Convention:the role of the Convention on Wetlands in the Conservation and Wise Use of Biodiversity

CHAPTER 5

THE EUROPEAN REGION

An Overview of European Wetlands

By Tim Jones, Technical Officer for Europe, Ramsar Bureau, Switzerland

Boundaries of the Region

Defining the boundaries of Europe is a difficult task and one which is open to a wide variety of geopolitical, biogeographical and other interpretations. Within the framework of the Ramsar Convention, added complexities arise from the fact that several European Contracting Parties have dependent territories in other regions of the world. However, for the purposes of this publication, Europe is considered to include the area from the Atlantic and northern Mediterranean coastlines to the Ural Mountains, the Ural River and the northwest shoreline of the Caspian Sea. Greenland is excluded, but Iceland, Turkey and the trans-Caucasian countries are included. Within this area of approximately 10 million square kilometres - less than 10% of the world's land surface - are crammed no fewer than 48 independent states, as recognized officially by the United Nations (mid-1995).

Thirty-six of these states are Contracting Parties to the Ramsar Convention, with 16 belonging to the Eastern European Ramsar region and 20 to the Western European region. The two regions were established by the Conference of the Parties in 1987 to reflect the political realities at that time. However, European Contracting Parties have decided to maintain the arrangement to reflect ongoing practical and economic differences, even though the political situation has changed completely.

There are more than 550 Ramsar listed sites designated by European Contracting Parties, with about 450 of these being in Western Europe. However, the larger number of sites in Western Europe should be contrasted with the much larger average size of Eastern European sites, reflecting the generally greater extent of wetland loss and fragmentation in the Western European region.

Wetland losses

Europe's long history of settlement, permanent agriculture and industrialization has wrought huge changes on the natural ecosystems of the region and upon the species of flora and fauna which are an integral part of them. Whilst it can be argued that the activities of people gradually increased the biodiversity of Europe over the course of many centuries, through the creation of an intricate, artificial mosaic of habitats, the more recent past has seen a reversal in that trend. Wetlands have come under particular pressure, with the drainage of extensive lowland areas for agriculture and urban development, and the regulation of major river systems for power generation, water storage, navigation and artificial flood control. For example, up to 95% of Switzerland's original marshland has been drained and converted, whilst the Danube and Volga rivers - the two longest in Europe - have been transformed by the construction of numerous dams. In Greece, the construction of dams and drainage tunnels in the late 1940s and 1950s led to the disappearance of 60,000ha of wetlands and the partial drainage of a further 390,000ha. A recent study of 78 major wetlands in France has found that more than 85% of the sites had been significantly or extremely degraded during the period 1960 to 1990. In Poland, less than 10% of the country's once vast peat bogs remain intact, whilst in Bulgaria, of 200,000ha of wetlands at the start of the century, only 11,000 have survived. Increasingly in the 20th century, various forms of pollution (e.g. eutrophication, contamination with heavy metals and radioactive material, acidification, and salinization) threaten the quality of water in wetlands, whilst over-exploitation of groundwater resources in many areas places the very existence of important wetlands at risk.

The Biodiversity of European Wetlands

In spite of the extensive loss and degradation of European wetlands highlighted above, many important wetlands (at international, national and local levels) remain, albeit many of them highly fragmented and much altered in comparison with their original condition. The present-day distribution of wetlands in Europe naturally reflects biogeographical controls such as climate, geology and soil types, but has also been determined by the political and economic differences which have divided the continent for much of the present century.

Taking biogeographical factors first, the variety of European wetlands ranges from coastal lagoons supplied by winter rains in the Mediterranean lowlands, to seasonally frozen Alpine lakes, and from the estuaries of the northwest Atlantic coast to the extensive peat bogs and forested wetlands of Fenno-Scandia and eastern Europe. Central Europe is characterized by lake and river floodplain systems, with seasonally inundated alluvial forests. The northwestern seaboard of the region enjoys the climatic amelioration offered by the North Atlantic Drift Current (or 'Gulf Stream'), whilst the continental climate of the east European steppe zone gives short, very hot summers and bitterly cold winters.

Turning to anthropogenic factors, wide differences can be seen between western Europe and central/eastern Europe and between northern and southern Europe. In general terms the concentration of economic wealth and highly developed industrialization in north and west Europe has seen the greatest loss, degradation and fragmentation of wetlands. Conversely, in central and eastern Europe, and in Fenno-Scandia, the lower degree of industrialization, urbanization and intensive agriculture means that far more extensive areas of natural or semi-natural wetlands remain. The recent political changes, however, and the further changes which are likely to result in the future - for example, the expansion of industrialized agriculture in the region - place the continued survival of many of these intact (or nearly intact) wetlands in doubt. In the south of Europe, the long history of occupation and often intensive use of Mediterranean wetlands place these areas under special stress, which in many recent years has been exacerbated by low winter rainfall.

In world terms, Europe has a rather small share of global biodiversity, with only about 15% of the total estimated number of animal and higher plant species in existence, reflecting the relatively harsh climatic conditions across most of the region. However, this rather modest diversity forms an important component of the whole, with its own intrinsic value. A typical European, nutrient-rich wetland system could be expected to support a range of simple plants (algae, mosses, etc.), flowering plants, invertebrates, fish, amphibians, reptiles, birds and mammals. Of the animal groups, birds are perhaps the most obvious and best known - a point reflected in the case studies.

The biological productivity of European estuaries is remarkable in global terms, with the constant renewal of nutrients by tidal action supporting phenomenal densities of invertebrates, in turn supporting commercially important fisheries and millions of migratory waterbirds. The Atlantic and North Sea coasts are especially important, with the United Kingdom alone having 163 estuaries.

Like other regions, Europe supports species which are found nowhere else on Earth. Amongst endemic species found at European wetlands of international importance are the fish Barbus prespensis, found only at Lake Prespa in Greece. Because of the pressures on natural ecosystems in Europe, a very high proportion of species are considered to be under threat. This is certainly true of wetland species, which depend on habitats which have been highly fragmented and degraded (for example, around a quarter of all fish species and nearly one half of all amphibians in Europe are considered threatened). A recent BirdLife International study of population trends in European bird species concluded that a quarter of all declining species had been adversely affected by wetland drainage. The European Otter (Lutra lutra) has been extirpated from much of western and central Europe, whilst intensive agricultural practices mean that many wetland plants (e.g. certain species of orchids) are becoming more and more confined to nature reserves and other protected areas. In the Netherlands, it has been estimated that 30% of all species require a high water table. However, in many parts of the country, water tables have fallen substantially as a result of groundwater being extracted for use in industry and drinking water supply, and because of more efficient drainage and irrigation.

The Many Values of European Wetlands

Wetlands in Europe, as elsewhere in the world, include highly productive systems, notably estuaries, which provide the plants and invertebrates which form the basis of complex food chains, in which human beings are often the 'top predator'. Wetlands in the region sustain major fisheries and shellfisheries, and provide grazing for livestock. In central and eastern Europe, wetlands continue to provide economically important plant products such as the Common Reed Phragmites australis and willow Salix spp. which are utilized by local communities.

Europe's wetlands also provide food, shelter and nesting or wintering grounds for millions of migratory birds which undertake seasonal migrations to and from other regions, including Africa, the Middle East, Greenland, Arctic Canada and Siberia. These include true water birds, such as ducks, as well as many other wetland-dependent species, such as Osprey Pandion haliaetus and a wide variety of small songbirds. Amongst the many wetlands which are ecologically linked with Europe in this way are two of the sites described in other chapters of this publication: Djoudj National Bird Park in Senegal, West Africa; and the Azraq Oasis in Jordan.

Finally, wetlands play an important role in recreation, be it of an informal kind, or part of the highly developed European tourism and leisure industries. Swimming, sailing, fishing, bird-watching, hiking and hunting are just some of the economically important activities which rely on maintaining a healthy wetland environment.

The Case Studies

The case studies which follow introduce a snapshot of part of the biological diversity and productivity of European wetlands outlined above, as well as illustrating a range of factors which may lead to the loss or degradation of some of this diversity and productivity.

The Ebro Delta in northeast Spain illustrates the diversity of Mediterranean wetland types and species, and the importance of ensuring the conservation and wise use of sites which maintain the ranges of species which have disappeared elsewhere. However, the delta is under pressure from (amongst other factors) sediment starvation as a result of dam construction upstream, abstraction of river water leading to salinization and eutrophication, pollution by pesticide run-off from intensive agriculture, and tourism development.

The case study chosen to represent the situation in central Europe is the extensive transboundary lake (and other associated wetlands) shared by Austria, where the lake is known as Neusiedlersee, and Hungary, where the name Fertó is used. The site includes a diversity of wetland types, and supports an especially extensive area of reeds which, in turn, support important populations of nesting birds. International restoration measures are currently under way to counter the adverse impacts of the artificial lowering of the water table through past drainage and irrigation.

The extensive peatlands of northern and eastern Europe are represented by Teici and Pelecare Bogs in eastern Latvia. More than 600 higher plant species and 2,800 animal species (including over 2,500 invertebrates) have been identified at the site, which is composed of a mosaic of different wetland habitats. Factors which influence the site adversely include intensive forestry and drainage of surrounding land for agriculture.

The Norfolk and Suffolk Broads case study, from the United Kingdom, is an example of the rich biological diversity and productivity which has arisen in an essentially cultural landscape. The wetland habitats and species now found in the region are the result of centuries of manipulation by local communities for fuel production, wetland plant products, and extensive summer grazing. Maintenance of the area's biological value depends on the continuation of traditional management practices, combined with measures to restore damaged habitats and to counter eutrophication from sewage and agricultural run-off, as well as the effects of mass tourism, and, in the longer term, rising sea levels.

It would have been equally possible to choose many other combinations of case studies to reflect other aspects of the biological diversity and productivity of Europe's wetlands and the challenges which are faced in trying to maintain, and, where necessary, restore these values. For example, estuaries, major river systems, mountain wetlands and Arctic wetlands are not included.

The case studies selected all happen to feature wetlands which are protected areas. However, site protection measures - such as the designation and management of nature reserves - alone, will never succeed in maintaining the biological diversity and productivity of the region's wetlands. They may preserve the 'crown jewels' as living museums, but site-based measures can only be extended to a tiny minority of wetlands. Perhaps the most important task is to ensure that policies dealing specifically with wetlands are incorporated within the general environmental action plans and conservation strategies being drawn up at regional, national and supra-national (e.g. European Union) levels. Conservation and wise use of the vast majority of European wetlands has to be achieved through wider policies such as integrated planning and management for whole river basins, and adequate consideration of wetland issues by the agricultural, industrial and transportation sectors.

The Role of the Ramsar Convention

The Convention has a long history in Europe, having been initiated largely by European conservationists concerned by the rapid loss of wetlands habitat critical to the survival of migratory waterbirds. Nowadays, Ramsar plays a prominent role at many levels, both within particular states and internationally. Amongst the regional initiatives that the Convention participates in are the Pan-European Biological and Landscape Diversity Strategy established under the ministerial 'Environment for Europe' process, and the 'MedWet' initiative - supported largely by European Union funding - for the conservation and wise use of Mediterranean wetlands.

The Convention aims to maintain close working links with the many national, regional and international organizations - both governmental and non-governmental - active in Europe. Amongst these are the European Commission, Council of Europe, Barcelona Convention, Berne Convention, Bonn Convention (and related Agreements, especially the Agreement on African-Eurasian Migratory Waterbirds), and the regional and country offices of BirdLife International, IUCN-The World Conservation Union, Wetlands International, and World Wide Fund for Nature - WWF.

The Convention has been able to provide - or act as the conduit for - modest funding for wetland projects in countries of central and eastern Europe whose economies are in transition. From 1997 onwards, these states will also have access to the Ramsar Small Grants Fund mechanism; it is hoped that this will ensure ongoing practical assistance for wetland conservation and wise use in the region.

 Note: In the European case studies, "Species of European Conservation Concern" refers to BirdLife International's classification of European birds according to their global and European status; it indicates here species with an unfavourable conservation status in Europe (i.e. those in categories 1,2 and 3).

Further Reading

• Dugan, P.J. 1993. Wetlands in Danger. IUCN, Gland, Switzerland.
• Finlayson, C.M. and Moser, M.E. (eds). 1991. Wetlands. International Waterfowl and Wetlands Research Bureau, Slimbridge, UK.
• Jones, T.A. (ed). A Directory of Wetlands of International Importance. Part III, Europe. Ramsar Convention Bureau, Gland, Switzerland.
• Stanner, D. and Bourdeau, P. (eds). 1995. Europe's Environment - The Dobris Assessment. European Environment Agency, Copenhagen, Denmark.
• Tucker, G.M. and Heath, M.F. 1994. Birds in Europe: their Conservation Status. BirdLife International, Cambridge, UK.

Case Study 1: Austria/Hungary

Neusiedlersee/Fertó

By Gerald Dick, World Wide Fund for Nature (WWF), Austria

General Description

Neusiedlersee is situated at the lowest point of the Little Hungarian Plain and is Europe's westernmost steppe lake. Because of this special situation in terms of biogeographic regions, the biodiversity of the area is characterized by a mosaic of different habitats such as the lake itself, numerous small, shallow alkaline lakes, wet meadows, reed-beds, saltmarsh-like inland vegetation, fen and grasslands. The lake covers an area of 320km2 whereas about 180km2 are covered with the Common Reed Phragmites australis. Until the mid-seventies there was a huge belt of macrophytes in front of the reed (mainly consisting of Fennel Pondweed Potamogeton pectinatus and Spiked Milfoil Myriophyllum spicatum) which disappeared after the introduction of the alien Grass Carp Ctenopharyngodon idella. Right now the plants are slowly recovering due to the natural death of these fish.

Current Status of Neusiedlersee

Various attempts have been undertaken to document the internationally important situation of this wetland site. Under the Bern Convention the site was nominated as a Biogenetic Reserve under the auspices of the Council of Europe. In the framework of the Man and Biosphere Programme, Neusiedlersee was declared a Biosphere Reserve. In 1982 it was declared a Ramsar site and in 1992 a National Park; additionally at the moment it is also proposed as a World Heritage site.

Biological Diversity

The Ramsar site is shared between Austria and Hungary with the greater part, measuring 60,000ha, situated in Austria and the remaining 2,870ha in Hungary. Apart from the strikingly flat landscape which, however, contains diverse ecological units, one mainly thinks in terms of waterbirds when talking about Neusiedlersee. The reed belt, with a maximum width of 12km, holds breeding populations of Purple Heron Ardea purpurea (100 pairs), Spoonbill Platelea leucorodia (15 pairs), and Bittern Botaurus stellaris (200-300 pairs), which are considered Species of European Conservation Concern, as well as a number of other species (see Box 7).

The Seewinkel, east of the lake, is famous for its roosting migratory geese such as the Bean Goose Anser fabalis (up to 30,000), Greylag Goose Anser anser (up to 6,000) and White-fronted Goose Anser albifrons (up to 12,000). It is also noted for the waders breeding and roosting in and at the edge of the small lakes including approximately 100 breeding pairs of Avocet Recurvirostra avosetta, 20 pairs of Kentish Plover Charadrius alexandrinus and 8 species of breeding gulls and terns. Thirty species of waders and 21 waterfowl species (geese excepted) are frequent migrants, and 13 waterfowl species and Greylag Geese breed regularly.

However, when talking about biodiversity the special situation of the vegetation must also be mentioned. Specialities not only for Austria but even for Europe can be found. Lepidium cartilagineum for instance covers an area of distribution as far as from the Ukrainian steppes to its western border at Neusiedlersee. Another rarity is Artemisia laciniata, a species of Central Asia which has its only proven locality in Europe at Neusiedlersee. 

Wetland Losses and Current Threats

After some glimpses of the jewels of the area some negative factors have to be mentioned. Due to so-called improvement and drainage measures, the water surface of the shallow lakes east of Neusiedlersee diminished from 3,615ha in 1855 to only 805ha in 1986. Also the typical 'puszta' pastures (dry grassland) were changed into arable land. The intensification of agricultural land-use led to extensive eutrophication, easily visible in terms of algal blooms and reed expansion (1,009ha in 1855 versus 3,016ha in 1993) as well as the occurrence of botulism in waterfowl (over 2,000 dead birds in 1982 and again 1983, although in 1992 only 641 carcasses were collected).

Furthermore, groundwater resources are used for irrigation purposes and even maize fields and vineyards are watered. Together with the effect of numerous drainage canals, the lowering of the groundwater level and the decline in salinity pose major threats. The drying out of large lakes and the disappearance altogether of some lakes due to the lack of water is a serious problem. Attempts are now being made to build sluices on the old canals in order to reduce the run-off speed of the water and to restore the water balance. On Neusiedlersee itself attempts have been made to raise the water level because of the effects of an artificial outflow which was built in 1910.

The creation of the transboundary National Park helps to promote wetland restoration and it is hoped that wise use of the whole Ramsar site can be achieved in the near future to maintain and manage the biodiversity and resources of the area.

Further Reading

• Dick, G., Dvorak, M., Grüll, A., Kohler, B and Rauer, G. 1994. Vogelparadies mit Zukunft? Ramsar - Gebiet Neusiedler See - Seewinkel. Umweltbundesamt Wien.

 Case Study 2: Latvia

The Teici Reserve

By Ugis Bergmanis, Teici State Nature Reserve, Latvia

Location of the Reserve

The Teici Reserve is made up of the Teici and Pelecare Bogs, situated in the eastern part of Latvia within the regions of Madona, Jekabpils and Preili. The total area of the territory covers about 24,000ha, and it was designated as a Ramsar site on 5 April 1995. Both bogs are typical for Eastern Latvia. The Teici Bog has been a State Nature Reserve since 1982 while the much smaller Pelecare Bog has been a restricted Nature Area since 1977.

Management Organization

Most of the area (19,047ha) is included in the Teici State Nature Reserve - one of Latvia's five nature reserves and the largest. The area is administered and managed by the Nature Reserve which has a status of state institution and, since 1994, has been administered by the Ministry of Environmental Protection and Regional Development. The reserve is state owned and is included in the list of specially protected nature territories which cannot be privatized.

High altitude peatland and associated lake at the Teici Reserve, showing typical peatland vegetation. (Photo: Ugis Bergmanis)

About 80% of the Teici Reserve is covered by a high bog in an almost untransformed state. This is the largest high bog in Latvia and one of the largest in Europe. As a result of its characteristics this area is recognized as an IUCN Management Category I: a protected area managed mainly for science or wilderness protection. The reserve area is divided into two zones and in one of these, covering about 4,800ha (25%), no human activities other than those connected with research are permitted. In the remaining area of 14,247ha (75%) some management activities are permitted such as limited regulation of animal numbers and erection of artificial nest platforms for rare bird species; local inhabitants are allowed to continue their traditional activities of gathering firewood and wild berries.

An area of 20,000ha has been established as an outer protection zone around the territory designated as a Ramsar site. To prevent activities which could have a negative effect on the ecosystems of the reserve and to promote nature protection in the outer protected zone, small restricted areas around nest sites of Black Stork Ciconia nigra and rare raptor species have been established in this area. Hunting of Black Grouse Tetrao tetrix, Capercaillie Tetrao urogallus and geese as well as use of pesticides is prohibited. Treaties between private landowners and the Teici Reserve will be concluded in the future concerning the use of land and natural resources. In order to preserve ecosystems in their natural state some regulation of hydrological conditions in ditches flowing out from the bog as well as haymaking on natural meadows is planned.

Ecological Description ofTeici

The reserve is situated in the central part of the East Latvian lowlands, its absolute height lying between 97m and 113.4m. The Teici Bog is located in the mixed forest sub-zone of the temperate forest region. The area is not densely populated with an average density of 4 people per km2.

Most of the territory is covered with bogs (ca 15,257ha or 80%) and although around 95% of these are high bogs there are also small areas of transitional and low bogs in some places. Within the bog ecosystem, 206 bryophyte and 672 vascular plant species have been found. Lakes, morasses and pools of different size are typical of the bog and there are 18 lakes larger than 2ha covering a total area of about 380ha. Around the bogs, different sized forest stands cover an area of about 3,729ha (20%) and mineral soil islands and peninsulas inside the bog are also covered with forests. Some 97% of total forest area is natural forest. The dominant tree species are Scots Pine Pinus sylvestris (ca 51%), Silver Birch Betula pendula (ca 33%) and Norway Spruce Picea abies (ca 12%) mixed with Aspen Populus tremula and also Common Alder Alnus glutinosa, Common Ash Fraxinus excelsior and Small-leaved Lime Tilia cordata. These are mainly middle-aged stands. Most widespread are the forests on drained peat soils, dry mineral soils and wet peat soils although there are small areas of forest growing on wet and drained mineral soils.

The diversity of habitats accounts for the considerable diversity of the fauna - 2,837 animal species have been found there. Most of them are invertebrates (2,596 species) with arthropoda the best investigated group (2,553 species). Vertebrates are represented by 41 species of mammals and 186 species of birds. The list of mammal species found here includes several species considered threatened in much of Europe such as the Beaver Castor fiber, Lynx Lynx lynx, Grey Wolf Canis lupus, Brown Bear Ursus arctos and Otter Lutra lutra. Of the bird species which have either been found nesting or are thought to be nesting, 15 are considered Species of Europe Conservation Concern, including: Black- throated Diver Gavia arctica (2-3 pairs); Black Stork Ciconia nigra (3-5 pairs); Short-toed Eagle Circaetus gallicus (1 pair); Lesser Spotted Eagle Aquila pomarina (3.5 pairs per 100 km2); Golden Eagle Aquila chrysaetos (one probable breeding pair); Peregrine Falco peregrinus (one probable breeding pair); Black Grouse Tetrao tetrix (common breeding species); Crane Grus grus (15-32 pairs); Black- tailed Godwit Limosa limosa (8-16 pairs); Wood Sandpiper Tringa glareola (48-97 pairs); Nightjar Caprimulgus europaeus (breeding); Three-toed Woodpecker Picoides tridactylus (breeding); Green Woodpecker Picus viridis (breeding); Grey-headed Woodpecker Picus canus (breeding); Osprey Pandion haliaetus (1-2 pairs). Other important breeding species are listed in Box 8.

