African-Eurasian Flyways: current knowledge, status, and future challenges
Global Flyways Conference 2004
A global review of the conservation, management and research of the world's major flyways
3-8 April 2004, Edinburgh, UK
Abstract for Plenary presentation, 4 April 2004
African-Eurasian Flyways: current knowledge, status, and future challenges
Nick Davidson & David Stroud
Addresses: Nick Davidson, Ramsar Convention Secretariat, Rue Mauverney 28, 1196 Gland, Switzerland. Email: email@example.com; tel. +41 22 999 0171; fax +41 22 999 0169. David Stroud, JNCC, Monkstone House, City Road, Peterborough PE1 1JY, UK. Email: David.Stroud@jncc.gov.uk
Waterbird populations depending on flyway site networks in Africa-Eurasia are amongst the most well-studied of any animals in the world. Numbers, distributions and status have been extensively monitored and researched for the last 40 years, yielding a wealth of knowledge and understanding of migration movements and phenology, and leading the way in unraveling of the complexities of the ecophysiology of long-distance migrations. The importance of maintaining the ecological character of the network of wetlands, both inland and coastal, on which these populations depend was the driving force behind the establishment in 1971 of the Ramsar Convention on Wetlands (the full name of which indicates "Wetlands of International Importance, especially as waterfowl habitat"), the oldest of the global multilateral environmental agreements (MEAs). More recently these flyways have become the focus of a further MEA, the Agreement on the Conservation of African-Eusasian Migratory Waterbirds (AEWA) developed under the aegis of the Convention on Migratory Species (CMS). In the AEWA region, 92 countries are now Parties to the Ramsar Convention, and since 1999 AEWA has entered into force in 44 countries.
This paper provides a brief overview of waterbird populations in Africa-Eurasia, drawing on examples from studies particularly on waders (shorebirds) and Anatidae (ducks, geese and swans), will assess their current conservation status, the value of using waterbirds as indicators of global change, and whether the transfer of scientific research knowledge to policy-relevant application of conservation measures has been effective. Future challenges are outlined, particularly as to how and if waterbird science remains relevant to the key priority issues of securing biodiversity conservation in the context of sustainable development, food and water security and poverty eradication which, as set out by the World Summit on Sustainable Development (Johannesburg, 2002), are the focus of attention in the developing world, and