The Teici Bog and surroundings are also extremely important as stop-over and feeding sites for passage geese and cranes. During the autumn migration period about 1,200 Cranes, 4,000 White-fronted Geese Anser albifrons and 4,000 Bean Geese Anser fabalis have been observed simultaneously.

The Pelecare Bog

Covering an area of 4,546ha, this bog is located to the south of the Teici Bog. A rather high diversity of habitats is also typical for this bog-forest complex. Although this territory has not been so well investigated it seems a very important site for passage Cranes and geese as well as for the protection of bird species typical of bogs.

Threats to the Teici and PelecareBogs

The peripheral part of the Teici Bog is badly affected by the development of surrounding agricultural lands as well as ditches flowing out from the bog. Most affected are moist forest stands where mineralization of their peat soils has transformed growth conditions of the forests; a rather similar situation has been observed on the areas surrounding the Pelecare Bog. As the laws relating to the reserve area do not cover these territories, the forests around the bog are intensively utilized thus altering the habitat and the diversity of species.

Case Study 3: Spain

The Ebro Delta

By Albert Martinez Vilalta, Parc Natural del Delta de L'Ebre, Spain, and Francesc Giró, Department of the Environment of the Generalitat of Catalonia, Spain

General Description

The Ebro Delta is one of the major river deltas of the Mediterranean Basin. It covers an area of 320km2 and consists of a typical delta platform extending 30km into the Mediterranean. The main surface of the delta is covered by agricultural land, and most natural areas are located along the edges, behind large natural beaches and sand dunes. Two sandy lobes extend from the main delta enclosing large bays of shallow water where shellfish production is very high. Natural habitats include also coastal lagoons, salt and freshwater marshes, salt pans, freshwater wells and small remnants of riparian forests. The Ebro Delta is considered of European importance for its saltmarsh and aquatic vegetation and for its waterbirds, with 40,000 breeding couples and more than 180,000 wintering birds. It is also an important area for fisheries in the western Mediterranean.

Natural water wells at the Ebro Delta - an interesting freshwater habitat typical of Spanish Mediterranean coastal plains close to karstic countryside where underground water overflows. (Photo: Anna Motis)

Current Status

At present, the main remaining natural areas covering 7,736ha are protected as a Natural Park and a further 3,794ha are included in the Catalonian Plan of Areas of Natural Interest (PEIN). The Ebro Delta is a Ramsar site and also an Important Bird Area, as identified by BirdLife International. It is also being considered for inclusion in the European Union's Natura 2000 Network of important conservation sites. Within the park, there are 4,400ha where hunting is strictly forbidden and fishing is not permitted in a 900ha sector. The PEIN provides basic protection to some other areas including a buffer zone of rice fields around lagoons. Almost all of the coastal areas are public land while nearly half of the lagoons and marshes are private property. A Zone Plan is being developed to reduce the impact of agriculture in aquatic ecosystems and to guarantee the continuity of rice production in the delta.

Utilization

Because the Ebro Delta is heavily populated compared to other Mediterranean wetlands, the area is intensively utilized. There are very few areas where the natural resources are not exploited. In most of the delta, agriculture is the main activity and this includes intensive rice production covering 21,500ha and in some areas other crops such as lettuce, tomato, and melon. In a couple of relatively small areas, there is some extensive cattle ranching allowing the development of interesting habitats. Fishing is very important both in the lagoons, river and surrounding sea. Shellfish production is also remarkable in the enclosed bays of La Banya and El Fangar. Aquaculture is becoming important in some areas including both extensively and intensively managed systems. Waterfowl hunting is very popular in the area with over 5,000 hunters. Finally, tourism development, concentrated at the moment in the resorts of Riumar and Eucaliptus, is likely to spread to other areas.

Major Threats

The Ebro Delta is a heavily populated area with over 50,000 inhabitants. This, together with the lack of an overall integrated management plan for the whole area, creates a complex situation. The main threats are as follows:

-- subsidence of the delta plain and serious local erosion of the coast due to the almost complete reduction in the sediment loads of the river, retained upstream in dams;

-- river flow has been reduced due to the intensive use of water, mainly in the summer, resulting in salinization and eutrophication. If the proposals of the 'Plan Hidrologico Nacional' go ahead, these reductions could be much worse;

-- heavy water pollution because of intensive agriculture. This is mainly due to the use of pesticides, but also because of nutrients causing eutrophication of some lagoons;

--improvement of the irrigation system by transforming natural ditches into concrete channels and by setting up drainage pumps. This has very negative effects upon the water table and upon fish and invertebrate populations;

-- intensive use of natural resources, leading sometimes to overuse (hunting, fishing, harvesting of natural shellfish stocks);

-- development of the area for tourism. This is already degrading some of the beaches and there are constantly new development proposals;

-- reclamation of natural areas to develop intensive aquaculture projects. This is becoming important in some areas.

Habitats and Species of Particular Interest

Most of the typical Mediterranean wetland habitats are present in the Ebro Delta except for a few types such as riparian forest and certain freshwater temporal marshes. As far as the flora is concerned, the Ebro Delta is a unique site in the Iberian Mediterranean coast. It is an area of great biogeographical interest with many species having their northernmost or southernmost distribution limits (e.g. Honeysuckle Lonicera biflora; Tamarisk Tamarix boveana, Common Alder Alnus glutinosa). There are also many rare species in aquatic habitats such as Pepperwort Marsilea quadrifolia, White Water-lily Nymphaea alba, and the Lesser Naiad Najas minor, while in sandy and saline soils other rarities can be found (e.g. Limoniastrum monopetalum, Loefingia hispanica, Zygophyllum album, Orobanche cernua, and 10 different species of the sea lavender genus Limonium).

The delta is well known for its animal life. Among invertebrates, molluscs are particularly rich with endemic snails of the genus Melanopsis and the very rare Margaritifera auricularia. There are important populations of endemic fishes such as the threatened Aphanius iberus (IUCN Red List, 1994) and the Valencia Toothcarp Valencia hispanica. There are also some rare reptiles such as the European Pond Terrapin Emys orbicularis, the Spanish Terrapin Mauremys leprosa and two globally threatened species, Herman's Tortoise Testudo hermanni and the Loggerhead Caretta caretta (IUCN Red List, 1994). The Loggerhead has occasionally nested on the beaches.

The delta is particularly important for aquatic birds and especially for its nesting populations of gulls and terns. Outstanding is the world's biggest colony of 10,300 pairs of Audouin's Gull, Larus audouinii, a threatened species (IUCN Red List, 1994). Other species nesting in large numbers in the area are shown in Box 9.  

The delta is also a very important resting, moulting and feeding area for thousands of migratory birds. In the autumn, up to 20,000 herons of different species have been seen, while in the winter peak counts, 100,000 ducks, 20,000 coot and over 30,000 waders are present.

Case Study 4: United Kingdom

Norfolk and Suffolk Broads

By Jane Madgwick, Broads Authority, England

History of the Broads and their Current Status

The Broads is an area where marshes, fens, rivers and lakes intertwine to form a wetland unrivalled elsewhere in Britain. These landscapes have been fashioned by patterns of living and working stretching back over many centuries. In particular the excavation of peat for fuel and the harvest of reed, sedge and marsh hay from the undrained peatlands in the upper and middle valleys have created a great diversity of habitats. The major peat excavations of medieval times have led to the creation of 40 shallow lakes or 'broads', some of which were subsequently connected to the rivers. The river system which is tidal and leads by an estuary to the North Sea, has historically been important for the transport of local goods but in recent decades it has supported a thriving tourist industry based around pleasure boating. Several hundred years ago the majority of the land was reclaimed from the estuary and rivers in the lower valleys. These vast flatlands are maintained by pump drainage and continue to be highly prized summer pastures for cattle and sheep.

The area that receives national protection under the Norfolk and Suffolk Broads Act of 1988 is approximately 303km2 and includes the floodplains and tributaries of three major rivers (the Bure, Yare and Waveney). The Broads Authority, which was established in 1989 to coordinate the management of the area, has duties for nature conservation, public enjoyment and navigation and is the authority responsible for planning. The area includes 27 Sites of Special Scientific Interest (SSSIs) designated under UK legislation. Together these SSSIs make up approximately 20% of the Broads area. They have recently been made into a single European Union Special Protection Area and a Ramsar site. Prior to this, two separate, smaller Ramsar sites had existed in the Thurne and Bure valleys since 1976. The new designations include many of the freshwater broads, the majority of the calcareous fens and the areas of drained marshland that support the best examples of aquatic communities in the drainage ditches. Most of this area has also been recommended by English Nature for designation as a Special Area for Conservation under the European Union Habitats Directive. Outside of these statutory designations there are numerous nature reserves.

Species and Communities of Interest

The Broads support the largest expanse of species-rich calcareous fen in the UK. Approximately 2,500ha remains as 'open' fen, clear of woodland and a further 3,000ha is carr woodland, the most extensive of its type in the UK. The varied hydrology of the fens and the complex history of exploitation for peat, reed, sedge and marsh hay has led to great habitat heterogeneity. There are 53 plant communities in the open fen and over 250 different plant species including the rare Fen Orchid, Liparis loeselii. The fen communities include swamp and sedge beds dominated by Great Fen Sedge Cladium mariscus, tall herb fen, and very wet mires with Sphagnum mosses. The fens are also nationally important for birds such as the Bittern Botaurus stellaris, a Species of European Conservation Concern, and the Marsh Harrier Circus aeruginosus and for a large number of invertebrates that are highly specialized to survive in the fen environment.

Almost 40% of the Broads area is drained marshland. These areas are valued for the extensive ditch network which supports a range of aquatic communities including freshwater and brackish types. The marshes are also nationally important for breeding waders such as Snipe Gallinago gallinago and wintering birds such as the Bean Goose Anser fabalis. Virtually all of the marshland management is supported by the European Union's Environmentally Sensitive Area Scheme (ESA) which enables the traditional practice of extensive summer grazing to continue to the benefit of wildlife and landscape conservation.

Challenges and Strategies

The Broads Authority and English Nature have developed an overall resource profile for the Broads 'Natural Area' which guides the habitat strategies. Appropriate water management is fundamental to all aspects of conservation in the Broads. The three central elements of water management in the Broads are water resources, water quality and flood defence. A major challenge has been to halt and reverse the process of eutrophication in the rivers and broads. Since the middle of this century nutrient enrichment caused by sewage effluent and agricultural run-off has resulted in the near total loss of aquatic life in the rivers and the connected broads. A programme of installation of phosphorus removal plants is well underway at the key sewage treatment works affecting the area. Fifteen years of research and experimental management has resulted in the development of a set of practical techniques which can together trigger the recovery of aquatic life. Considerable investment is now being put into the restoration of some of the major broads. A few broads which have remained isolated from the pollution sources still support some of the most important examples of aquatic plant communities in the UK including Stonewort Chara sp. and Holly-leaved Naiad Najas marina.

The Broads is a fragile wetland with intense visitor pressure in the summer. (Photo: David Burton)

The majority of the Broads waterways are open to public navigation (approximately 200km) and congestion is a problem in the summer months. There are also conflicts with the erosion of riverside vegetation due to boat wash. The Broads Authority controls boat speed and can limit the disturbance of flora and fauna by boats through the use of zoning arrangements in sensitive areas. The development of less damaging forms of boating is also being encouraged.

The key challenges in the conservation of the fens are the maintenance of the groundwater supply, the prevention of excessive flooding with nutrient rich and brackish water and the restoration of open fen in the neglected areas which have been invaded by willow scrub Salix spp. The Broads Authority and English Nature are working together with landowners to devise an overall management strategy for the whole peatland area. An important part of this strategy is to encourage the commercial harvest of reed and sedge dominated communities for thatching. New commercial uses are being developed for fen products that are not suitable for thatching, including harvest for biofuel and the reintroduction of extensive grazing systems.

The whole of the drained marshland is threatened by saltwater flooding due to the deterioration of river walls, increasing storminess in the North Sea and sea level rise. A major flood alleviation strategy is being devised by the National Rivers Authority to safeguard all the interests of the Broads area for the long term. The ESA scheme for the Broads is being further developed to meet the nature conservation objectives for marsh ditches and bird life.

CHAPTER 6

THE NEOTROPICAL REGION

An Overview of Neotropical Wetlands

By Montserrat Carbonell, Technical Officer for the Neotropics, Ramsar Bureau, Switzerland

Biogeographical and Political Boundaries of the Region

The Ramsar Convention is an intergovernmental treaty, and in setting the northern and southern limits for the region, strict biogeographical considerations have been waived in favour of political reality. Thus, for Ramsar, the Neotropical Region is considered to include all countries and their territories in South and Central America and the Caribbean.

From a biogeographical standpoint the Everglades (USA) should be considered as part of the Neotropics, as should the Mexican territory along the Gulf of Mexico and the Pacific coast, including a portion of Baja California. On the other hand, the central montane areas of Guatemala and Honduras would be excluded, becoming part of the Nearctic, i.e. North America, while Tierra del Fuego (Argentina and Chile) would be included in Antarctica.

Wetland Diversity

In a region over 10,000km long and reaching almost 7,000m above sea level, a great diversity of ecosystems and of flora and fauna can be found. Although some areas as well as certain groups of plants and animals have been studied thoroughly, the Neotropics remain rather poorly known to science. In spite of this, it is estimated that some 30% of all vascular plants in the world (estimated to be around 400,000 species) can be found in the Neotropics, of which, 80,000 are endemic to it. Of a world total of some 175 families of birds - which include approximately 8,600 species - 86 are present in the Neotropics and 31 are endemic to it. In terms of its mammals, 25% of the 1,100 world species are found in this region.

Within this richness, wetland ecosystems are equally varied, both in terms of species diversity and abundance. The range is impressive: from the tropical coral reefs of the Caribbean, to the mangroves and marshes of the Pacific coast of Central America and the deltas of the Orinoco and the Amazon rivers, to the lakes and saltmarshes of the snow-dominated Puna or Altiplano, the geysers of the Andes in central western Argentina and the fjordland of southern Chile.

The size of wetlands in the Neotropical Region vary tremendously:

-- the 691ha Mejía lagoons designated a Ramsar site by the Government of Peru in 1992 and of great importance for both migratory shorebirds and as a water reservoir for small farms nearby;

-- the 10 million hectares of the Llanos of Venezuela, a vast wetland mosaic, with slow-flowing rivers and streams, lakes, ponds, marshes and seasonally inundated grassland and palm savanna;

-- the 280 million hectares of the Cuenca del Plata (Parana and Paraguay river basins) which includes 14 to 25 million hectares of the Pantanal, the largest freshwater marsh in the world;

-- the 700 million hectares of the Amazon River Basin, most of it bordered by the world's largest expanse of tropical forest but including also non-forested areas, extensive floodplains and lake systems. In Case Study 4 Luis G Naranjo gives his account of the diversity of wetlands in Colombian Amazonia.

The wide altitudinal range in the region is reflected in the extreme differences between wetlands, their values and the benefits they can provide. The coastal wetlands of Belize, Guatemala and Honduras, which include mangrove swamps, seagrass beds and coral reefs, are an example of the richest wetland ecosystems in terms of number of species. A detailed description of coral reefs is provided in Case Study 3 by Sue Wells. On the other hand, Lake Titicaca (830,000ha), is the highest navigable lake in the world at 3,800m above sea level, and it supports important populations of most of the waterbird species which are associated with the high Andes as well as a rich and diverse endemic fish fauna, including 14 species of Orestias.

A spectacular component of wetland biodiversity in the Neotropics as a region, is the shorebird migration, occurring twice each year (southward around August and northward around February). Millions of individuals of some 40 species travel from their breeding grounds in northern North America along different flyways in search of the rich and highly productive wetlands of the south which will provide them with abundant food during the non-breeding periods of their life cycles. Large numbers concentrate in wetlands along the coast of the Gulf of Panama, the Pacific coast of Colombia and Peru, and along the Atlantic coasts of Surinam and Brazil. Some travel still further south, such as the Red Knot Calidris canutus and the Hudsonian Godwit Limosa haemastica, and reach the shores of Tierra del Fuego, where a Ramsar site has recently been declared to protect Bah’a San Sebastián. Roberto Schlatter explores the diversity of Tierra del Fuego in Case Study 2. Other Ramsar sites of special relevance for the conservation of shorebirds include Paracas (Peru), Lagoa do Peixe (Brazil), Coppenamemonding (Surinam) and Laguna Pozuelos (Argentina). The impressive gatherings of migratory shorebirds are testimony to the richness of the wetlands they use and they are important indicator species of the high productivity found there.

Uses and Values of Neotropical Wetlands

The high productivity of the wetlands results in ecosystems which are not only attractive to shorebirds but also have great potential as fish nursery sites and fishing grounds. This has been of great importance to local and regional economies, past and present. Many human cultures developed along the shores of wetlands in the Neotropical Region, as they did in other parts of the world, and benefited from their plants and animals, respected them and in many cases worshipped the gods that lived in them. Throughout the continent, from Alaska to Tierra del Fuego, pre-colonial cultures followed a similar pattern of use of the natural resources, very close to what we know call 'wise use' or 'sustainable use'.

Little is known about the Carib indians who inhabited the Caribbean islands; all Carib cultures were eliminated and in their place appeared the 'creole mestizo', descendants of mixed blood between Carib indians, blacks and whites. The Kuna and Emberá live in houses built on stilts along the Caribbean and Pacific coasts of Panama and Colombia, in the area known as the 'Tapón del Darién' (Darién Bottleneck). The Ashanincas who live between the Ene and Tambo rivers in Brazil, Colombia, Peru and Venezuela, and the Aguarunas in the Marañón river area in Peru, for example, still use the natural resources like their ancestors, in a rotational manner, but are themselves victims of the excessive human exploitation of both forest and wetland natural resources going on in the Amazon today. The Aymara and Quechua, who live in the heights of the Puna, practised rotating agriculture and farming, while the Uros are still mainly fishermen, living in houses built on rafts made of the Totora Reed Schoenoplectus totora, in Lake Titicaca. This wetland was a 'cultural refuge' area in times when these communities were forced to contract because of invasion and aggression from other cultures.

Wetlands in this region provide resources and perform functions of great value to human beings. In an area with 13 independent countries and some 3,000 islands, islets or cays, the Caribbean is constantly stricken by tropical storms and hurricanes. Here, coastal wetlands (including mangrove swamps, coastal marshes, seagrass beds and coral reefs) play an important role in mitigating the negative impact of these natural phenomena. Two of the largest cities in the region, Buenos Aires and Sao Paulo have developed along the Cuenca del Plata, which provides not only water for human use and industry, but abundant fisheries and wildlife resources and transportation. Because of the low gradient of the land the marshes along the rivers function as water reservoirs, protecting these cities, built (unwisely) along the shores of the rivers, from the negative effects of floods. Wetlands perform another quite different function in Costa Rica: on both Caribbean and Pacific coasts, wetlands here attract thousands of tourists each year who come to watch colonies of nesting waterbirds and the arrival of thousands of turtles which lay their eggs in the intertidal zones of their beaches.

Among the many natural resources exploited by man which are generated by wetlands in the Neotropics, are the Cuban Crocodile Crocodylus rhombifer in the Ciénaga de Zapata (Cuba) and the Capybara Hydrochaeris hydrochaeris in the Llanos of Venezuela, which have been sustainably harvested for several decades now. In contrast, mangrove trees provide timber and tannins throughout their distribution areas, but have seldom been harvested in a sustainable way.

It is important to emphasize that human exploitation of wetlands is not necessarily synonymous with loss of biodiversity: sustainable practices over the centuries have maintained wetland biodiversity. One interesting study on use of wetlands, related in case study 5, documents the role of grazing cattle in maintaining the biodiversity of the seasonal marsh at Palo Verde: removal of grazing cattle resulted in significant losses in biodiversity.

Threats to Neotropical Wetlands

From a global perspective, it could be said that many South American wetlands are still in fairly good condition, in contrast with the highly modified wetlands of Central America and the intensively exploited or altered ones in the Caribbean.

Caribbean wetlands are probably some of the least known, least protected and most threatened wetland types. Threats to the integrity of these fragile wetland ecosystems include: use of mangrove trees for charcoal and tanning; waste-dumping; land reclamation and conversion to shrimp ponds; overfishing; and uncontrolled and inappropriate tourism activities around coral reefs. Excessive erosion, sedimentation, pollution and human disturbance are the result. In addition, coral reefs have been going through a bleaching process for a number of years in the Caribbean, which might be related to the increase of the sea-water temperature. Recent studies indicate that, in some areas, as much as 40% of coral reef cover has been lost due to bleaching and to the negative effects of human activities.

In spite of the many functions performed by these coastal wetlands such as storm and flood mitigation, retention of nutrients, shoreline stabilization, and tourism, and the many products generated such as forestry and wildlife resources, and fisheries, few wetlands in the Caribbean have any sort of protection, let alone management plans within the context of the wise use of water and wetland resources.

The narrow strip of land between South and North America, which constitutes Central America, is divided by its central range of mountains and, although the wetlands of the Pacific and Atlantic slopes have quite distinctive features, they experience similar problems. Wetlands on both sides still support a wide range of uses by local communities, but war in the past decades, deforestation in hills and mountains, unwise agricultural practices including uncontrolled use of dangerous agrochemicals, reclamation of wetlands for agriculture (mainly rice, banana and sugar cane) and other farming activities, are some of the major threats to which these wetlands are exposed. In spite (or because) of the small land surface on which they are found, these wetlands are unique and of great value. Human population - mainly settled in the central highlands - was relatively stable until recent times, and lately, with population growth on the increase, peace settled in the region, and a relative economic stability, most Central American countries are looking at tourism as a new source of income to boost their economies. But tourism, if not strictly controlled and regulated, could damage or even destroy the resource upon which it depends.

South American wetlands share most of the problems with Central America and the Caribbean. However, in a thinly populated continent (where most humans are concentrated in a few, very large cities), but where countries have enormous foreign debts, governments are trying to attract large financial investments and develop liberal economic policies, sometimes putting development and conservation into serious conflict. In most cases development policies do not take wise use of resources into account, and in a continent where many civilizations have used natural resources in a sustainable way for centuries, megaprojects are becoming the major threat to wetlands. A few examples illustrate this: the Yaciretá and Itaipú megadams on the Paraná River have changed the waterflow regime downstream, fish migration has been affected and fish species originally separated geographically are now mixing; the Hidrovía proposal, if carried out, would involve a modification of the Paraguay River to make it navigable upstream at a level where the Pantanal would be altered; the wetlands of the Darién (between Colombia and Panama) will be threatened if the Panamerican highway is constructed; Laguna Colorada in the Puna of Bolivia, one of the most fragile ecosystems of the world, is threatened by a geothermal project if environmental considerations are not taken into account.

Conservation Efforts and Needs

Strong efforts are being made by Neotropical countries to implement their obligations under the Ramsar Convention. However, lack of funding for environmental matters and a general lack of political decision, are making progress slow in most cases. In spite of this, both governmental institutions and NGOs are achieving important results: many countries in the Neotropical Region are developing National Wetland Policies or Strategies in an effort to improve the existing legislation, and Environmental Impact Assessments are already incorporated in the legislation of several countries. A number of National Wetland Committees have been organized to guarantee the participation of all sectors of society (governmental, NGOs and private) on wetland issues and most countries in South and Central America (14 out of 19) have already become Contracting Parties to the Ramsar Convention, a clear sign that the will to change things exists. However, with only 1 Contracting Party out of 13 Caribbean countries, strenuous efforts will be made in the next few years to recruit new members in this part of the region.

Much effort is being directed towards training and capacity building, with local and foreign funding. Many universities, institutes and technical schools are providing degree programmes as well as workshops on wildlife and natural resource management and some have started specific curricula on wetland conservation and wise use.

Management plans are being prepared and implemented at a slow but steady rate. Basic research is badly needed, especially applied research on topics such as harvesting of wildlife and forestry resources. Implementation of management plans is probably the most critical problem when the good will and interest exist but not the economic capacity to carry them out. Some countries, however, have found an alternative solution with governments arranging for NGOs and/or local associations to be responsible for the management of protected wetland sites.

The Future for Neotropical Wetlands

Much remains to be done in wetland conservation and wise use in the Neotropical Region. For this, the highest levels of political and economic decision making must be reached. Environmental agencies within governments, NGOs, universities, as well as indigenous people and local communities are playing an ever increasing role in making this change possible. This is a continent where there is still time to secure natural resources for the benefit of future generations as long as there is a commitment to learn from each others failures and successes.

Case Study 1: Argentina/Bolivia/Chile/Peru 

Wetlands of La Puna

By Sandra Caziani, Universidad Nacional de Salta, Argentina

Main Features of La Puna

At an altitude of 3,500 - 4,000m, La Puna or the High Andean Plateau of the Central Andes, is shared by Argentina, Bolivia, Chile and Peru. It is a cold, desert region with intense solar radiation and strong winds which cause extreme temperature variations. There is a dry winter season and average annual temperature and rainfall do not exceed 10°C and 500mm per year respectively.

Three large units can be distinguished altitudinally in La Puna: prepuna, Puna in the strict sense and the high Andean region. The prepuna is dominated by small sparse woods of the column-like cactus 'Cardón' Trichocereus sp. and the leguminous tree 'Churqui' Prosopis ferox. La Puna is characterized by scrub steppes of grasses and hard-leaf 'Tola' Parastrephia sp. and scattered Polylepis sp.'Queñoa' forests. In contrast, the high Andean region has largely exposed rocky soils with grasses and cushion plants which are adapted to the dry conditions here.

Many of the rivers flowing to tropical and subtropical forest regions have their sources in these areas, but others form endorreic watersheds (i.e., with no exit to the sea) ending in lakes and 'salares' or salt basins of different sizes. The water volume of rivers and associated lakes varies according to season, with rains and snow melt occurring between October and March (summer). Some lakes are shallow, containing saline and hypersaline water with plankton made up mostly of diatoms. Other deeper and only slightly saline wetlands have abundant submerged vegetation and zooplankton rich in small crustaceans. During the dry season, the natural shrinkage of these wetlands exposes a cover of macrophytes and algae called 'colcha' on which domestic animals feed.

High altitude peatlands or 'bofedales' are found in some areas. Flooded by surface water or by the upwelling of underground fresh water, their vegetation is compact and cushion-like, with grasses, rushes and sedges which remain green almost all year. Behaving rather like gigantic sponges which slowly set water free in the dry season, these areas are very important sources of food for wild and domestic herbivores and they also serve as water reservoirs.

James's Flamingo, an endemic species, feeding at Vilama Lake. (Photo: Sandra Caziani)

Fauna Associated with the Wetlands

The threatened Vicuña Vicugna vicugna (IUCN Red List, 1994) and the Puna Rhea Pterocnemia pennata, which is seen in family groups, graze on the steppes and 'bofedales'. It is also common to observe Andean Condor Vultur gryphus feeding on dead llamas. Yet in the middle of this desert landscape, the greatest explosion of life is without a doubt associated with the lakes and 'salares'; the great variety and number of birds, many of them endemic to La Puna, is particularly striking. On the saline lakes, thousands of the endemic James' and Andean Flamingos Phoenicopterusjamesi [note: many authorities record this genus as Pheonicoparrus] and P. andinus can be seen in the water, filtering micro-organisms with their specially adapted bills. They nest in colonies and lay a single egg in nests of mud and gravel. It is common to find large concentrations of Wilson's Phalarope Steganopus tricolor feeding near the flamingos. Hundreds of thousands of individuals of this small species migrate every year to the northern regions of North America where they breed. Chilean Flamingo Phoenicopterus chilensis is also found in these wetlands, usually together with Horned and Giant Coot Fulica cornuta and F. gigantea which feed on the same species of plants they use for building their nests. The latter species is very local and can be found in significant numbers in some of these wetlands, such as Laguna Pululos (Argentina), Lago Me–ique and Lago Miscanti (Chile), Laguna Colorada and Laguna Pelada (Bolivia). Lakes with submerged vegetation support large numbers of waterfowl including Puna Teal Anas puna, Crested Duck, Anas specularoides, Ferruginous Ruddy Duck Oxyura jamaicensis ferruginea and Andean Goose Chloephaga melanoptera.

Use and Conservation of the Wetlands

A cultural richness derived from a combination of indian and hispanic elements is typical of this region, as are the houses built of 'adobe'. During the Inca period, human population here was high compared with the sparsely distributed population of today. Extensive farming (camelids and sheep) and mining are now the main activities and although potatoes, corn, and other crops are grown in some areas, it is on a much smaller scale than in prehispanic times; the terraces and irrigation systems used in the past can still be found and in some cases efforts are being made to restore them.

The Spanish invasion dramatically changed the social and trade systems, transforming sedentary farmers into semi-nomadic shepherds and introducing domestic sheep and goats to the llama ranches. Shepherds build 'pircas' (a rock enclosure forming a paddock or corral where pastures are managed) around 'bofedales', to manage the use of these rich pastures by livestock, and these paddocks can be seen scattered throughout the landscape.

At present, animal grazing is associated with the wetland cycle as animals are moved to higher or lower areas to take advantage of the seasonal changes in vegetation growth. For example, the 'colchas' might be used during the winter while the 'bofedales' in higher areas are used in the summer. Unfortunately, little is being done to promote sustainable farming among the inhabitants of the Puna, and overgrazing is contributing to excessive erosion in some areas, especially around wetlands.

Trees and bushes in La Puna continue to be used for fuel in homes and mines, and as material for building enclosures and houses. The light and beautiful wood of the 'cardones' is ideal for furniture and handicrafts. However, the growth of these woody plants is very slow and the loss of vegetation cover due to both cutting and overgrazing increases the erosion of the poorly developed, fragile soil which prevails here.

Severe droughts lasting several years are frequent and cause the disappearance of some of the wetlands and the shrinkage of others. In addition to this natural process, wetlands are facing other threats: siltation, drainage and pollution of the water. Siltation is the result of the accumulation of sediments carried by the water as part of natural processes and the loss of soil due to human activities (e.g. loss of vegetation cover through firewood collection and overgrazing). Mining and salt extraction (sulphates, borates and others) may contribute to wetland pollution or the loss of wetlands as large amounts of water are used to process the minerals.

Plants and animals are extremely well adapted to the harsh weather conditions found here, and therefore any modification of the ecological characteristics of their fragile environment will mean an almost certain threat to their survival. Most of these negative processes could also adversely affect the rainfall cycle and perhaps reduce the agricultural productivity of the area.

Important wetlands have been or are being designated as Ramsar sites: the Laguna Colorada (Bolivia); the Salar de Surire National Nature Monument and the Lauca National Park (Chile); and the Laguna de Pozuelos National Nature Monument (Ramsar Site and Biosphere Reserve) and Lagunas Vilama and Pululos (Argentina). This is a very important step towards the protection of these rich wetlands since their conservation in the long term depends on the wise use of resources in the basins, including the development of both sustainable farming techniques and alternative means of production for the population in the area.

Case Study 2: Argentina/Chile

Tierra del Fuego

By Roberto P. Schlatter, Universidad Austral de Chile, Chile

Early History

Located on the southern tip of South America, Tierra del Fuego extends over 35,000km2 including Isla Grande as well as islands and archipelagos to the south of the Strait of Magellan. The innumerable intermittent columns of smoke and fire which early explorers sighted along the coast gave the area its name, Tierra del Fuego, Land of Fire. The first signs of human life in the region go back to approximately 10,000 B.C. Several indigenous peoples, shared this remote corner of the world:

-- the Haush, who were the most numerous;

-- the Onas (Shelknam), who were the most aggressive and dominant - they were the great hunters of Guanaco Lama guanicoe on the steppes of Isla Grande;

-- the Yahganes or Yamanas, who inhabited the far south, living most of the time in canoes;

-- the Alacalufes (Kawaskar) from the northwestern archipelagic region in an area which is now Chilean territory.

Major Features

The island is marine in origin from the Tertiary period with a postglacial topography. The layer of volcanic ash and organic soils covering the bedrock measures only 30cm in depth at maximum, resulting in fragile soil conditions. The northern part of the Isla Grande is cold and dry (less than 200mm rainfall annually) and is typically temperate South American grassland with the dominant grasses Festuca gracillina and Chiliotrichium diffusum. A chain of mountains with deciduous Lenga Nothofagus pumilo forests is located to the west and south. Moving further west and south again, there is a rainy zone with perennial subantarctic rain forests where the dominant tree species are Magellan 'Coigue' Nothofagus betuloides, along with 'Canelo' Drimys winteri and Magellan 'Maitén' Maytenus magellanica which are less abundant. In the highlands 'Ñirre' Nothofagus antarctica is the dominant species. With rainfall exceeding 7,000 mm per year on occasions, these sometimes form stunted forests.

The Diversity of the Wetlands

Tierra del Fuego has varied and abundant wetlands. The largest catchment area on the island is that of the Río Grande which covers 8,821km2. Its sources of water are Lago Deseado through Río Turba, and Lago Blanco through Río Grande. Inland wetlands include lakes, lagoons and peatlands, and the most important concentration of wetlands is located between San Sebastián (Argentina) and Inœtil (Chile) bays in the northern part of Isla Grande. The largest lake, Lake Fagano or Cami, however, is found towards the southern part of Isla Grande.

Along the coast and in the marine sectors, there are large sandy and stony beaches, numerous fjords, inlets and bays with wetlands which are highly variable in terms of salinity, and with luxuriant algae and peatlands surrounding them. Islands and fjords particularly in the exposed sector possess a large concentration and diversity of marine bird species.

Sphagnum peatlands, dominated by Sphagnum magellanicum, are the most extensive wetlands. Peatlands cover approximately one third of the deciduous and perennial forest area and they are essential in maintaining and regulating the drainage of groundwater which originates from rain and melting ice. This is a wetland type of great importance because of its fragility. It is also of importance to local people as it is used as a source of fuel.

A typical landscape in the transitional zone between rain and deciduous forest near Seno Almirantazgo, at 300m above sea level in the Rio Cóndor watershed, Tierra del Fuego. In the foreground is Sphagnum peatland and Nirre forest with some Coigue and Lenga trees. (Photo: R. P. Schlatter).

The richest wetlands in terms of both biomass and number of species (particularly invertebrates and algae) are the coastal wetlands, especially bays and estuaries which abound with bird species such as the Flightless Steamer Duck Tachyeres pteneres which feeds on molluscs along the shore; the Kelp Goose Chloephaga hybrida which feeds on the extensive Kelp beds; the Southern Giant Petrel Macronectes giganteus which lives at sea but comes ashore to feed on dead whales and other carrion. The Magellanic Penguin Spheniscus magellanicus nests on the islands of the Strait of Magellan and the Beagle Channel, although none nest on Isla Grande, and it can be regularly seen along the coasts of Tierra del Fuego. The marine otter Lutra felina, which once lived in the fjords, and the Southern River Otter Lutra provocax, which was found in the rivers of Tierra del Fuego, almost became extinct in the past because of hunting pressure but both species seem to be showing signs of recovery. The Guanaco is still abundant on Isla Grande.

Plant life on the island and archipelagos, numbering some 370 species, is not especially rich in terms of numbers. However, the species involved, their distribution and adaptations to the particularly difficult climatic, hydrological and soil conditions, make this plant life unique.

Threats to the Integrity of Tierra del Fuego

A number of activities within the area pose threats to the wetlands:

-- In the past, fire has been a major problem in Tierra del Fuego together with the conversion of land for grazing. These activities contributed to the extermination of the Onas, Yahganes and Haush Indians and decimated animal species such as the Guanaco.

-- Overstocking, trampling, grazing and wind erosion as a result of sheep and cattle farming have been harmful. Around 50% of the natural prairies are in poor condition as a result of this.

-- Oil drilling in the northeast has an impact, with pollution from oil spills affecting many parts of the Strait of Magellan.

-- Crab harvesting is not only exterminating the resource, but also affecting penguins and dolphins that are caught for use as live crab bait.

-- The introduction of non-native fish species such as Brown Trout Salmo trutta and the salmon Onchorynchus mykiss, and mammals such as the North American Beaver Castor canadensis and Muskrat Ondatra zibethicus are a major threat to the few native species adapted to low levels of organic matter in the wetlands.

-- Forestry is beginning to have an effect on river banks, lake shores, peatlands and basins, in the absence of correct environmental planning. Until now, there has been no forest management strategy and in this environment of fragile soils this presents a real threat to ecosystem stability.

Protection of Tierra del Fuego's Biodiversity

On the Chilean side of the Tierra del Fuego much of the animal life and environment are now protected within two of the largest national parks in the country, Cabo de Hornos and Alberto de Agostini, and two Monument Parks, Cisnes Lake and Los Pinguinos while on the Argentinean side the area is protected within the Tierra del Fuego National Park. Argentina has the only Ramsar site in Tierra del Fuego so far, the Reserva Costa Atlántica de Tierra del Fuego which includes Bahía San Sebastián, an important area for shorebirds.

Further Reading

• Findlicher, E.L. y Santana, A. 1988. El Clima del sur de la Patagonia y sus Aspectos Ecológicos. Un Siglo de Mediciones Climatológicas en Punta Arenas. Ans. Inst. Pat. Ser. Cs. Nats. Punta Arenas (Chile) 18:57-86.
• Heusser, C.J., Heusser, L.E. y Hauser, A. 1990. A 12,000 Yr B.P Tephra Layer at Bahia Inútil (Tierra del Fuego, Chile). Ans. Inst. Pat. Ser. Cs. Nats. Punta Arenas (Chile) 19: 39-49.
• Pisano, E. 1983. The Magellanic Tundra Complex. In: A.J.P. Gore (ed), Mires, Swamp, Bog, Fen and Moor. Ecosystems of the World 4B, Regional Studies. Elsevier Scientific Publishing Company. Amsterdam.
• Pisano, E. 1992. Sectorización Fitogeográfica del Archipiélago Sud Patagónico Fueguino. V: Sintaxonomia y distribución de las unidades de vegetación vascular. Ans. Inst. Pat. Ser. Cs. Nats. Punta Arenas (Chile) 21:5-34.

Case Study 3: Belize

Belize Barrier Reef

By Sue Wells, UNDP/GEF Coastal Zone Management Project, Belize

"The Most Remarkable Reef in the West Indies"

So Charles Darwin referred to the Belize Barrier Reef in 1842, in his study of the origin and evolution of coral reefs. Since then it has become renowned as the largest barrier reef in the Western Hemisphere. Nearly 260km long, it runs from the northern border of the country, where it is only about 1km offshore, south to the Sapodilla Cayes which lie some 40km offshore.

Belize also has one of the most diverse reef ecosystems in the world, with all the main types of reef represented: fringing reefs along the mainland coast; the Barrier Reef itself which grows along the edge of the continental shelf, separated from the mainland by the lagoon; and three offshore atolls (Lighthouse Reef, Turneffe Atoll and Glovers Reef). The presence of atolls is unusual. Most atolls are found in the Pacific, where they form on the top of submerged volcanoes. Very few occur in the Caribbean, and they differ in structure, the three in Belize for example lying on non-volcanic submarine ridges.

The Diversity of Coral Reefs

Of all wetlands, coral reefs are the most diverse, being home to more species than any other marine ecosystem. Only tropical rain forests rank higher on the biodiversity scale. This huge diversity is a result of careful partitioning of the reef by all its inhabitants - some use the reef at different times of day (many reef species are nocturnal), others share it by eating different food. Although reef diversity is much lower in the Caribbean than in the Indo-Pacific (a result of the geological history of the region), over 1,000 species may nevertheless occur on a single reef. Belize has a particularly high species diversity for the region, with about 65 coral species and over 300 fish species, compared with just over 70 coral species and about 520 fish species in the Caribbean as a whole.

The colourful Queen Angel, one of the 300 fish species recorded at the reef. (Photo: James Beveridge)

Fish and invertebrates (notably molluscs, crustaceans, echinoderms and corals) predominate, but algae are also abundant. More species of fish are found on reefs than anywhere else in the sea, ranging from large sharks to tiny gobies. Most species on a reef are in fact never seen by divers and snorkellers as they are tiny, cryptic invertebrates that live in cracks and crevices and can be equated with the insects of the tropical rain forest. It is also likely that about 90% of all reef species, particularly the small invertebrates, are still undiscovered: SCUBA diving equipment was invented less than 50 years ago, and most reefs have only relatively recently become accessible to researchers. New species are being described all the time. For example, an entirely new biodiversity 'hotspot' has been discovered on the Belize Barrier Reef in the last two years in the semi-enclosed lagoons of the Pelican Cayes, a group of mangrove covered cayes. These have startlingly rich, colourful and unusual communities of sponges, corals, and other reef species encrusting the mangrove roots and lagoon sides; in one lagoon, over 40 species of seaquirts (a small, primitive, chordate) have been found.

Reefs also attract large animals such as turtles including the threatened Hawksbill Turtle, Eretmochelys imbricata (IUCN Red List, 1994), and seabirds such as the Red-footed Booby Sula sula and the Magnificent Frigatebird Fregata magnificens, which come to feed on the smaller inhabitants or which depend on the closely associated seagrass beds and mangrove habitats. Although all three wetland types can and do occur independently of each other, in many areas they form an integrated ecological system. Mangroves thrive in calm, turbid, nutrient rich environments, protect reefs from terrestrial sediments and provide shelter among their roots for many juvenile reef species. The seagrass beds stabilize sediments and also provide an important food source for many reef animals. Coral reefs require clear nutrient poor waters, and play an important role in protecting mangroves and seagrasses from erosion during storms and strong wave action. The Belize reef ecosystem illustrates this well, the reef protecting and being linked with extensive areas of coastal wetlands, lagoons, seagrass beds and mangrove-covered cayes and coastal areas.

Utilization of the Reef

In Belize, the coastal waters were used extensively for fishing by the Mayans between 300 B.C. and 900 A.D. Since early this century, the economic role of the reef has increased steadily with the growth of the coastal population. Initially, its importance lay in the fishing industry, with a wide variety of species being harvested ranging from turtles, sharks and finfish, to sponges and seaweeds. Today, lobster and conch are the principal fisheries products, and contribute most of the total value of exported seafood, estimated at over US$10 million in 1995. There is also a domestic fishery for shallow reef fish and a commercial fishery for groupers Epinephelus spp. and snappers Lutjanus spp. However, the main use of the Belize Barrier Reef is now tourism, which is the country's largest source of foreign exchange generating an estimated US$75 million in 1994; hundreds of divers visit the reef each year to experience its delights.

Threats to the Reef System

Belize may be one of the last countries in the world to have extensive areas of almost pristine reef but it is also subject to the many threats that are of global concern and which have already seriously degraded an estimated 10% of the earth's coral reefs and currently threaten a much greater percentage. Greatest damage comes from sedimentation, agrochemical run-off, coastal development, tourism and overfishing. Until recently, the main impacts on the Belize Barrier Reef were from natural events such as hurricanes. However, pressures are mounting from a whole range of impacts including escalating residential and hotel development on numerous cayes, the citrus and banana industries which are causing increasing fertilizer run-off, growing numbers of shipping and recreational vessels in the reef-strewn shallow waters, and a steady increase in divers and snorkellers - Hol Chan Marine Reserve alone now receives over 30,000 visitors a year.

Status of Belize Coral Reef

Coral reefs have not yet been used among the primary criteria for listing wetland sites under the Ramsar Convention, although the definition of a wetland allows for their inclusion. Of the 11 Contracting Parties to Ramsar in the Neotropics that have coral reefs, only 3 have listed sites that include these habitats (the Grand Cul de Sac Marin in Guadeloupe, Klein Bonaire Island and adjacent waters in the Netherlands Antilles, and North, Middle and East Caicos Islands in the Turks and Caicos) and in all cases the main interest in these wetlands has been other habitats and waterfowl. Belize is finalising the process for joining Ramsar and, in the first instance, will be nominating an inland wetland site. However, several parts of the Belize Barrier Reef would qualify for nomination.

A system of marine and coastal protected areas is being set up as part of the Coastal Zone Management Plan that is being prepared for the country. So far there are three protected areas that include reefs: Half Moon Caye Natural Monument on Lighthouse Reef, Hol Chan Marine Reserve on the Barrier Reef, and Glovers Reef Marine Reserve. A number of other areas are likely to be designated as marine reserves or national parks soon, and many of these will be large areas incorporating a range of wetland habitats including the central section of the Barrier Reef, extensive lagoon and saltmarsh areas as well as vast expanses of estuaries, mangroves and fringing reefs.

Case Study 4: Colombia

Forest Wetlands of the Colombian Southern Amazon

By Luis Germán Naranjo, Universidad del Valle, Colombia

Pristine Wetlands

In Colombia, the region called Amazonia comprises nearly one fourth of the national territory. However, its inaccessibility prevented intense colonization until very recently and therefore vast areas still can be considered as pristine. The original habitat included a complex mosaic of vegetation types, whose spatial distribution was largely determined by minor variations in topography and soils. Nonetheless, the dominant habitats in the Colombian Amazon (as well as throughout most of the Amazon Basin) can be described as a vast complex of wetlands. The periodic floods of the Amazon River and its complex network of tributaries determine the existence of a wide array of wetland habitats with a marked seasonal pattern of variation both in the composition of their biotic communities, and in their ecological attributes and functions.

The region around the southern tip of the Colombian Amazon, and the southernmost part of Colombia, is included within the Amacayacu National Park, an area covering 175,000ha. Mean temperature in the area is 260C and annual precipitation near to 2,900mm. The rainfall pattern determines the seasonal pattern with high waters occurring during the first months of the year followed by a period of low waters around June and July. After the 'dry' season, minor fluctuations or 'repiques' occur throughout the area, when the levels of the rivers rise and descend irregularly.

Biodiversity of the Wetlands

Although there is local variation in the composition of plant communities, a generalized succession from wetlands to inland forest for the Colombian Amazon comprises four major stages. In the first place, in the oxbow lakes and swamps, an array of floating plants dominated by the spectacular Regalia Lily Victoria amazonica, the largest pond lily in the world, is replaced at the edges by emergent grasses and weeds. At the shoreline the forest begins, dominated by two tree species whose seeds are dispersed by the water. The third vegetation type occurs in small, permanently flooded depressions. It consists of almost pure stands of the palm Mauritia flexuosa whose local name 'cananguche' is the source of the term 'cananguchal' applied to this peculiar kind of wetland. Finally, the 'cananguchal' is surrounded by mixed stands of trees of small size, which are exposed to irregular floods when the water level of the rivers becomes exceptionally high.

With such a complexity, the Colombian Amazon wetlands support a highly diverse fauna, varying in composition with the extension and contraction of the flooded areas, and with the structure of the vegetation which fluctuates in response to the hydrologic and climatic regimes. The Colombian Amazon supports about 1,700 species of vertebrates of which the most diverse are freshwater fishes and forest birds, each with about 600 species recorded to date. There are several charismatic mammals dependent on the rivers and adjacent habitats such as the Amazon River Dolphin Inia geoffrensis, the Tucuxi Sotalia fluviatilis, the Amazonian Manatee Trichechus inunguis, and the Great Otter Pteronura brasiliensis, all of which are threatened species (IUCN Red List, 1994) and, of course, the Jaguar Panthera onca.

Traditional and Future Use of Wetland Resources

It is therefore not surprising that much of this area around the southern tip of the Colombian Amazon is the homeland for about 11 indian tribes which have a long tradition of cultural use dependent on the wetland system. Fortunately, most of their traditions were developed on the basis of a reasonable understanding of the attributes, functions, and values of the wetlands, and therefore the impact of these cultures on the resources of these ecosystem can be considered as almost negligible.

However, the pressure from a growing population of settlers from different regions might represent a potential threat for wetlands and other ecosystems of the Colombian Amazon. Near the Amacayacu National Park, the city of Leticia, capital of the Departamento del Amazonas, remained as a slowly growing settlement for many years after its foundation in 1964. Today, it is one of the most important townships of the entire Colombian Amazon and, despite the relatively small size of its human population (21,868 inhabitants according to the 1993 census), it harbours about 60% of the total population of the Department and has a steady, high rate of annual population increase averaging 3.7%. Although much of the population depends on resources imported from other regions of Colombia and neighbouring Peru and Brazil, the increasing growth of the city still imposes a heavy toll on natural resources from surrounding areas. In addition, Leticia attracts a significant number of tourists every year, whose activities and impacts should be added to the compounded effect of the development projects throughout the area.

During the last few years, there has been a growing interest within the Colombian government in the Ramsar Convention. If this intention ends in positive results, the list of potential Ramsar sites in the country should include a sample of the extremely diverse Amazonian wetlands. From a local, and a regional point of view, they are unique and have a high value for native cultures besides their importance for the continued existence of several endangered taxa. As a bonus, a more integrated approach to land management practices throughout the region could be implemented and the future development of this small part of the country located in the southern hemisphere could then take place on a sustainable basis.

Further Reading

Departamento Administrativo Nacional de Estadística. 1994. XIX Censo Nacional de Población y de Vivienda: Amazonas. Resumen Ejecutivo. Santafé de Bogotá, Colombia.

Instituto Nacional de los Recursos Naturales Renovables y del Ambiente. 1984. Financiera Eléctrica Nacional. Parques Nacionales, Colombia.

Proyecto Radargramátrico del Amazonas. 1979. La Amazonía Colombiana y Sus Recursos.Talleres Gráficos Italgraf, S. A. Bogotá Colombia.

 Case Study 5: Costa Rica

The Seasonal, Freshwater Marsh at Palo Verde National Park

By Michael B. McCoy, Regional Wildlife Management Program,
National University, Costa Rica

Introduction

Recent efforts in the 1980s to preserve two protected tropical wetland ecosystems on opposite sides of the globe, both internationally renowned for their importance to migrating and resident waterfowl, failed to continue to provide the necessary habitat to waterfowl for one simple reason: the forced cessation of cattle grazing of each marsh. In both cases, in a sincere effort to protect a valuable ecosystem, just the opposite effect was achieved. One of these marshes is in Keoladeo National Park, south of New Delhi, India (see Ali and Vijayan 1986 for a review). The second of these marshes was Palo Verde in Costa Rica, Central America, where the elimination of grazing gave way to a massive invasion of the cattail Typha dominguensis with a corresponding drastic decrease in use by waterfowl.

Palo Verde and its Bird Life

The Palo Verde marsh is a 'back marsh' about 5km long and 1km wide running parallel to the Tempisque River and about 20km upstream from this river's mouth at the Gulf of Nicoya, northwestern Guanacaste Province. Strong tidal fluctuations stir up riverbed sediment which is deposited along the bank during dry season high tides. The marsh, isolated from the river by this natural levee, fills to shallow depths of up to 1.25m with rainwater during the wet season. The marsh commences drying in December, and by April is completely dry.

For decades, the marsh was probably the most important wetland area in Central America for about 60 species of resident and migratory waterbirds. In 1979, during a single count in the dry season, it was common to observe up to 35,000 Black-bellied Whistling Ducks Dendrocygna autumnalis, 25,000 migratory Blue-winged Teal Anas discors and large numbers of other species of migrating ducks such as: Northern Shoveler Anas clypeata; American Wigeon Anas americana; Ring-necked Duck Aythya collaris; and Lesser Scaup Aythya affinis. In addition to these migrating birds, up to 500 Muscovy Duck Cairina moschata, and several hundreds of wading birds such as Wood Stork Mycteria americana, Roseate Spoonbill Ajaia ajaja, Great Blue Heron Ardea herodias, and up to three or four pairs of Jabiru Stork Jabiru mycteria (only 40 individuals remain in Costa Rica), were observed in this marsh in the dry season. In short, the marsh was a paradise of bird and plant diversity. Precisely because of this, the board of directors of the Agrarian Development Institute, after expropriating the cattle ranch within the area, donated the marsh and surrounding forest to the Costa Rican National Parks and Wildlife Service in 1977. This became the first National Wildlife Refuge in Latin America (4,000ha).

Cattle and the Maintenance of Diversity

Traditionally, since at least 1923, the marsh and natural levee (1,000ha) were heavily grazed from November (end of wet season) until March or April by anywhere from 10,000 to 15,000 head of cattle. As the upland areas of this huge ranch dried out and water became scarce, the cattle were brought down to the marsh. This incredibly heavy grazing force (15 cows per hectare) over a period of decades left a very open marsh, with virtually no tall emergent vegetation, but with a diverse flora of about 60 species. During the wet season, large expanses of deeper water were covered by floating vegetation (Nymphea sp.) only. The undulating marsh floor created shallower areas where low-growing sedges Eleocharis mutata and small Palo Verde trees Parkinsonia aculeata thrived under shorter hydroperiods.

In December, with the onset of strong northeasterly trade winds and the entrance of cattle into the marsh, the floating vegetation was broken up and pushed towards the shallower areas of sedges, thereby creating open water in the deeper pools and channels. As water levels dropped, bands of exposed soil formed between the open water and the shallower sedgebeds. The combination of shallow, open water near to exposed soil was the attractant for the varied bird life that descended upon the marsh at that time.

A Management Problem

In 1980 when Palo Verde became a national park (a category in Costa Rica which does not allow human use), one of the first acts of the new administration of this area was the elimination of cattle from the marsh. From that moment on a rapid transformation of the marsh vegetation was observed. The small patches of cattail that existed in 1980 (covering 40-50ha) were able to capitalize and fill in the void covering 95% of the 500ha marsh by 1988 and preventing the development of the very important interface of 'shallow, open water-exposed soil-sedgebeds' during the dry season; thus the dramatic decrease in waterbird usage in the 1980's, during the dry season concentration. In February of 1988 peaks of only 3,000 Black-bellied Whistling Ducks and 500 Blue-winged Teal were counted and almost no wading birds arrived at all to the marsh.

To make matters worse, the lack of grazing in upland areas created dangerous levels of a tall, fire-loving, non-native species, African Blue-stem Grass Hyparrhema rufa. The resulting forest fires entered the marsh during several dry seasons. The flames from the dried cattail leaves wiped out virtually all Palo Verde trees (only nesting sites for six pairs of Everglades Kites Rostrhamus sociabilis in 1979) and essentially fertilized new cattail growth upon arrival of the wet season. Almost no other vegetation co-existed in the dense cattail stands that resulted, and much dry forest was also lost in the process.

In other words, the ecosystem's biodiversity was maintained by severe overgrazing, a rather odd consequence. Removal of the grazing effect eliminated the plant and animal biodiversity of the marsh and produced the largest cattail marsh in the region.

Restoration of Palo Verde

In 1987 research began into the restoration of this marsh to conditions similar to that of 1979. After opening up 30ha with underwater mowing to eliminate cattail and underwater cuts at soil level in shallow and deeper water, that all-important interface of 'open, shallow water-exposed soil-low sedges' formed along the margins in the deeply cut area for the first time in a decade. The response was nothing short of incredible:

• most of the original 60 species of plants came back on their own in treated areas;
• Black-bellied Whistling Ducks peaked at 17,000 and Blue-winged Teal at 4,000 (1990);
• Whistling Ducks, White Ibis Eudocimus albus and Glossy Ibis Plegadis falcinellus utilized the floating vegetation;
• one pair of nesting Jabiru Storks fed exclusively in this habitat;
• Wood Storks and Roseate Spoonbills utilized the open water area for feeding.

In 1991 complete cattail control was achieved by crushing the cattail stems in the water with a farm tractor. Whistling Duck numbers in 1991 were close to 20,000, and Blue-winged Teal increased even more to 13,000.

Cattle grazing the marsh at Palo Verde and creating waterfowl habitat. (Photo: Michael McCoy)

While cattail is now under control, an increase of a tall water grass Paspalidium sp. occurred in the mid-depth and shallow water areas after the elimination of cattail which can mask the 'shallow water-exposed soil-sedgebed' interface. Preliminary tests with 30 head of cattle in 30ha has shown potential to control this grass and at the same time provide forage for grazing. The Ramsar Wetland Conservation Fund helped finance the fencing of two 25ha experimental plots in 1994 to test the effect of different grazing intensities on marsh vegetation and waterfowl.

The new Management Plan for the park recognizes the important role of cattle grazing, at least in the dry season. In addition to maintaining a preferred habitat for waterfowl, an economic gain can be made through modest grazing fees, and more importantly, an economic gain can be made by neighbouring, small-scale ranchers. Such a benefit is important from the standpoint of a better identification of the park with the local communities, who in the end will determine the destiny of this area. Effort is underway to organize these ranchers not only to graze the marsh in the dry season but also to graze the upland pasture areas during the wet season, to protect the dry forest, and thus return to the traditional grazing system that produced one of the most remarkable habitats in Central America.

Further Reading

Ali, S. and Vijayan, V.S. 1986. Keoladeo National Park Ecology Study. Summary report 1980-85. Bombay Natural History Society. Bombay, India.

McCoy, M.J. and Rodríguez, J.M. 1994. Cattail (Typha dominguensis) Erradication Methods in the Restoration of a Tropical, Seasonal, Freshwater Marsh. In W. J. Mitsch (eds) Global Wetlands: Old World and New. Elsevier Science B.V., Amsterdam, Netherlands.

Sánchez, J., Rodríguez, J.M. y Salas, C. 1985. Distribución, Ciclos Reproductivos y Aspectos Ecolgicos de Aves Acuáticas. In E. Guier (ed), Investigaciones Sobre Fauna Silvestre de Costa Rica. Editorial de la Universidad Estatal de Distancia, San José, Costa Rica.

CHAPTER 7

THE NORTH AMERICAN REGION

An Overview of North American Wetlands

By Kenneth W. Cox. North American Wetlands Conservation Council (Canada), and Gilberto Cintrón, U.S. Fish and Wildlife Service, United States of America

Extent of North American Wetlands

North America is the third largest continent, covering over 24 million square kilometres; geographically extending from the Arctic Ocean to the warm tropics, the region spans more than 60° of latitude. Canada and the United States occupy much of north central North America, while Mexico extends to its southernmost limit. All three countries are Contracting Parties to the Ramsar Convention.

The North American continent contains a large percentage of all the world's wetlands. These range in size from small, seasonal wetlands (less than a hectare) to vast wetlands spanning immense portions of the landscape. Canada holds about 24% of the world's wetlands, encompassing over 127 million hectares. This is approximately 14% of the entire landscape and about three times the wetland area found in the United States, excluding Alaska.

Wetlands covered 89 million hectares in the United States (excluding Alaska) at the time of the nation's settlement. Today, only 43 million hectares (47%) of the original wetland area remain. In stark contrast, an estimated 81 million hectares of Alaskan wetlands remain mostly undisturbed. In Mexico, wetlands occupy over 2 million hectares, almost two-thirds of these occur on tropical coastlines.

The region has 54 Ramsar sites (Canada 33, United States of America 15 and Mexico 6), amounting to only 7% of Ramsar sites world-wide. However, collectively they cover over 15 million hectares accounting for almost 28% of the total area of Ramsar wetlands, a reflection of the vast size of some of the North American sites.

Wetland Diversity

The large diversity in wetland types reflects the latitudinal span of the North American land mass (from the Arctic to the tropics) and the different climatic conditions, hydrologic regimes, and numerous landscape types found within it.

Extensive Arctic wetlands are found in northern and western Alaska. Most notable are the moist tundra wetlands of the North Slope Coastal Plain, used by Barren Ground Caribou Rangifer arcticus for calving and feeding. In Canada, the Arctic wetlands include the sedge meadows of the Athabasca Delta which provide grazing for the world's largest ranging herd of Bison Bison bison, and a rich diversity of other mammals such as Grey Wolf Canis lupus and Lynx Lynx canadensis. In spring and autumn the delta supports over a million birds including many species of ducks, geese and the threatened Whooping Crane Grus americana (IUCN Red List, 1994). Other extensive wetlands include the Mackenzie and Yukon river deltas as well as the massive Hudson and James Bay lowlands in the eastern central portion of Canada.

Vast portions of the boreal life zone of North America are dominated by peatlands (bogs and fens). Some 110-130 million hectares of peatlands are found in Canada alone, giving this country the largest peat resources in the world. The bogs and fens of the Boreal region provide seasonal habitat for large mammals, including Woodland Caribou Rangifer caribou and Moose Alces americana, and many other mammals such as Beaver Castor canadensis and Muskrat Ondatra zibethicus. The largest concentration of Canadian wetlands are boreal forested peatlands found in the provinces of Manitoba and Ontario, where it is estimated that 22.5 million hectares and 29.2 million hectares of wetlands, respectively, remain.

The wetlands of the Great Lakes and the St. Lawrence Basin consist of bogs, fens, marshes, and forested swamps that are important habitats for migratory waterfowl. The Great Lakes coastal marshes are connected to the largest reservoir of fresh water on earth (the five lakes have a coastline which exceeds 15,100km and cover an area of 246,568km2). Several wetlands along the Great Lakes in southern Ontario are designated as Ramsar sites. These wetlands provide spawning ground for important freshwater fish species such as Muskellunge Esox masquinongy, Largemouth Bass Micropertus salmoides, Yellow Perch Perca flavescens, and Pumpkinseed Lepomus gibbosus. Six species of turtle and several amphibian species are dependent on these habitats. Many thousands of migratory birds, including several duck species, and the Canada Goose Branta canadensis use these areas for breeding. Aside from their rich animal and plant diversity, the wetlands also provide many natural products to one of the most populated regions in Canada.

The Canadian provinces of Manitoba, Saskatchewan and Alberta, and the American states of Minnesota, and North and South Dakota, encompass a vast area (780,000km2) where numerous freshwater marshes occupy depressions formed by Pleistocene glaciers. This Prairie Potholes region is the single most important breeding habitat for most North American ducks: approximately 60% of the continent's ducks are raised here, as well as an unknown, but large, proportion of other prairie-dwelling marsh and aquatic birds. The Prairie Potholes region is also a major world producer of cereal grains presenting great challenges to the conservation of these wetlands.

Extensive areas of coastal and estuarine wetlands occur in the North American Region stretching from Atlantic Canada, throughout the entire length of Atlantic U.S. and into coastal lagoons of Mexico's east coast. While not as abundant, Pacific shorelines contain coastal lagoons and river delta wetlands. On Canada's east coast the high tidal amplitudes (to 13m) of the Bay of Fundy have created extensive areas of tidal saltmarsh and intertidal flats that are critically important to international populations of shorebirds. More than 80% of the world population (over 3 million birds) of the Semi-palmated Sandpiper Calidris pusilla forage on the tidal mudflats each autumn in preparation for their non-stop flight to Suriname, South America. Four areas of the upper Bay of Fundy have been designated as Ramsar sites. Similarly, the Alaksen Ramsar site on the Fraser River Delta on Canada's west coast supports internationally important shorebird populations in the Pacific flyway.

The extensive coastal plain and abundant rainfall of the southeastern United States supports a complex of large and heterogeneous wetlands that include the Great Dismal Swamp, the Pocosins, and Okeefenokee Swamp. The Great Dismal Swamp covers 850km2 near the Norfolk-Newport News-Virginia Beach urban sprawl. Originally it covered more than 2,000km2; but its area was reduced by draining, logging and fire. Former owners donated 250km2 to the U.S. Government to establish a national wildlife refuge.

The Pocosins are found on the Atlantic Coastal Plain from Virginia to northern Florida; these are wetlands dominated by evergreen shrubs such as Cyrilla racemiflora, Magnolia virginiana, Persea borbonia, Ilex glabra, Myrica heterophylla, Smilax laurifolia and pine Pinus serotina. In North Carolina the Pocosins cover 3,700km2. Okeefenokee Swamp in southeastern Georgia and northeastern Florida is a mosaic of wetlands encompassing 1,750km2. Much of this swamp is now part of the Okeefenokee National Wildlife Refuge, established in 1970.

The southern tip of Florida contains three major wetland types in a 34,000km2 wetland complex: the Everglades, Big Cypress Swamp, and numerous coastal mangroves and glades. Water flows from Lake Okeechobee to the sea as a thin sheet (often centimetres in depth), forming an 80km wide 'sea of grass' dominated by Cladium jamaicense (actually a sedge).

Extensive marshes, swamps and shallow coastal lakes exceed 36,000km2 within the Mississippi River Delta. This is a staging and resting area for one of the most important waterfowl flyways in North America. The delta provides habitat for geese, ducks, and American Coot Fulica americana and hundreds of thousands of shorebirds that overwinter or pass through on their way to their wintering grounds in Latin America.

Coastal estuarine wetlands are found along the Atlantic, Pacific, Alaskan and Gulf coasts. Saltmarshes are particularly abundant along the Atlantic and Gulf coasts. Mangrove swamps, dominated by halophytic shrubs or trees, are found in southern Florida.

There are more than 125 coastal lagoons along Mexico's Atlantic and Pacific shorelines, encompassing a total surface area of about 12,400km2. Mangroves cover more than 6,500km2, one of the largest areas of mangrove coverage among tropical countries. The 2,970km east coast of Mexico contains some of the largest undisturbed wetland complexes in the Western Hemisphere. Among these are the Laguna Madre, Tampico lagoons and marshes, Laguna Tamiahua, Alvarado lagoons, Tabasco lagoon and marshes and the coastal lagoons of Campeche and Yucatán. The Pacific Coast of Mexico also contains important wintering areas for North American waterfowl.

Threats to North American Wetlands

Historically, conversion of wetlands for agricultural use (drainage) has been the major factor behind wetland decline in Canada, Mexico and the United States. In urban areas filling has accounted for significant wetland losses. Construction of dams, canals, waterways, levees and flood control structures has had serious downstream effects in many places. For example, along the coast of Louisiana, in the United States, more than 100km2 of wetlands are lost annually due to subsidence and erosion as a result of water diversions and sediment deprivation.

In Canada, over one-seventh of the wetland area that existed before European settlement has been converted for other uses. In the United States (excluding Alaska) it is likely that over 50% of the original wetland area has been lost while Mexico's loss is estimated at approximately 35%.

Public awareness and wetland conservation efforts have increased in recent years and new laws stimulating wetland programmes have had positive influences on wetland management. However, it is apparent that the cumulative impact of many small individual actions (no single one of which is alarming) is becoming a major threat to the integrity of wetland landscapes. Unfortunately, no methodology for cumulative impact assessment is universally accepted by scientists and wetland managers.

The North American Waterfowl Management Plan (signed in 1986) is an innovative approach between Canada and the United States to protect and improve waterfowl habitats on a continental scale. In 1994 this plan was revised and Mexico joined the United States and Canada as a signatory. As of April 1995 nearly 810,000ha of wetland habitats have been protected and over a million hectares have been restored or enhanced in North America as a result of the implementation of this plan.

Case Studies of North American Wetlands

The biodiversity of wetland ecosystems in North America is illustrated by the four case studies described in this chapter: Old Crow Flats, Canada; Quill Lakes, Canada; Ría Lagartos, Mexico; and Caddo Lake, United States.

Arctic wetlands include innumerable shallow lakes and ponds that dot the tundra and the marshes during the summer, and shallow-water wetlands along the coasts and in low-lying areas. Old Crow Flats (Case Study 1) is an extensive wetland complex covering the Old Crow River Basin and the Bluefish River Basin in northern Yukon. Over 2,000 wetlands dot the landscape. Low average annual precipitation and average annual daily temperature make this wetland complex unique.

Quill Lakes (Case Study 2) is an exceptionally diverse area that includes two saline lakes, several freshwater marshes, native prairie habitat, and some of the best pothole areas in the Province of Saskatchewan. Every year this area is used by nearly one million birds; it provides excellent habitat for waterfowl as well as a seasonal home for more than 150,000 shorebirds.

In Mexico, much of the Yucatán Peninsula is a calcareous plain with subterranean water courses that surface near the coast and give rise to a series of coastal lagoons and marshes. This chain of saline lagoons and small estuaries along the north shore of the peninsula supports a large breeding population of Caribbean Flamingos Phoenicopterus ruber. Ría Lagartos (Case Study 3) is the largest wetland complex on the east coast of the Yucatán Peninsula, containing two large shallow sea bays fringed by extensive mangrove swamps, studded with numerous mangrove covered islands.

The large shallow wetland which once covered the northern parts of the Mississippi River Basin has long since been drained for agriculture and the basin's most important wetlands are now the lowland floodplains of rivers and streams. Caddo Lake and its associated wetlands (Case Study 4), is one example, hosting wetland forest communities with such species as willow Salix spp., aspen Populus spp., ash Fraxinus spp., elm Ulmus spp., and hickory Carya spp., in addition to cypress and aquatic communities supporting a range of emergent and submerged aquatic plants. The wetlands of this basin serve as the most important wintering area for ducks and geese in the whole of the central part of the continent and provide staging and resting areas on the most important waterbird flyway in North America.

Case Study 1: Canada

Old Crow Flats, Yukon Territory

By Jim Hawkings, Canadian Wildlife Service, Canada

Major Features of the Wetland

Old Crow Flats, located in the extreme northern Yukon Territory, is a lacustrine plain pocked by over 2,000 wetlands. The wetlands occur in two sub-areas, the Old Crow River Basin, and the Bluefish River Basin. Located north of the community of Old Crow, the Old Crow River Basin is the largest, covering 550,000ha, 26% of which is wetland (open water, emergent vegetation, or floating mats). The Bluefish Basin lies south of Old Crow and covers 83,000ha, 21% of which is wetland. The lakes in the Old Crow Flats vary in size from 0.5 to 4,700ha and have an average depth of 1 to 1.5m and a maximum depth of about 4m. The basin is composed of lacustrine clays deposited during the Quaternary when the basin was flooded by an enormous lake, and overlain by varying depths of organic material which have accumulated since this glacial lake drained about 12,000 years ago. Over the years, streams in the basin have cut deep into the sediments, leaving most of the lakes perched well above the highest spring flood level. The abundant shallow water, 24 hour daylight, and warm summer temperatures make the present lakes exceptionally productive for this latitude.

This image, covering 120km by 120km, was derived from data collected by the Thematic Mapper sensor on the Landsat 5 satellite on 30 June 1990. The Old Crow River Basin covers the upper half, and the Bluefish Basin is the lower right. In this false-colour infrared enhancement, clear water appears as black and turbid water as shades of blue. Note that the large lakes are generally oriented at right angles to the prevailing northeast winds. Dark green tones indicate various types of open canopy spruce forests. The red tones indicate broad-leaved deciduous plants, principally willow, dwarf birch, and various ericacious shrubs. The brightest white and light grey tones indicate barren or sparsely vegetated terrain on mountains surrounding the basins as well as seasonally flooded gravel bars along the rivers. The small community of Old Crow is the only human cultural feature visible. Its airstrip and gravel streets appear as a bright barren area at the confluence of the Porcupine River (draining northeast to southwest across the lower half of the image) and the Old Crow River (meandering northwest to southeast). (Photo: J. Hawkings)

The Old Crow Flats constitutes its own ecoregion within the Taiga Cordillera ecozone of Canada. The mean annual precipitation is 200mm, and mean annual daily temperature is -10°C, with July mean daily temperature 15°C and January mean daily temperature -35°C. This makes it one of the warmest locations in the Yukon in summer and one of the coldest in the winter. The entire area is underlain by permafrost, and growth and decay of ground ice constantly modify the landscape.

The lakes are formed and modified by the combined action of permafrost and the prevailing winds. They appear to go through cycles of draining and refilling, with flushes of productivity at several stages, but the dynamics of this process are not completely understood. Although the lakes are constantly changing in depth and area, this is a gradual process compared to the year to year fluctuations in more temperate or tropical wetlands or in other northern areas subject to seasonal flooding. This makes the Flats a predictable and attractive destination for waterfowl.

Fauna and Flora of Old Crow Flats

Many of the lakes have luxuriant beds of submergent plants such as pondweeds Potamogeton spp., burreeds Sparganium spp., and even duckweed Lemna spp. The terrestrial vegetation is a mixture of shrubs such as willow Salix spp., Dwarf Birch Betula glandulosa, Labrador Tea Ledum decumbens, and lowbush Cranberry Vaccinium vitis-idaea, sparse White Spruce Picea glauca and Black Spruce P. mariana forest with shrub or lichen understorey, and subarctic tundra dominated by Cottongrass Eriophorum vaginatum or Sphagnum mosses.

More than 100 bird species have been recorded on the Flats, including at least 21 species of waterfowl. The area is important as a breeding and moulting ground to some 500,000 waterfowl including ducks (see Box 10), swans, geese, three species of loon Gavia spp. and a variety of other waterbirds. Banding studies have shown these birds to be associated with all four North American Flyways. Waterfowl are more concentrated here than at other locations in the north. For example, densities of ducks on the Flats are usually in the vicinity of 80 ducks per square kilometer, two to three times higher than in any of the 11 primary waterfowl breeding grounds surveyed annually in Alaska by the US Fish and Wildlife Service. Some of these birds breed and moult on the Flats, while others such as Barrow's Goldeneye Bucephala islandica do not breed there but come in midsummer from further south to undergo their annual moult.

The dominant mammal of the Flats is Muskrat Ondatra zibethicus, which is present in densities of up to 4.5 per hectare in spring and 9 per hectare in fall, a total population of 330,000 to 650,000. Moose Alces americana are also present and, in habitats such as drained lake basins colonized by dense thickets of willow, they are abundant. The Porcupine Caribou Rangifer tarandus herd migrates in and around the Flats in spring and fall and some animals are present in the winter. Larger carnivores including Red Fox Vulpes vulpes, Wolf Canis lupis, and Grizzly Bear Ursus arctos are also part of the Old Crow Flats ecosystem.

Traditional Utilization and Management of the Area

The waterfowl, muskrats, and other wildlife of the Flats as well as caribou and salmon are of great importance to the native people of the community of Old Crow, located just south of the Flats at the confluence of the Old Crow and Porcupine rivers. These people are descendants of the first human inhabitants of the area some 20,000 years ago, and are known as the Vuntut Gwitchin, which means 'people of the lakes'.

In 1982 Old Crow Flats was designated a Ramsar site. Under the terms of the Vuntut Gwitchin Final Agreement proclaimed by the Canadian Government in February 1995, the northern portion of the Old Crow Flats becomes Vuntut National Park. Of the remainder, part is Settlement Land belonging to the Vuntut Gwitchin First Nation, and the rest remains federal government land. Despite these three different land tenures, the land claims agreement designates the entire area as Old Crow Flats Special Management Area and stipulates that it be managed to maintain the integrity of the area as one ecological unit, with the conservation of fish and wildlife and their habitats, and the protection of the current and traditional use of the area by the Vuntut Gwitchin as guiding principles. Using these principles, a management plan will be prepared jointly by government and the Vuntut Gwitchin which incorporates the management plan for the Vuntut National Park.

Given the remote wilderness location, pristine conditions, and the strong conservation regime now in place for the Old Crow Flats, its future as a wetland of international importance seems politically assured. One potential threat is global climate change. Old Crow residents seem to feel that lake levels have been dropping, and are concerned that the Flats are 'drying up' from the warmer temperatures and earlier springs of recent years.

Case Study 2: Canada

Quill Lakes

By Saskatchewan Wetland Conservation Corporation, Canada

Location and Major Features

The Quill Lakes contains three distinct wetlands (Big Quill, Middle Quill and Little Quill lakes) and numerous small marshes within a mixed grassland ecosystem. The lakes are located approximately 120km north of Regina, Saskatchewan, the site of the 1987 Ramsar Convention Conference. The area, encompassing over 40,000ha, includes the largest saline lake in Canada, a freshwater lake, several marshes, mixed-grass prairie and aspen parkland. Migratory waterfowl breed, feed and roost on large open marshes adjacent to the lakes as well as on the lakes themselves. Wind action and annual fluctuation in water levels on these shallow lakes create large expanses of fresh mudflats (similar to tide action) used by shorebirds for feeding. The region is considered one of North America's most critical inland waterbodies for up to one million birds.

Typical freshwater marshes located adjacent to Quill Lakes. (Photo: Saskatchewan Wetland Conservation Corporation)

Regional and International Importance

Selected as a Ramsar site in 1987, Quill Lakes was the first implementation site for the North American Waterfowl Management Plan in Canada. As a 'first-step' initiative, nearly 7,000ha were developed or enhanced for waterfowl and other wildlife. Designation as a premier marsh under the Provincial Heritage Marsh Program involved intensified management of existing Ducks Unlimited Canada projects on tributary drainage.

The area was designated as a Western Hemisphere Shorebird Reserve Network site in 1994 - one of only three such sites in Canada. Membership in this Network brings additional international recognition to the Quill Lakes site, enhancing the capacity for conservation.

Species of Significance at Quill Lakes

The Quill Lakes region is a significant North American site for ducks, geese and shorebirds. Shorebird numbers peak in May and late July or early August; ducks and geese in September and October. The important roles played by Quill Lakes include:

-- major staging area for up to 500,000 ducks (primarily Mallard Anas platyrhynchos, and others including Pintail Anas acuta, Gadwall Anas strepera, Redhead Aythya americana, Canvasback Aythya valisineria and Scaup Aythya affinis);

-- major staging area for 250,000 geese (Snow Goose Anser caerulescens [or Chen caerulescens], Canada Goose Branta canadensis and White-fronted Goose Anser albifrons), and 40,000 Sandhill Cranes Grus canadensis;

-- nesting site for 400 - 500 White Pelicans Pelecanus erythrorhynchos (at Middle Quill Lakes);

-- up to 150,000 Arctic-nesting shorebirds have been observed in a single-day count (in 1993) including over 30 different species. The most common migratory visitors include Red-necked Phalarope Phalaropus lobatus, Semi-palmated Sandpipers Calidris pusilla, Sanderling Calidris alba and Stilt Sandpiper Micropalama himantopus [or Calidris himantopus],

-- breeding site for up to 300 Piping Plover Charadrius melodus, a threatened species (IUCN Red List, 1994);

-- habitat for several other threatened and endangered species, including the Whooping Crane Grus americana (IUCN Red List, 1994), Baird's Sparrow Ammodramus bairdii, Ferruginous Hawk Buteo regalis and Peregrine Falcon Falco peregrinus.

Threats and Management Solutions

The Quill Lakes region is classified as a saline lowland range. Natural fluctuation in water levels and potential long-term decline in water level on the lakes pose the largest threat. Up until recent years, cattle grazed in many upland areas associated with the lakes, and had access to shorelines, beaches and mudflats which resulted in the destruction of critical habitat for wildlife. Uneven cattle distribution contributed to increased grazing pressure near water sources, and the saline environment appeared to be responsible for patchy cover in several locations.

To address these concerns, waterfowl management plans were developed to guide conservation partners in restoring and protecting areas. The plans feature sound land-use initiatives that contribute to soil, water and wildlife conservation. A shorebird habitat management plan is in the final stages of preparation. By working with local landowners, who are primarily cattle producers, the Saskatchewan Wetland Conservation Corporation and its partners ensure that producers' needs are taken into consideration at the planning and implementation stage, and that the area is restored and enhanced in a mutually beneficial manner for both wildlife and cattle producers.

It is recognized that the support and participation of local landowners and farmers is crucial to the success of the project. Many of the solutions to prairie soil conservation problems also apply to increasing waterfowl populations. To be acceptable, solutions must be sound from a conservation perspective, and economically fair to landowners and producers in the Quill Lakes area.

Elements of the waterfowl management plan include a Waterfowl Crop Damage Control Program, the acquisition of 12,141ha of land around the Quill Lakes and the construction of fences to reduce conflict between cattle and nesting birds, particularly on the beaches of Big Quill Lake where 19% of the provincial population and 5% of the world's Piping Plover population nest. Managed grazing systems, incorporating rest-rotational and deferred grazing applications, are being implemented by local landowners to ensure that paddocks within the pastures will not be grazed until the nesting season is over. At least one paddock per pasture will not be grazed each year.

Mutual Benefits

Managing pastures will benefit producers by improving range conditions and vegetative cover thus ensuring a sustainable supply of forage for cattle. Increased vegetation will benefit wildlife by improving nesting habitat for grassland nesting birds. The Quill Lakes project will also provide a unique economic opportunity for local individuals to capitalize on developing and marketing products which cater to segments of the burgeoning eco-tourism industry. Nature tourism is one of North America's fastest growing industries and holds a great deal of potential for increased economic development activity in rural Saskatchewan in addition to the economic impact of waterfowl hunting in many communities.

Case Study 3: Mexico

Ría Lagartos, Yucatán

By Mauricio Cervantes, Wetlands International, Mexico

Major Features

The Ría Lagartos estuary is located 270km from Mérida, the capital of the province on the northeast coast of the state of Yucatán. It has a surface area of 55,350ha and extends along 74km of coastline. The north border is formed by a sand bar island with three connections to the sea. The system is composed of three water bodies differing in length from 0.25 to 3.5km. The estuary extends over an area of 9,467ha and the depth varies from 0.5 to 3m. The climate varies from the very dry arid to the very dry warm-humid and the area is located in the path of Caribbean hurricanes. The whole area is a relatively flat land supporting an interesting range of plants and animals associated with coastal ecosystems.

The area is also of archaeological interest: during the Maya civilization this area, previously part of the Chikinchel province, controlled the production of salt for the entire nation. Salt production is still an important source of income along with fisheries for the 1,500 families in the four villages nearby.

Flora and Fauna of the Area

The main flora associations in the Ría Lagartos include:

-- the vegetation of the coastal dunes, composed mainly of xerophitic plants such as Nakax Palms Cocotrinax readii, Chit Thrinax radiata, and the Kuká Palm Pseudophoenix sargentii (these three species are considered as threatened in Mexico);

-- the mangroves, composed of Rhizophora mangle, Languncularia racemosa, Avicennia germinans and Conocarpus erectus;

-- the tropical xeric (dry) forest running parallel to the coast, composed of Pseudophoenix sargenti and cacti;

-- the marsh association which is widely distributed, with the association of Phragmites australis, Caldium jamaicensis, Typha spp. being dominant;

-- the 'petenes' - islands of tall forest of several species growing in concentric rings forming a dome . From the centre to the edge of the dome the tree species include Metopium, Ficus, Plumeria, Manilkara, Thrinax, Sabal and Haematoxylon campechianum.

The fauna includes 391 species of vertebrates, of which 142 are endemic to Mesoamerica (Central America and Mexico), 15 endemic to Mexico and 1 endemic to Yucatán. Thirty three of these vertebrates, including species of birds, mammals and reptiles, are considered threatened in Mexico.

The Greater Flamingo, which breeds here, is the symbol of the Ría Lagartos reserve. (Photo: Mauricio Cervantes)

The area is considered outstanding for birds, with a total of 72 migratory and 141 resident species. The symbol of the reserve is the Greater Flamingo Phoenicopterus ruber ruber and the area is an important nesting site for this species. There are 50 species of reptiles, including the snakes Aqkistrodon bilineatus and Boa constrictor. Four species of marine turtle lay their eggs on the beaches, Hawksbill Turtle Eretmochelys imbricata, Green Turtle Chelonia mydas, Loggerhead Caretta caretta, and Leatherback Dermochelys coriacea; all are threatened species (IUCN Red List, 1994). A wide variety of fish inhabit the 'cenotes' of the reserve (depressions in the ground which retain water even when the rest of the wetland has a low water level) including two endemic species, Typhliasina pearsei and Ophisthernon infernale.

Main Threats to the Area

The main natural threat confronting both the reserve and the local population is the risk of flooding through waves and surge tides produced by hurricanes and storms in the Gulf of Mexico. In 1988, hurricane Gilberto broke the sand bar and the damage inflicted on the area prompted the Mexican Government to request that the Ría Lagartos be included on the Montreux Record. Although sites are usually placed on the Record because of undesirable ecological changes resulting from human rather than natural causes, this request was granted. In 1993 the Mexican Government requested that the site be retained on the Montreux Record because of a number of new activities in the area which threatened the integrity of the ecosystem including salt extraction and illegal fishing and farming. A management plan has been prepared and with partial funding from the Global Environment Facility it is beginning to be implemented. It is hoped that this will eventually lead to the removal of Ría Lagartos from the Montreux Record.

Current Status and Future Management

In 1979 Ría Lagartos was given legal protection mainly to safeguard the colony of the Greater Flamingo and in 1986 it was designated a Ramsar site. In 1988 it was re-categorized as a Biosphere Reserve within the framework of the Man and the Biosphere Programme. A corridor has been established along the coast of the state linking Ría Lagartos with another three reserves and there are plans to extend this corridor along the whole peninsula of Yucatán.

Recently, three more Mexican wetland areas have been designated Ramsar sites. A National Wetlands Programme is being implemented, with the objective of meeting the challenges of sustainable development, conservation and adequate management of the natural resources of the wetlands in the country.

Case Study 4: United States of America

Caddo Lake

By Dwight K. Shellman, Jr. and Roy G. Darville, Caddo Lake Institute, Inc., USA.

The Cypress Valley Watershed occupies approximately 17,400km2 in all or part of eleven Texas counties and one Louisiana parish. Caddo Lake, lying 240km east of Dallas, Texas, is the centrepiece of the watershed and without doubt is one of the most biologically diverse areas in Texas. Approximately 3,300ha of the lake and surrounding wetlands were designated a Ramsar site in 1993, becoming the thirteenth such site in the USA.

The Caddo Lake Institute, a private operating foundation, has played a key role in the designation of the wetland as a Ramsar site and continues in its broader role as an 'ecosystem-specific' NGO and sponsoring entity, underwriting local wetland science and conservation education, as well as cultural and ecological research and monitoring. The Institute's Caddo Lake Scholars Program has created and provided specialized wetland science training to local colleges, public school educators and students, using the Caddo Lake wetlands as a living laboratory and classroom.

Diversity of Plant and Animal Life at Caddo Lake

A summary of the available information on the vertebrate life recorded at Caddo Lake and its associated wetlands is shown in Box 11. In terms of its plant life, 189 species of trees and shrubs, 42 woody vines, 75 grasses and 802 other herbaceous plants have been identified in the Caddo Lake wetlands and 48 of these species are mainly restricted to hardwood bottomlands and associated wetlands. The watershed is the home of 44 animals, plants or plant communities considered endangered, threatened or rare by Texas Parks and Wildlife Department. Twenty four vertebrate species indigenous to the area are on federal endangered or threatened listings.

Bottomland hardwoods constitute a major vegetation cover within the Cypress Bayou-Twelvemile Bayou Basin, an area which includes Caddo Lake and its wetlands. Two distinct bottomland cover types are recognized: Baldcypress swamp/ flooded hardwood forest and bottomland mixed hardwood forest.

Baldcypress swamp/ flooded hardwood forest occurs throughout the Caddo Lake watershed. The vegetation is dominated by the Southern Baldcypress Taxodium distichum, a large, broad-based (buttressed) coniferous tree which is considered a pioneer species of southern wetlands. The trees are slow growing, but once they establish themselves in monocultural stands of even-aged cohorts, they are able to occupy permanently flooded areas. Trees of 250 to 350 years of age are not uncommon in the Caddo Lake ecosystem and the reported longevity elsewhere of this species can exceed a thousand years.

Although Baldcypress dominates the swamps, several other major species are associated with it such as Water Oak Quercus nigra, Willow Oak Q. phellos , and Water Tupelo Nyssa aquatica. There is also a great diversity of wetland shrubs, sedges, and rushes as well as 42 species of floating and submerged macrophytes.

Cypress swamps in general are highly productive ecosystems and the community at Caddo Lake represents one of the best examples of its kind in the state, supporting many animal species restricted to wetlands such as American Alligator Alligator mississippiensis, Alligator Snapping Turtle Macroclemys temminckii, Beaver Castor canadensis, Muskrat Ondatra zibethicus and Mink Mustela vison. The swamps are also of considerable importance as wintering and production areas for waterfowl especially Wood Duck Aix sponsa and Mallard Anas platyrhynchos, but including significant numbers of Northern Pintail Anas acuta, Gadwall A. strepera, American Wigeon A. americana, and Green-winged Teal A. clypeata.

Mixed bottomland hardwoods occur along streams and tributaries and are the most extensive of the two main vegetation types. Water and Willow Oak are the dominant species here, but they are associated with many other tree species and a variety of other plants. This type of vegetation contains areas of old growth and virgin hardwoods and one of the largest and most remarkable examples of such areas is found within the 3,400ha Longhorn Army Ammunition Plant (LHAAP), a federally-owned facility located on the southerly shores of Caddo Lake. The most significant of its forested wetlands is the Harrison Bayou virgin/old-growth bottomland forest. This 510ha forest has been characterized as a model southern bottomland hardwood wetland in both structure and ecological function. Approximately half of the Harrison Bayou forest is virgin forest and the balance is naturally regenerated, old growth, bottomland mixed forests.

These bottomlands are not only important areas for forest dwelling species such as White-tailed Deer Odocoileus virginianus, Raccoon Procyon lotor, Swamp Rabbit Sylvilagus aquaticus and Barred Owl Strix varia, but also provide habitat for resident waterfowl and function as an important migratory corridor for waterfowl which use the area for cover, resting and feeding. In addition, they serve as a haven for over 50% of all neotropical migrant songbirds listed by the US Fish and Wildlife Service as occurring in North America.

This forest community is significant when one considers that the US has lost approximately 50% of the wetland acreage that existed in the lower 48 states prior to European settlement and that between 1883 and 1991 the southern bottomland hardwood forest acreage decreased by 77%. The 23% that remains is being fragmented and has lost much of its original ecological role.

Caddo Lake and its associated wetlands are home to many species or plant communities which are of special concern. Globally threatened species include Red-cockaded Woodpecker Picoides borealis, Piping Plover Charadrius melodus and Alligator Snapping Turtle (IUCN Red List, 1994) and there are many other species which are either Federally or Texas listed.

Threats to the Caddo Lake Wetlands

Cypress swamps are very fragile and are becoming increasingly scarce within the state as a result of any number of activities such as timber harvesting, channelization and other land-use activities which alter the hydrologic conditions in ways which preclude regeneration of the key species, the Southern Baldcypress. This species is unable to regenerate on a permanently flooded substrate and the seedlings cannot tolerate long periods of complete submergence; successful regeneration is believed to be dependent upon appropriate flooding and drying patterns . At Caddo Lake mature trees are surviving the current permanent inundation, but there is little regeneration taking place in permanently flooded areas. The alleged low regeneration rates elsewhere are the subject of studies by the National Biological Service and the Caddo Lake Institute.

Populations of American Beaver Castor canadensis, and an introduced species of Nutria Myocastor coypus are regarded as potential risks to healthy generation and regeneration of old-growth and Baldcypress forest remnants and do not seem to be well controlled by predators in the area. Nuisance macrophytes include duckweed Lemna sp., Hydrilla Hydrilla verticillata, Water Hyacinth Eichhornia crassipes, and water lilies Nuphar luteum and Nymphaea odorata. There is also concern about elevated levels of heavy metals such as mercury, cadmium, lead and selenium.

In 1995, Texas state authorities advised against frequent consumption of Largemouth Bass because of the mercury levels detected in tissue samples of this fish. Elevated levels of fecal coliforms were found in the course of preliminary testing near small lakeshore communities by the Caddo Lake Institute 1995 monitoring activities.

The Caddo Lake Institute's Scholars Program Awards Ceremony in May 1993 included the first 'State of Caddo Lake' announcement. In it Dr Jack McCullough compared his 1993 study findings with a similar study conducted in the 1980s. He recommended that additional efforts be made by appropriate agencies to control nutrient input into the lake because their levels appeared to be increasing, leading to an accelerated rate of eutrophication. He also urged that oil production in portions of the lake be monitored to insure minimal impact on the ecosystem.

His final remarks provide a fitting conclusion to this case study:

"In summary, I might say again, it is a fragile ecosystem. It is under stress. Efforts to alter the ecosystem through new construction projects - such as channelization, plans to raise the water depth or alter the hydraulic retention time - or any additional efforts to greatly increase development around the lake, should be controlled carefully, so we don't push this fragile system to the breaking point."

Further Reading

• Campo, Joseph J. 1986. The Big Cypress Wildlife Unit: A Characterization of Habitat and Wildlife. F.A. Series No. 25. Texas Parks and Wildlife Department: Austin, Texas.
• Cloud, Tom. 1993. Caddo Lake: A Unique Wetland Ecosystem. A Delineation of Resource Category 1 Habitat. U.S. Fish and Wildlife Service: Arlington, Texas.
• Cloud, Tom and Watson, Russell. 1991. Planning Aid Report -- Red River Waterway, Shreveport to Daingerfield Reach. U.S. Fish and Wildlife Service: Arlington, Texas.
• Crowley, C.M. 1993. A Study of the Ecological Integrity of Caddo Lake, Texas and Louisiana. Stephen F. Austin State University: Nacogdoches, Texas.
• Dahl, Tom E. 1990. Wetland Losses in the United States, 1780s to 1980s, U.S. Department of the Interior, Fish and Wildlife Service, Washington, D.C.
• Shellman, Dwight K. and Darville, Roy. 1995. Initial Species Inventory for Longhorn Army Ammunition Plant, Karmack, Texas. Caddo Lake Institute: Marshall, Texas.

CHAPTER 8

THE OCEANIA REGION

An Overview of the Wetlands in Oceania

By Roger Jaensch, Wetlands International - Oceania Program, Australia

The Region's Physical and Political Diversity

Oceania comprises Australia, New Zealand, Papua New Guinea (PNG) and the islands of the tropical Pacific, thus embracing a continent nation as well as some of the world's smallest island nations.

Most of Australia is relatively flat and geologically stable. In contrast, the large islands of Oceania are mountainous, and volcanic activity and earthquakes are commonplace. Snow-capped peaks occur in New Guinea above an altitude of 4,000m and there are many glaciers in New Zealand. Hundreds of low islands and, in some cases entire countries, are founded on coral reefs. Although Australia has its 'wet tropics', the interior is generally arid, whereas the west coast of New Zealand is especially rainy and annual rainfall in the PNG highlands can be up to 10,000mm.

Ramsar's Oceania Region includes 16 independent countries, three of which are Contracting Parties to the Ramsar Convention. Australia and New Zealand are industrialized and rich in natural resources, with relatively stable economies and high standards of living. PNG, the Solomon Islands and arguably others, possess substantial natural resources but lack the infrastructure and human resources to move beyond developing country status. The smaller island nations are poor in natural resources except for the largely untapped wealth in the seas within their huge Economic Exclusion Zones. There are eight external territories in Oceania, divided among France (New Caledonia, Wallis and Futuna, French Polynesia), the United States (Northern Mariana Islands, Guam, American Samoa) and Great Britain (Pitcairn).

Wetland Types and Threats

Ephemeral lakes and swamps are abundant in the internal drainage systems of central Australia and fill at irregular intervals from massive flood events. Best known is Lake Eyre, which covers one million hectares and is up to 6m deep when full but normally is dry with a salt crust up to 50cm thick. Few people live in Australia's interior but extensive grazing by cattle and sheep has caused increased run-off, erosion and sedimentation in many catchments.

Seasonal wetlands of Oceania include the biologically-rich tropical floodplains of northern Australia and PNG (e.g. the Ramsar-listed Kakadu and Tonda wetlands) and lakes and swamps on coastal plains in the Mediterranean climatic zone of southern Australia (e.g. Forrestdale Lake, Bool Lagoon: both Ramsar sites). The tropical floodplains are threatened by the rapid spread of introduced species, notably exotic weeds in Australia and deer and fish in PNG; many of the temperate wetlands are affected by pollution and competing demands on water supplies.

Lake Pangua, Fly River floodplain, Papua New Guinea. This tropical floodplain supports populations of crocodiles and fishes which are harvested for both subsistence and commercial purposes. (Photo: Roger Jaensch/Wetlands International)

Permanent lakes occur in the Pacific in volcano craters (e.g. Lake Letas, Vanuatu), on raised coral atolls (Lake Te-Nggano, Solomon Islands) and where meandering lowland rivers block their own tributaries (Lake Murray, PNG: 64,700ha). Lakes blocked from the sea by sand-drift are common on the Australian coast (e.g. Lake Alexandrina) and highland valley lakes abound in New Zealand (e.g. Lake Te Anau). Due to low populations and remote locations, Pacific island lakes are relatively undisturbed, but many coastal lakes in Australia and New Zealand are foci for urban areas and have been seriously degraded due to reclamation, pollution and altered hydrological regime.

Oceania also has freshwater wetland forests. Paperbark Melaleuca spp. dominated swamp forests are a feature of northern Australia, sago palm Metroxylon sagu and Terminalia brassii swamp forests occur in PNG and the Solomon Islands, and diverse tropical forests stand in seasonally inundated wetlands on most of the larger Pacific islands. The Melaleuca forests are threatened by excessive burning and some tropical swamp forests are subject to unsustainable logging.

Mangrove forests occur on all sides of Australia which has the third largest mangrove area in the world, after Indonesia and Brazil. In the Pacific islands especially large, mostly undisturbed forests occur in PNG (Gulf of Papua 200,000ha) and other extensive areas are found in the Solomon Islands and Fiji. At Lake MacLeod in Western Australia, mangrove communities exist 15km inland, connected to the sea only by subterranean movement of seawater. Most of the human population of Oceania live in the coastal zone which results in considerable pressure on mangroves, especially in southern and eastern Australia and near urban centres in the Pacific islands. In one of the case studies from the region the relatively pristine and highly diverse mangroves of Hinchinbrook Island, off the Queensland coast, are described; tourism development is one of the more serious threats to part of this mangrove area. In Fiji, mangroves are among the few areas available for development and are being lost to agriculture and tourism projects.

The most celebrated of Oceania's coastal wetlands are its coral reefs, particularly the Great Barrier Reef of eastern Australia (1,600km), which together with the barrier reefs of New Caledonia (1,140km), are by far the world's longest barrier reefs. The coral reefs (barrier, patch, fringing and atoll formations) throughout Oceania provide vital subsistence resources for humans, especially in the smallest island groups. Reefs of Oceania are threatened by a trend towards unsustainable subsistence and commercial fishing, degradation from the siltation effects of upland logging on islands with steep mountains, heavy ecotourism pressures in some areas, and (locally) by urban pollution heightened by rapid population increase.

Shallow estuaries and bays are conspicuous around Australia and especially in the North Island of New Zealand. Many are the mainstay of major commercial fisheries. Worthy of special mention in this regard is Shark Bay, a World Heritage site in Western Australia, which also has large hypersaline embayments that support stromatolite (algal mound) formations of considerable scientific interest. Of some concern is the Waikato Estuary in New Zealand which has been affected by altered hydrology due to hydroelectric development in the Waikato River catchment.

New Zealand is notable for its high country cushion bogs and lowland raised bogs, notably the Ramsar listed Kopuatai Peat Dome (10,201ha). Smaller bogs are scattered through the region, some being on mountains of small Pacific islands. The peatlands which form part of the Waituna Wetlands in New Zealand are the subject of one of the case studies and of particular interest is a cushion bog community occurring at sea level containing many alpine and sub-alpine species.

Notable occurrences of springs in Oceania are the mound springs of the Great Artesian Basin in central Australia and the thermal wetlands of New Zealand's North Island. Hose's Spring, on Christmas Island in the Indian Ocean, is one of Australia's Ramsar sites.

Biological Diversity of the Wetlands of Oceania

Wetland plants of the Pacific islands in general are poorly documented. However, it is known that of the 3,250 vascular plant species recorded from New Caledonia, about 75% are endemic and many occur in the Plaine des Lacs wetland. Wetlands in Australia (especially the southwest) support numerous endemic plant species including trees and shrubs (Eucalyptus, Banksia, Agonis, Callistemon, Melaleuca spp.), sedges and ground orchids. New Zealand wetlands also support a considerable number of endemic plant species, including some which are adapted to oligotrophic (low nutrient) conditions. Species that occur widely in other regions, especially Asia (e.g. lotus Nelumbo nucifera), are also present. In the Pacific islands, mangrove communities decrease in diversity from west (around 20 tree species) to east (a few species); affinities are with Asian species except the mangle Rhizophorasamoensis which is allied to American species.

Of special interest among the wetland mammals of Oceania is the threatened Dugong Dugong dugon (IUCN Red List, 1994): one of the world's largest populations survives in Australia's Shark Bay. Fruit bats are common in tropical wetlands; concentrations estimated at up to 250,000 have been recorded in flowering Melaleuca swamp forests in northern Australia. A peculiar egg-laying marsupial, the Platypus Ornithorhynchus anatinus, feeds underwater in streams of southeastern Australia.

Wetland reptiles are generally well represented in Oceania. The threatened Saltwater Crocodile Crocodylus porosus (IUCN Red List, 1994) occurs in Australia and PNG, where commercial harvest of animals and eggs occurs, and small populations persist in several Pacific islands such as Palau. Separate species of freshwater crocodile occur in Australia and PNG. File snakes Acrochordus spp. are seasonally abundant on the tropical floodplains: they are hunted in PNG to prepare drum skins. Although marine turtles are declining in many islands due to over-harvesting and disturbance to nesting beaches, the region still has good populations of most species. The case study on the Arnarvon Islands in the Solomon Islands describes the conservation efforts at one of the largest nesting sites for the threatened Hawksbill Turtle Eretmochelys imbricata (IUCN Red List, 1994). Frogs are found even in desert wetlands of Oceania and the colourful Corroboree Frog Pseudophryne corroboree occurs in Sphagnum moss bogs in the Australian highlands.

More than 200 waterbird species occur in Oceania and all major waterbird groups are represented. The case study on Lake Gregory, northwestern Australia, highlights the spectacular numbers of waterbirds which can occur at desert wetlands: peak counts of 600,000 have been recorded in exceptional years with around 100,000 regularly occurring. About half of the waterbird species recorded in Oceania breed in Australia and many are endemic to the continent. Five duck genera are endemic to Australia and endemic duck species occur in the mountain streams of PNG and New Zealand. A small suite of waterbird species (e.g. the widespread Spotless Crake Porzana tabuensis) occurs in the Pacific islands; more than a dozen species are endemic but several are believed extinct.

Forty percent of the world's shorebird species, including more than 50 trans-equatorial migrants, occur in Oceania. More than two million shorebirds arrive each year from northeast Asia, via the East Asian - Australasian Flyway, and to a lesser extent from North America via the Pacific flyways. These include the greater part of the global populations of Latham's Snipe Gallinago hardwickii (using freshwater marshes), Great Knot Calidris tenuirostris (intertidal flats), Little Curlew Numenius minutus (permanent waterholes in tropical grasslands) and the threatened Bristle-thighed Curlew N. tahitiensis (reef flats of Polynesia and Micronesia) (IUCN Red List, 1994). Notable examples of shorebirds endemic to Oceania are Banded Stilt Cladorhynchus leucocephalus, which breeds, spasmodically, in large colonies in Australian salt lakes, and Wrybill Anarhynchus frontalis, which has a laterally asymmetrical bill ideal for extracting mayfly larvae and fish eggs from undersides of stones in New Zealand river-beds. The threatened Tuamotu Sandpiper Prosobonia cancellata (IUCN Red List, 1994) occurs only in the Polynesian islands and is close to extinction.

Due to geographic isolation, the freshwater fish fauna of Oceania is poor in species from the 'true' freshwater fish genera found in Eurasia but includes many endemics. PNG has more than 300 freshwater fish species, many shared with northern Australia, and rainbowfishes (Melanotaeniidae) and blue-eyes (Pseudomugilidae) are unique to the combined sub-region. Lake Kutubu, in the limestone highland of PNG, has 11 endemic fishes. Notable fishes of Oceania include the Australian Lungfish Neoceratodus forsteri, which can respire with lungs and gills and is related to species in Africa and South America, and the Salamanderfish Lepidogalaxias salamandroides of southwestern Australia, which survives under swamp-bed detritus when its blackwater acid-peat habitats are dry. New Zealand's endemic Black Mudfish Neochanna diversus is found in the Kopuatai Peat Dome (a Ramsar site) and has a limited distribution.

Many of the marine crustaceans in the region are important for subsistence (e.g. mangrove crabs Scylla spp. and Macrophthalmus spp.) and commercial fisheries (e.g. prawns Penaeus spp.). BLche-de-mer (sea cucumber) and Trochus are harvested but yields have declined in many countries.

Diversity of marine life generally declines from west to east in Oceania: reefs in the northwest, around Palau, are particularly rich. With more than 600 species of coral in the Pacific, the world's most biologically rich reefs occur in Oceania.

The Future Of Wetland Biodiversity in Oceania

Although human populations in Oceania are low in a global context, substantial threats to wetlands and their biodiversity nevertheless exist. Notable examples are fragile arid-zone wetlands starved of life-giving water and island mangrove and coral reef systems under pressure from fast increasing human use of limited resources. A fundamental strategy for reducing threats throughout Oceania will be to increase community appreciation of wetland biodiversity and community participation in wetland management. Management methods will vary according to land tenure systems: mainly state ownership in Australia and New Zealand but mostly customary ownership in the Pacific islands.

At present PNG is the only Contracting Party in the Pacific islands region. Recent efforts to demonstrate that membership of the Ramsar Convention has potential benefits for communities using mangroves and coral reefs has sparked interest in accession by several countries. However the capacity of conservation agencies of these countries to allocate staff time and resources to wetland issues remains low. Provision of appropriate support therefore should be a high priority for the Ramsar Convention, partner organizations and other relevant Conventions.

Further Reading

• Cromarty, P. (compiler) and Scott, D. (ed). 1996. A Directory of Wetlands in New Zealand. Department of Conservation, Wellington, New Zealand.
• Finlayson, M. 1991. Oceania. In: Finlayson, M. and Moser, M. (eds), Wetlands. Facts on File, Oxford.
• McComb, A.J. and Lake, P.S. (eds). 1988. The Conservation of Australian Wetlands. Surrey Beatty & Sons, Chipping Norton, Australia.
• McComb, A.J. and Lake, P.S. 1990. Australian Wetlands. Collins/Angus & Robertson, North Ryde, Australia.
• Scott, D.A. (ed). 1993. A Directory of Wetlands in Oceania. International Waterfowl and Wetlands Research Bureau, Slimbridge, U.K. & Asian Wetland Bureau, Kuala Lumpur, Malaysia.
• Usback, S. and James, R. (eds). 1993. A Directory of Important Wetlands in Australia. Australian Nature Conservation Agency, Canberra, Australia.

Acknowledgements

The author is grateful for constructive comments on this article contributed by Pam Cromarty, Joanna Ellison, Wendy Evans, Max Finlayson, Stuart Halse and Janet Owen.

Case Study 1: Australia

Mangroves on Hinchinbook Island

By Joanna Ellison, Australian Institute of Marine Science, Australia

Importance of the Site

Hinchinbrook Island is the largest island (393km2) off the Queensland coast. The terrain is mountainous, rising to 1,121m, and covered with dense rain forest. It is separated from the mainland to the west by the Hinchinbrook channel, which is fringed by 164km2 of mangroves, and a further 50km2 of mangroves occur in the leeward Missionary Bay to the north of the island. The island is a National Park, and the mangroves are in a relatively pristine condition.

Because of environmental variability in mangrove habitats at Hinchinbrook, the mangroves are unusually diverse, with 27 species commonly found. There is considerable diversity of forest character, both floristically and structurally, ranging from Red or Stilt-root Mangrove stands Rhizophora spp. attaining heights of above 20m near the waters edge, to stunted Yellow Mangrove thickets Ceriops spp. fringing extensive areas of uncolonized bare mud in parts of the upper intertidal zone. Grey and Large-leafed Mangrove Avicennia and Bruguiera spp. also dominate forest structure in particular locations. Towards the landward margins, conditions are found that uniquely favour individual species such as Looking-glass Heritiera littoralis, Black Lumnitzera spp., Cannonball Xylocarpus granatum and Yamstick Mangrove Scyphiphora hydrophyllacea.

Fresh and brackish swamp communities occur in narrow bands on poorly drained sites transitional between dryland vegetation and mangroves in Missionary Bay. These communities vary floristically according to local conditions, such as water depth and salinity, but typically include a tree canopy of Paperbark Melaleuca quinquenervia, with screwpine Pandanus spp., and a ground layer of sedges, grasses and ferns.

The fauna of the mangroves is highly diverse, including numerous species of microscopic and substrate infauna of great importance to the sediment chemistry and foodchains. More visible fauna include molluscs, crabs Sesarma and Uca spp., mud-skippers Periophthalmus spp., numerous snakes, Black Flying Fox Pteropus alecto and the threatened Estuarine Crocodile Crocodylus porosus and Dugong Dugong dugon (IUCN Red List, 1994) as well as numerous fish and birds.

Research at Hinchinbrook Island

In 1972 the Commonwealth Government of Australia created the Australian Institute of Marine Science (AIMS), located it at Townsville in North Queensland, and commissioned it with tropical marine research. Missionary Bay on Hinchinbrook Island was selected as a key mangrove research site because of its high diversity, pristine condition (owing to the National Park status of the island since the 1930s), and relative proximity to Townsville 100km to the south. A 400m boardwalk was constructed through the mangroves extending south from Coral Creek to facilitate regular access, taking months of labour, vessel support, and the skills of the Australian Army engineers. Since 1974 a range of research projects (see Box 12) has been carried out and the intensity of scientific effort at Missionary Bay has made it one of the best studied mangrove systems in the world, and the basis for expansion of research effort by AIMS to other sites in Queensland, N.W. Australia, Asia and the Pacific.

Adjacent to the Hinchinbrook channel about 6km south of Cardwell is Seafarm, the largest prawn pond operation in Australia. There are 60ha of 50 constructed ponds and 73 under construction to a total of 120ha, largely cleared from lowland Melaleuca forest. There is year-round production and discharge into the Hinchinbrook channel. This is monitored by both Seafarm and the Queensland Department of Environment and Heritage and maintained within tight limits set on nitrogen, phosphorous and suspended solid levels. This is a professionally run operation that has minimized its impact with on-farm management.

The whole of Hinchinbrook Island is a National Park, but the northern tip of Cape Richards is leased as a low-key tourist resort (up to 60 people), connected by a boat service to Cardwell. From here tourists can access the eastern coastal walk via a short boardwalk from the southeast corner of Missionary Bay mangroves to the Ramsey Bay beach.

Two kilometres south of Cardwell is Oyster Point or Port Hinchinbrook, the site of ongoing controversy regarding development of a large marina-resort. The 44ha site was purchased in May 1993, and a resort was proposed to accommodate 1,500 guests, and a 250 berth marina. Including earlier work by a failed developer, work at the site has achieved clearing of vegetation and mangroves along the foreshore, excavation of the marina basin, partial excavation of the channel within the site, construction of access roads, and commencement of beach formation works.

On 15 November 1994 the Governor-General, on the advice of the Federal Minister of the Environment, stopped work for a more thorough assessment of potential damage of the development to the Great Barrier Reef World Heritage Area which includes the Hinchinbrook channel. Two scientific workshops were called, and an assessment carried out to determine the environmental impacts of the developer's application to construct breakwaters, dredge an outer channel and implement a beach and foreshore management plan. This showed that there was potential to damage the World Heritage Area, mainly through sediment disturbance and effects on seagrass beds in the channel, and as a result the application to build breakwaters, a marina and an artificial beach was not granted, though the resort development was approved. In October 1995 a site assessment by the Great Barrier Reef Marine Park Authority indicated that moderate to severe erosion problems had developed at the partially cleared site, and recommended a foreshore monitoring programme.

Further Reading

• Clough, B.F. (ed). 1982. Mangrove Ecosystems in Australia: Structure, Function and Management. Canberra, ANU Press.
• National Environmental Consulting Services. 1995. 'Port Hinchinbrook'. Assessment of  Potential Environmental Impacts on World Heritage Property. Watson, ACT.
• Robertson, A.I. and Alongi, D.M. (eds). 1992. Tropical Mangrove Ecosystems. Washington DC, American Geophysical Union.
• Thorsborne, A. and Thorsborne, M. 1988. Hinchinbrook Island. Weldons Pty Ltd., McMahons Point.
• Thom, B.G. (ed). 1986. Coastal Geomorphology in Australia. Australia: Academic Press.
• Wolanski, E. 1994. Physical Oceanographic Processes of The Great Barrier Reef. Bola Raton, FLA: CRC Press.

Case Study 2: Australia

Lake Gregory

By Stuart A. Halse, Department of Conservation and Land Management, Australia

Lake Gregory is a large, semi-permanent lake system on the Great Sandy Desert, northwestern Australia. The contrast between the vast expanse of water, with its fringing trees and shrubs, and the surrounding spinifex-covered sand dunes of the desert, provides the main visual attraction of the lake. High numbers of terrestrial plant and animal species, as well as aquatic organisms, occur because of the availability of water.

Major Physical Features

Lake Gregory has a catchment of 65,000km2 that extends approximately 300km northeast out of the desert into an area of comparatively high monsoonal rainfall. Run-off generated in the catchment enters the lake via Sturt Creek, which breaks into a series of small channels as it approaches the lake. Despite annual evaporation of 3,900mm, Lake Gregory contains water about nine years out of ten. There is no outflow from the lake, other than some groundwater recharge, and large volumes of water are stored after the major inflow events that occur every few years. Sturt Creek forms the headwaters of an ancient river system that was cut off from the coast when desert dunes developed west of Lake Gregory during the Tertiary; lakes have occurred at the site of Lake Gregory since the late Cainozoic.

Lake Gregory consists of three parallel inter-connected chains of lakes with the largest and deepest waterbody, Mulan, being in the eastern chain. When flooded to its normal boundary, the system covers 380km2 and Mulan is approximately 5m deep. After major flooding, such as occurred in 1993, the system covers 1,300km2 and Mulan has a depth of 12m.

Salinity of water in the system varies from approximately 100mg/l in the western lakes after flooding to 80,000mg/l in Bulbi and Mulan as they dry. The western lakes probably always contain fresh, turbid water when inundated but the eastern lakes, and Bulbi in the central chain, vary from turbid and fresh to clear and saline according to water depth. Evaporation and a decanting process from the western and northern waterbodies towards Mulan and Bulbi are responsible for high salinities (> 20,000mg/l) observed in those waterbodies for approximately six months before the system dries. High pH (up to 11) is often recorded at Lake Gregory, probably as a result of photosynthesis, and levels of silica often exceed 30 mg/l. Water in the western lakes contains a high proportion of bicarbonate, whereas that in the eastern lakes is dominated by sodium chloride. The ratio of calcium/(bi)carbonate is usually <1, which is unusual in Australian arid-zone lakes.

Biodiversity of the Lake

Biological research at Lake Gregory has concentrated on documenting use of the system by waterbirds and aquatic invertebrates. Seventy one species of waterbird have been recorded, 21 of them breeding. Numbers exceeded 600,000 in March 1988 and 240,000 waterbirds were counted in August 1986, although it seems that most years numbers peak at about 100,000. Numbers are usually highest towards the end of the dry season, which lasts from May to October. Lake Gregory probably supports among the highest waterbird numbers of any non-marine wetland in Australia. Dominated numerically by ducks, especially Grey Teal Anas gracilis, Pink-eared Duck Malacorhynchus membranaceus and Hardhead Aythya australis, there are also high numbers of Little Black Cormorant Phalacrocorax sulcirostris, Eurasian Coot Fulica atra and sometimes migratory waders including Oriental Plover Charadrius veredus. Eight thousand active nests of Little Black Cormorant were recorded in 1986.

The large number of fish-eating birds in the system reflects the abundance of Spangled Perch Leiopotherapon unicolor. Lake Gregory also supports a rich invertebrate fauna; the list of 175 species exceeds that recorded for any other arid-zone lake in Australia. Most of the invertebrates in the system are relatively small with insects, crustaceans and rotifers being the dominant taxonomic groups. Very few halophilous species of invertebrate (those which thrive in the presence of salt) occur when the system is saline, emphasising that Lake Gregory functions principally as a freshwater lake.

Management Issues

Lake Gregory is located within a pastoral lease held for the Mulan Aboriginal Community since 1977. The principal management issue from a conservation viewpoint is the loss of fringing vegetation around the lake that has occurred over the past 50 or more years. Acacia maconochieana, which dies after prolonged inundation, is the most common fringing tree and provides nesting sites for many birds, especially the large colonies of cormorants. Acacia maconochieana trees die during periods of high lake levels but are replaced by seedlings as water levels recede. This provides a mixed belt of live and dead trees around the lake, which is critical to the maintenance of its ecological character. Unrestricted access of cattle to the shore of the lake, and the consequent grazing of seedlings, prevents regeneration of the tree belt. Broad-scale erosion in the catchment with an increased rate of siltation in Lake Gregory may also be a significant issue.

Further Reading

• Halse, S.A. (ed). 1990. The Natural Features of Lake Gregory: a Preliminary Review. Occasional Paper 2/90. Department of Conservation and Land Management, Perth.
• Halse, S.A., Shiel, R.J. and Williams, W.D. 1996. Aquatic Invertebrates of Lake Gregory, North-western Australia, in Relation to Salinity and Ionic Composition. Hydrobiologia (in press).
• Jaensch, R.P. and Vervest, R.M. 1990. Waterbirds at Remote Wetlands in Western Australia, 1986-88. Part One: Lake Argylle and Lake Gregory. Report 32. Royal Australasian Ornithologists Union, Perth.

Case Study 3: New Zealand

Waituna Wetlands Scientific Reserve

By Brian Rance and Wynston Cooper, Department of Conservation, New Zealand

Introduction

Waituna Wetlands comprise an area of approximately 3,556ha situated on the southern coast of the South Island of New Zealand. The wetlands encompass the Waituna Lagoon along with adjacent peatlands, numerous ponds/lakes and coastline forming part of a larger complex of estuaries and lagoons within the Southland area.

Conservation of flora and fauna, and protection of wildlife are the primary uses of the wetland. However, other uses include sport fishing (for Brown Trout Salmo trutta) and game bird shooting. Much of the surrounding area is used for pastoral agriculture.

Major Wetland Types

Within the wetland there are:

Peatlands: this vegetation is governed by the height of the water table and drainage. The most extensive vegetation type is Wire Rush Empodisma minus with Tangle Fern Gleichenia dicarpa, Manuka Leptospermum scoparium and Dracophyllum longifolium. Better drained areas are dominated by Leptospermum scoparium shrublands or Red Tussock Chionochloa rubra (local). Low lying sites are generally dominated by sedges, rush and bryophytes with ponds or pools. One of the special features is a cushion-bog community containing many species adapted to cold, peaty conditions including some species more typically found in montane or subalpine conditions rather than at sea level. The wildlife in the peatlands is not diverse but the area forms the Southland stronghold for Australasian Bittern Botaurus poiciloptilus, South Island Fernbird Megalurus punctata punctata, Spotless Crake Porzana tabuensis and Marsh Crake P. pusilla. All these species have declined elsewhere through habitat loss in Southland.

Waituna Lagoon, ponds and lakes: Due to periodic opening to the sea following the lagoon reaching high water levels, the lagoon is subject to considerable fluctuations in water level. It is a different habitat when open to the sea and thus tidal, from when it is closed and ponded. When open there are extensive tidal mudflats, which form an important summer wader habitat. A large number of wader species (including up to 18 species of trans-equatorial waders) utilize the mudflats. Other waterfowl also utilize Waituna Lagoon as well as the numerous small ponds and lakes. In particular Waituna Lagoon is the principal Black Swan Cygnusatratus site and one of the most important Grey Duck Anas superciliosa sites in Southland. There is a Black Shag Phalacrocorax carbo colony on one of the ponds. The lagoon is a trout fishery of some importance. Several types of vegetation associated with the lagoon edge are present - saltmarsh and allied communities are extremely well developed in southeastern New Zealand.

Gravel coastal beach: This contains a discontinuous vegetation of grasses, herbs and shrubs, most common being Muehlenbeckia axillaris, Gentiana saxosa, and Poa cita.

Streams and waterways: Sea-run Brown Trout are found in the Waituna Lagoon. The streams provide spawning grounds for both the introduced trout and native fish. Populations of Giant Kokopu Galaxias argenteus and Banded Kokopu Galaxias fasciatus, Inanga Galaxias maculatus, Long Finned and Short Finned Eels Anguilla dieffenbachii and A. australis as well as other estuarine and freshwater fish have been recorded.

Major Features of the Waituna Wetlands

Waituna Lagoon was designated a Ramsar site in 1976 since it met three of the four 'Ramsar General Criteria based on plants or animals' for identifying such sites: it supports an appreciable assemblage of endemic and/or threatened species and communities; it has special value for maintaining the genetic and ecological diversity of the region; and it provides a habitat for plants and animals at critical stages of their biological cycles.

Notable endemic taxa include:

Fish:

• Giant Kokopu Galaxias argenteus; National status: vulnerable
• Banded Kokopu Galaxias fasciatus; National status: vulnerable

Birds:

• New Zealand Shoveler Anas rhynchotis variegata; uncommon endemic subspecies
• Variable Oystercatcher Haematopus unicolor; National status: rare
• South Island Pied Oystercatcher Haematopus ostralegus finschi; uncommon endemic subspecies
• South Island Fernbird Megalurus punctata punctata; National status: rare
• New Zealand Dotterel Charadrius obscurus obscurus; National status: endangered (less than 100 individuals remaining)
• Banded Dotterel Charadrius bicinctus bicinctus; National status: vulnerable

Plants:

• Pingao Desmoschoenus spiralis
• Tufted Hair Grass Deschampsia caespitosa var. macrantha, endemic subspecies, National status: vulnerable

Aside from these species of special significance, the area supports a large diversity of birds, native fish, invertebrates and plants. Seventy six species of birds have been recorded, including both international and internal migratory waders. A significant aspect of the migratory wader population is the number of rare species (by New Zealand standards) that have been recorded in the reserve. These include Mongolian Dotterel Charadrius mongolus, Grey Plover Pluvialis squatarola, Marsh Sandpiper Tringa stagnatilis, Sanderling Calidris alba and Asiatic Whimbrel Numenius phaeopus variegalus. The wetlands also serve as an important moulting refuge for the New Zealand Shoveler. Native fish species include several endemic species some of which are rated as vulnerable. Many of the insects and some plants are typically subalpine species. Over 80 species of moth alone have been found in the Awarua Bay/Waituna Wetlands complex and the area is the type locality for a number of species of moth, some of which are not known to occur elsewhere. The diverse flora of the area includes the presence of the interesting cushion bog vegetation and sand ridge plant associations (Pingao, Coastal Tussock and locally uncommon species of mat-daisy).

Current Status

The wetland, which is Crown-owned and managed by the Department of Conservation, was gazetted as a Scientific Reserve in 1983. Entry to the reserve is not restricted, but the relative isolation and difficulty of access ensure minimum disturbance. Monitoring continues on lagoon levels, effects of past fires and the impact of nesting gulls on the cushion bog vegetation. There are also bi-annual wading bird counts undertaken at Waituna Lagoon.

The Wetlands of Ecological and Representative Importance database gives the wetland a ranking of international importance and the wetland was designated a Ramsar site in 1976. The Department of Conservation is investigating the expansion of this Ramsar site to include additional wetland areas.

Major Threats and Management Issues

There are three major threats to the wetland:

• fires - there have been several large fires in adjacent peatlands in recent years;
• in the area surrounding the wetland, an intensification of land use including draining, ploughing and sowing grass influences water quality;
• exotic weed species - Gorse Ulex europaeus, Broom Cytasus scoparius and Spanish Heath Erica lusitanica are found in peripheral areas and are spreading within the wetland.

When the sea outlet from the lagoon is blocked during periods of high rainfall, the water floods back into marginal vegetation. This is a desirable feature for many of the reserve's botanical features which remain because of the occasional flooding of areas and maintenance of a high water table. If this occurs during July-November it can stimulate the breeding activity of Black Swan to a marked degree. However, it can also be detrimental for other species such as waders, as the mudflats used for feeding are not exposed, or for terns, oystercatchers and stilts when the small islands they favour as nesting sites are submerged. Blocking of the inlet also causes drainage problems on some farms close to the lagoon, so a management regime exists whereby periodically the bar is artificially opened to the sea.

Case Study 4: Solomon Islands

The Arnarvon Islands

By Edward Mayer and Susan Brown, Nature Conservancy, Solomon Islands

Arnarvon Islands, A Community-Managed Conservation Area

On 22 August 1995 the first community-managed conservation area in the Solomon Islands officially opened at the Arnarvon Islands. The opening was the culmination of over five years work that included marine turtle surveys, a rapid ecological assessment, extensive community consultations, hiring and training of local conservation officers, and the development of a marine resource biological monitoring programme with completion of the surveys begun before the establishment of the conservation area. The conservation area project at the Arnarvons is a partnership between the Solomon Islands Ministry of Forests, Environment and Conservation (MFEC), The Nature Conservancy (TNC), and the Communities of Kia, Posarae, and Waghena.

An anchialine tidal flat where there is no surface exchange of water - the barrier of sand between the flat and the lagoon is clearly visible. (Photo: Edward Mayer)

The Arnarvon Islands are located in the Manning Straits, midway between Choiseul and Isabel Islands, two large mountainous islands in the Solomon Archipelago. The conservation area comprises approximately 82.7km2 of islands and reef, with a total land area approximately 3km2. The island group consists of three low relief islands, with a diverse mix of shoreline habitat.

Significant areas of tidal flats are found throughout the islands. A number of small completely enclosed tidal flats exist which have no surface exchange with sea water (called anchialine ponds). These ponds fill and drain through tide-driven subterranean movement of water. Several large barachois tidal flats (areas which have surface exchange with the lagoons) occur on all three islands.

Marine and Terrestrial Diversity

The area is recognized as the largest and most important nesting site in the Western Pacific of the threatened Hawksbill Turtle Eretmochelys imbricata (IUCN Red List, 1994). There has been a significant decline in the populations of nesting turtles in recent years. Early surveys, together with anecdotal information from local residents, estimate the population of nesting turtles to be of the order of 500 annually. Recent surveys have shown a decline to less than 100 annually. The reduction in nesting turtles reflects the excessive harvest of Hawksbills for the turtle shell (Bekko) trade with Japan. While the Bekko trade is now prohibited, there is still pressure on the marine turtles because of hunting for domestic consumption of the meat. Concern about this decline led to the establishment of protected status for the islands.

The reef areas surrounding the islands contain at least 43 genera of hard corals and 6 genera of soft corals dispersed over outer fringing reefs exposed to ocean conditions, submerged platform reefs, and sheltered lagoon reefs. This diversity of reef habitat supports numerous species of reef fish in great abundance, including the herbivorous Scarids and Acanthurids, and schools of Giant Humphead Parrot Fish Bolbometopon muricatum, all good indicators of a lack of fishing pressure. In contrast, the sedentary marine resources have experienced a rapid decline due to heavy harvesting pressure. The area, once abundant in Trochus, Blacklip and Goldlip Pearl Oyster Pinctada margaritifera and P. maxima, and approximately 15 species of Béche-de-mer (sea cucumber), is now seriously depleted. The six species of giant clam Tridacna spp. still have a relatively high population density at the Arnarvon Islands despite harvest pressure, making this one of the last places in the Solomons to support a viable population.

One hundred and four species of plants were recorded on the islands during the 1993 rapid ecological assessment, ranging from epiphytic plants to large coastal forest trees. Six different forest types were identified on the islands; Coastal Strand Forest with Casuarina, Pandanus Swamp Forest, Tall Coastal Strand Forest, Swamp Forest predominately Pemphis acidula, Mangrove Swamp Forest, and a small patch of Lowland Rain Forest.

The Arnarvons are a good example of undisturbed low island ecosystems and for their size have a diverse terrestrial fauna. Six species of bats and five species of flying fox (or megachiropteran bats) were recorded on the islands, along with at least seven species of terrestrial reptiles. The islands have significant habitat for seabirds, waders, and migratory bird life, and of the 41 species recorded, there are 12 species of waders and migratory birds, and 6 species of sea birds. Sanford's Eagle Haliaeetus sanfordi, which is rare in the Solomons, is one of the four species of raptors present at the Arnarvons', along with the Brahminy Kite Haliastur indus which is the most commonly observed raptor. The sandy soil provides ideal nesting sites for the Arnarvon's abundant population of the megapode Megapodius eremita. There are several large communal nesting sites on Sikopo Island, which has the highest density of megapodes, while on Kerehikapa and Maleivona islands small nests are scattered throughout. The megapode's egg, as the name suggests, is extremely large for this chicken-sized bird, and has an extraordinarily high yolk to albumen ratio. They are regularly harvested for local consumption.

Community Management Initiatives

Although the islands of the Arnarvon Community Marine Conservation Area (AMCA) are uninhabited, there are a number of communities from Isabel and Choiseul provinces who claim traditional ownership, and are the primary users of the resources. From the beginning of the project, TNC and MFEC have involved these traditional resource owners and users as partners in the planning, establishment, and management of the AMCA.

Within the conservation area, the project works through the community controlled Management Committee, which has drafted a management plan and regulations for the area. This plan is being implemented by community hired Conservation Officers who are responsible to the Management Committee. Activities in the broader area concentrate on building community environmental awareness by focusing on the importance of sustainable levels of harvest, discouraging destructive methods of extraction, and transferring resource management methods learned in the AMCA to the broader area for the protection of resources on a regional level.

The collaborative project is making great strides in the accomplishment of its central objectives: to protect and sustainably manage resources in and around the Arnarvon Islands, and to ensure the viability of one of the world's largest nesting grounds for the threatened Hawksbill Turtle.

Further Reading

• Holtus, P. 1993. Coastal and Marine Habitat Survey: Proposed Arnarvon Protected Area, Solomon Islands. Unpublished report to The Nature Conservancy and Ministry of Natural Resources.
• Leary, T. 1993. Rapid Ecological Survey of the Arnarvon Island. Report to The Nature Conservancy and Ministry of Natural Resources.
• Qusa, M. 1993. Vegetation of the Arnarvon Islands Group (Forestry Division, Ministry of Natural Resources). Unpublished report to The Nature Conservancy and Ministry of Natural Resources.
• Ramohia, P. and Tiroba, G. 1993. The Status of Sedentary Marine Resources in the Arnarvon Group. (Fisheries Division, Ministry of Natural Resources). Unpublished report to the Nature Conservancy and Ministry of Natural Resources.
• Vaughan, P.W. 1981. Marine Turtles: A Review of Their Status and Management in the Solomon Islands. Report to WWF, FSP and Ministry of Natural Resources.

Wetlands - A New Concept

The Ancient Greeks identified four basic elements: earth, air, fire and water. Modern environmental thinking emphasizes the need to take account of traditional knowledge and wisdom, so perhaps this ancient division of the properties of the physical world is an appropriate reminder that wetlands are the meeting places of two fundamental elements, water and earth. As noted by Peter Bacon in the first chapter, the way water and earth meet, the topographic gradient concerned, and the seasonal variations in rainfall or inundation patterns, account for the wide diversity of wetland types. Yet the importance of wetlands, for their intrinsic biodiversity, their productivity and their consequent value to human societies, has only recently been fully recognized. The very word 'wetland' is a recent coinage, not very elegant and difficult to translate, but which aims to sum up this new concept of the fruitful meeting of two elements.

Biological Diversity of Wetlands

The regional overviews illustrate the high levels of biodiversity found in wetlands. After tropical rain forests, they are among the richest ecosystems on this planet. Coral reefs, included in the Ramsar definition of wetlands, contain some of the highest known levels of biodiversity, while other coastal wetlands (including estuaries, seagrass beds and mangroves) are among the most productive. Other wetlands also provide sanctuary for a wide variety of plants, invertebrates, fish, amphibians, reptiles and mammals, as well as millions of waterbirds. Of the world's 20,000 species of fish, approximately 8,500 live in fresh water. While many reptiles are dependent on wetlands for feeding and breeding, virtually all amphibians rely on wetlands for breeding and larval development. Wetlands support many mammals and some species, such as the hippopotamus, are highly specialized for an aquatic lifestyle. The spectacular migrations of some of the waterbirds - which may make a return flight every year from breeding grounds in northern latitudes to wintering grounds in far southern climes - provided the spur for the establishment, 25 years ago, of the Convention on Wetlands (Ramsar, 1971), still the only intergovernmental legal instrument to deal with a single ecosystem type.

The overviews and case studies from Ramsar's seven regions (the Eastern and Western European regions are treated in the same chapter in the present volume) provide many specific examples of this biodiversity. It goes without saying that many other examples might have been chosen, but the 29 presented give a taste of the variety of life to be found in them. Thus the ephemeral wetlands of Northern Namibia can be divided into several habitats, each with its distinguishing biodiversity. The Ebro Delta plays host to many plant species at both their northernmost and southernmost geographical limits, as well as to endemic fish and aquatic birds. The huge diversity of the Belize Barrier Reef is the result of careful partitioning of the reef by all its inhabitants which use it at different times of day or eat differing food. The mangrove habitats of Hinchinbrook Island in Australia are unusually diverse with 27 species of mangrove tree commonly found. The Berbak National Park in Indonesia is thought to be one of the world's most highly diverse areas in terms of palm species. The Berbak National Park in Indonesia is thought to be one of the world's most highly diverse areas in terms of palm species.

It is a sobering thought that the richness of freshwater systems is still poorly known, and that many wetland species, especially invertebrates, have yet to be described. Thus 10% of invertebrates recently sampled in the relatively well-studied Hong Kong Ramsar site of Mai Po Marshes were unknown to science.

Wetland Productivity

In parallel to this support of biodiversity, the introductory chapter by Peter Bacon, the overviews and case studies illustrate the productivity of wetlands. Wetland soils are rich in minerals and other nutrients, and Bacon quotes the example of Lake Naivasha in Kenya where papyrus swamps produced a harvestable standing crop of 30 tonnes per hectare (which furthermore was replaced after harvest in about nine months), compared with only 10 tonnes per hectare from the finest European pastures. Around two thirds of the fish consumed by human beings depend on coastal wetlands at some stage of their life cycle.

Thus there is an overwhelming case for the value of wetlands to human societies. These values may be derived from direct harvesting of fish, from hunting, grazing or agriculture, or through secondary activities like tourism and other human recreational activities; they may equally be provided, almost unrecognized and taken for granted by human societies, through essential functions performed by wetlands, such as control of floods and sedimentation, provision of water (including groundwater recharge), maintenance of water quality and abatement of pollution. These essential goods and services explain why wetlands were often the cradle for the development of human civilizations, like those of the Nile Delta, the Valleys of the Tigris-Euphrates and the Mekong, the fertile floodplains of India and China, or Lake Titicaca; the need to share and organize these wetland benefits was the spur for human beings to coordinate and regulate their activities and their use of natural wetland functions.

The Paradox

Here, in these dual features of wetlands - richness and usefulness - lies the supreme paradox and dilemma, the challenge facing modern day efforts to achieve sustainable development. On the one hand is the extraordinary wealth and variety of living forms and physical properties that exist in wetlands, so bountiful that it seems impossible they should ever be exhausted; on the other the deplorable fact that human use (or rather overuse) has in many cases been excessive, either because the desire for short term profit is destroying the basic wetland resource or the demands of a burgeoning population lead to its over-exploitation. How is this vast richness to be harvested wisely, in a way that will ensure it remains available to future generations?

While some wetlands are testimony to the positive effects of wise use of natural resources (e.g. the Bangladesh Sundarbans, a case study in the Asian chapter), to a large extent the overviews and case studies present abundant illustrations of the multiplicity of threats to wetlands: drainage for agriculture (often with subsequent salinization of soils); organic pollution from fertilizers or pesticides (e.g. in the English Norfolk Broads, Mai Po in Hong Kong and Tasek Bera in Malaysia); urban development, interruption of water flow notably by dams (e.g. at Djoudj in Senegal and Kelbia in Tunisia, or the Yaciretá Dam on the River Parana between Argentina and Paraguay); industrialization, overuse of groundwater (e.g. at Azraq); excessive tourist and visitor pressure.

Because of their own special features, coral reefs are vulnerable to a series of threats: sedimentation; agricultural run-off; coastal development; tourism; and overfishing. It is estimated that these threats have seriously degraded 10% of the earth's coral reefs and currently threaten many more .

One of the greatest threats to biodiversity is the introduction of alien species, whether plants (like Water Lettuce in Djoudj); or fish (such as the Nile Perch and a species of tilapia which have caused a steep decline in the former highly diverse endemic fish fauna of Lake Victoria); or mammals which have been introduced in remote Tierra del Fuego where they and alien fish are a major threat to the few native species adapted to the harsh local conditions.

Human population growth and extension clearly have a massive impact on wetlands, sometimes to the point of destroying them completely. In north and west Europe, "the concentration of economic wealth and highly developed industrialization has seen the greatest loss, degradation and fragmentation of wetlands". The Namibian case study comments that population growth, as in many other African countries, is the single most important threat to the wetland. The Colombian Amazon is the homeland for indian tribes whose traditions were based on a reasonable understanding of the wetlands, so that their impact was almost negligible, whereas the pressure from a growing population of settlers from different regions might be a threat for the wetland ecosystems of the Amazon. In many countries, the need for water - whether for human consumption, agriculture, industry or tourist development - leads to major water supply projects based on construction of large dams and canals. Quite apart from their social impact on human populations downstream or upstream of the constructions, which may force long established settlements to be abandoned, these constructions have huge impacts on the functioning of the wetlands concerned. It has been said many times that water will be one of the major strategic resources of the 21st century. Until now, water supply projects have rarely taken account of wetland values and functions; there is a need in the future for water supply and wetland conservation to be effectively coordinated.

While these factors may threaten the very existence of some wetlands, at a more insidious level they threaten the biodiversity held within them: the frequent references to globally threatened species within the regional chapters is evidence of the scale of this problem.

Broader environmental factors, such as global climate change or desertification, also affect wetlands. Scientific evidence now clearly points to increasingly rapid changes in climate; Lake Chad was much larger 3,000 years ago, but if current predictions come to fruition, there will in the next 50 years be more extreme climatic events, more storms, droughts, floods. How will this affect current measures for wetland conservation? If climatic bands change, the protected wetlands could prove to be in the wrong place; risks of flooding or of desiccation and desertification, aided and abetted by unwise human use, could occur in quite new, unexpected areas.

What Future Action?

This dilemma of the conservation and wise use of wetlands illustrates in a microcosm the environmental problems posed to the world at the threshold of the 21st century. How is the wealth of the earth's many ecosystems to be conserved because of their intrinsic value, and yet be harvested wisely? Wetlands can provide a blueprint and a model for activities in other fields.

The Ramsar Convention, which has now been in existence for 25 years, and has accumulated considerable experience, fortunately offers some pointers to the way forward. The Convention takes as its starting point that international cooperation is necessary for the conservation and wise use of wetlands. So far 93 states are members, and it is clearly essential to ensure that all states become Contracting Parties; the 1997-2002 Strategic Plan therefore calls for universal membership and lays special stress on recruitment from the Caribbean, Near East, Southern Africa and the Pacific. In terms of substantive obligations, the Convention's two basic requirements - designation of wetlands for the List of Wetlands of International Importance, and application of the wise use principle - fit with the call, almost a cliché nowadays, to 'think globally and act locally'. The most important wetland sites, the 'crown jewels', should be designated for the Ramsar List, but not merely designated on paper, they must be managed and conserved (the Strategic Plan calls for all Ramsar sites to have their own management plan, and for 50% of these plans to be in place by 2002). 'Wise use' means taking a broader view at national level of all the factors impacting wetlands; hence Ramsar Contracting Parties should develop National Wetland Policies, or include wetlands in appropriate sections of other national planning instruments relating to natural resources and the environment, so that wetlands are given full recognition in the national procedures for water and land use planning, and so that appropriate structures and legislation are established.

To ensure full application of these two fundamental obligations, other actions, both theoretical and practical, are necessary:

(a) Need for a holistic overview

Since the holistic recognition of the importance of wetlands is so recent, there is as yet only a dim understanding of the global scale and size of the wetland resource. The Asian overview refers to regional wetland surveys of South and East Asia and the Middle East, which identify the major wetland sites in those areas. Similar surveys of internationally important wetlands exist for other regions, while many states have carried out a national wetland survey; thus the North American overview notes that Canada holds 24% of the world's wetlands, an area covering 1.27 million square kilometres. The full area of wetlands in the world is still, however, a matter of some dispute: the World Conservation Monitoring Centre has proposed an estimate of about 5.7 million square kilometres, roughly 6% of the world's land surface. UNEP reports that 47% of the land area of the world (excluding Antarctica) falls within international water basins shared by two or more countries.

(b) Need to establish rates of wetland loss

Once there is a better idea of the overall extent of the wetland resource, and of the size of the challenge facing its managers, the figures need to be put into a world and a historical context. How many wetlands need to be given protected status through national or international conservation measures? There is as yet no clear vision of how many sites need to be protected at national or international level.

The extent of the threats needs to be defined. How does the present extent of wetlands compare with the situation in the past? There are estimates of the amount of certain types of wetland lost in certain countries: the North American overview states that, in the conterminous USA, only 47% of the original wetland coverage remains, though most of Alaska's wetlands remain undisturbed; the Asian overview notes that 85% of the wetlands in South and East Asia are threatened in some way and 50% are severely threatened. Yet there is no full understanding of the overall rate of wetland loss; it has certainly increased dramatically in the last 50 years, and more than half of the world's wetlands have been destroyed this century.

(c) Need to respect regional variation

How are solutions to be adapted to regional differences? In South America, Alaska, Africa and Eastern Europe, wetlands remain relatively untransformed, though the African section warns of the increasing impact of human population growth. In Western Europe there have been grave changes in the extent and functioning of wetlands, and in Central America, the Caribbean and USA too, major changes have come about. In the regions which have suffered major loss, wetland restoration will be a much greater priority, given that it is always much more difficult (if not impossible), and certainly more expensive, to restore lost wetlands than to conserve existing ones.

(d) Action at local, national and international level

Action for conservation and wise use of wetlands must quite clearly be taken at all levels - local, national and international. At local level, there is a need to involve and inform local communities, to ensure that they are aware of the values and functions of the wetlands in their immediate area, and that they are fully concerned in the management and use of such wetlands. Two of the case studies indicate how this might happen: in the Pacific Arnarvon Islands and Old Crow Flats in northern Canada, local communities have played a leading role in making and applying management plans for wetlands, effectively identifying these communities as custodians of wetland biodiversity. As noted in the North American overview, "it is apparent that the cumulative impact of many small individual actions (no single one of which is alarming) is becoming a major threat to the integrity of wetland landscapes". Such issues can only be tackled at local level by a community well aware of the impact of its actions, and this implies enormously increased efforts at creating public awareness, in many cases through the educational activities of non-governmental organizations (NGOs).

Action to implement the two major obligations under the Ramsar Convention, designation of internationally important sites and establishment of wise use policies, can only be undertaken by national governments at national level. Furthermore, the establishment of National Wetland or Ramsar Committees, as recommended in the Strategic Plan, may help to promote a bottom-up management structure and application of the principles of wetland conservation. While these tasks are a matter for the national authorities in each country, national and international NGOs - and of course the Ramsar Bureau - can provide support and assistance in reaching these goals.

The need for international cooperation is graphically illustrated by UNEP's figure of 47% of the world's land area occurring in international water basins. International conventions must work together more closely, so as to achieve synergy, and not duplication, between their operations. This will require not only better coordination between convention secretariats, including joint programming and exchanges between subsidiary bodies such as scientific councils; it will also require a unified approach to the conventions at national level, with greater consultation between national focal points and coordinated reporting to the different conventions. There is a need to ensure integrated application at national level, so that conventions are treated as a complete and effective arsenal of measures for environmental conservation and not as a series of unrelated instruments. Above all, there is a need, in the case of Contracting Parties which are developing countries or in transition, to ensure that funding is available for the execution of obligations accepted under international conventions.

In addition to the general need for cooperation between international conventions, specific cooperation on wetland issues must be promoted. Ramsar needs to work with the Framework Convention on Climate Change to assess the effect of climate change on wetlands; with the Convention to Combat Desertification (since loss of wetlands is after all what often leads to desertification), and with the Convention on Migratory Species, to guarantee that adequate wetland habitat is conserved for migratory waterfowl, fish and other migratory wetland species.

Above all, Ramsar needs to coordinate its action with the Convention on Biological Diversity (CBD). After 25 years, Ramsar brings with it a wealth of tried and tested technical mechanisms and experience, while the Ramsar Strategic Plan defines a series of concrete actions designed to achieve conservation and wise use of wetland biodiversity worldwide. Wetlands could be seen as a microcosm of the application of the CBD. The second chapter presents the many common points between the general provisions of the CBD and the requirements specific to wetlands under Ramsar; it is clear that there are many areas where joint action could profitably be undertaken. The application of the Ramsar principles of listed sites (as the crown jewels of wetland biodiversity) and wise use (as the means of controlling exploitation of these natural resources so that their use is sustainable) could serve as an example and a test case for conservation and wise use of natural resources in other biomes and ecosystems. To achieve this aim, the Ramsar Bureau and the Secretariat of the Convention on Biological Diversity have signed a Memorandum of Cooperation, and the Third Conference of the Contracting Parties to the CBD has included wetlands on its agenda, using a specially commissioned report. The basis for cooperation between the two conventions is therefore well in place.

Wetlands and tropical rain forests are generally considered to be the most threatened ecosystems on our planet. As wetlands continue to be degraded and destroyed, Ramsar will be increasing its efforts to work in collaboration with other conventions, with national and local governments, and with NGOs, to meet the challenges of the next century and ensure that wetland biodiversity is conserved in perpetuity for the use and enjoyment of future generations.

Yassin Al-Zhou'bi, Azraq Oasis Conservation Project, P.O. Box 910994, Amman - 11191, Jordan

Fethi Ayache, Ministère de l'Environnement et de l'Aménagement du Territoire, 32 Rue de la Monnaie, 1001 Tunis, Tunisia

Peter Bacon, Professor of Zoology, The University of the West Indies, St Augustine, Trinidad and Tobago

Demba Baldé, Socio-economist, IUCN-World Conservation Union, P.O. Box 3215, Dakar, Senegal

Ugis Bergmanis, State Nature Reserve Teici, Aivoeksyes -3, Laudona, LV-4862, Latvia

Arvinder S. Brar, Deputy Conservator of Forests, Van Bhawan, Jaipur, India

Susan Brown, The Nature Conservancy, Palu Field Office, Jalan Towua No. 94, Palu, Sulawesi Tengah, Indonesia

Montserrat Carbonell, Technical Officer for the Neotropics, Ramsar Bureau, Rue Mauverney 28, 1196 Gland, Switzerland

Sandra Caziani, Facultad de Ciencias Naturales, Universidad Nacional de Salta, 177 Buenos Aires, Salta 4400, Argentina

Mauricio Cervantes, Wetlands International Mexican Programme, ITESM-Guaymas, A.P. 484 Guaymas, Sonora, México 85400

Kelin Chen, Department of Conservation, Ministry of Forestry, Hepingli, Beijing, P.R. China 100714

Gilberto Cintrón, U.S. Fish and Wildlife Service, Department of the Interior, 4401 N. Fairfax Drive, Arlington, Virginia 22203, United States of America

Wynston Cooper, Department of Conservation, Southland Conservancy, State Insurance Building, 33 Don Street, P.O. Box 743, Invercargill, New Zealand

G. I. Cowan, Department of Environmental Affairs and Tourism, Private Bag X447, Pretoria 0001, South Africa

Kenneth W. Cox, North American Wetlands Conservation Council, Suite 200, 175 Courtwood Crescent, Ottawa, Ontario K2C 2B5, Canada

Roy G. Darville, Caddo Lake Institute, P.O.Box 2710, Aspen, Colorado 81612, United States of America

Rebecca D'Cruz, Programme Officer, Wetlands International - Asia Pacific, Institute of Advanced Studies, Universiti Malaya, 59100 Kuala Lumpur, Malaysia

Gerald Dick, World Wide Fund for Nature, Ottakringer Strasse 114-116, A-1162 Wien, Postfach 1, Austria

Joanna Ellison, Australian Institute of Marine Science, PMB No. 3, Townsville, Queensland 4810, Australia

Ghaith Hamdi Fariz, Manager, Azraq Oasis Conservation Project, P.O. Box 1165, Amman, Jordan

Francesc Giró, c/ Riu d l'Or, 27 3-1, 08034 Barcelona, Spain

Mike Griffin, Ministry of Environment and Tourism, Directorate of Resource Management, Schubert Haus Research Institute, Private Bag 13306, Windhoek, Namibia

Stuart Halse, Department of Conservation and Land Management, Wildlife Research Centre, P.O. Box 51, Wanneroo, WA 6065 Australia

Jim Hawkings, Canadian Wildlife Service, Box 6010, Whitehorse, Yukon Y1A 5L7, Canada

Zakir Hussain, IUCN - World Conservation Union, 302 Outreach Building, AIT, G.P.O. Box 2754, Bangkok 10501, Thailand

Roger Jaensch, Wetlands International Oceania Program, c/o Wetlands and Migratory Wildlife Unit, Australian Nature Conservation Agency, GPO Box 636, Canberra ACT 2601, Australia

Tim Jones, Technical Officer for Europe, Ramsar Bureau, Rue Mauverney 28, 1196 Gland, Switzerland

Tom Kabii, Technical Officer for Africa, Ramsar Bureau, Rue Mauverney 28, 1196 Gland, Switzerland

Holger Kolberg, Ministry of Environment and Tourism, Directorate of Resource Management, Schubert Haus Research Institute, Private Bag 13306, Windhoek, Namibia

Jane Madgwick, Chief Conservation Officer, Broads Authority, Thomas Harvey House, 18 Colegate, Norwich, Norfolk NR3 1BQ, United Kingdom

Paul Mafabi, Project Manager, National Wetlands Conservation and Management Programme, Department of Environment, Ministry of Natural Resources, 10th Floor Post Office Building, P.O. Box 9629, Kampala, Uganda

Edward Mayer, The Nature Conservancy, Palu Field Office, Jalan Towua No. 94, Palu, Sulawesi Tengah, Indonesia

Michael McCoy, Programa Regional en Manejo de Vida Silvestre, Apdo. 1350, Universidad Nacional, Heredia, Costa Rica

Luis Germán Naranjo, Departmento de Biologia, Universidad del Valle, AA 25360, Cali, Colombia

Faizal Parish, Executive Director, Wetlands International -Asia Pacific, Institute of Advanced Studies, Universiti Malaya, 59100 Kuala Lumpur, Malaysia

Brian Rance, Department of Conservation, Southland Conservancy, State Insurance Building, 33 Don Street, P.O. Box 743, Invercargill, New Zealand

Saskatchewan Wetland Conservation Corporation, Room 202, 2050 Cornwall Street, Regina, SK, Canada S4P 2K5

Roberto P. Schlatter, Director, Instituto de Zoologia 'Ernst F. Kilian', Facultad de Ciencias, Universidad Austral de Chile, Valdivia, Chile

Dwight Shellman, Caddo Lake Institute, P.O. Box 2710, Aspen, Colorado 81612, United States of America

Hisashi Shinsho, Kushiro City Museum, 1 - 7 Shunkodai, Kushiro, Hokkaido 085, Japan

Rob Simmons, Ministry of Environment and Tourism, Directorate of Resource Management, Schubert Haus Research Institute, Private Bag 13306, Windhoek, Namibia

Seydina Issa Sylla, Directeur des Parcs Nationaux, B.P. 5135 Dakar-Fann, Senegal

Albert Martinez Vilalta, Parc Natural del Delta de l'Ebre, Pça. 20 de maig 2, 43580-Deltebre, Spain

Sue Wells, 56 Oxford Road, Cambridge CB4 3PW, United Kingdom

Chenggao Yan, Department of Conservation, Ministry of Forestry, Hepingli, Beijing, P. R. China 100714

Lew Young, World Wide Fund for Nature Hong Kong, G.P.O. Box 12721, No. 1 Tramway Path Central, Hong Kong\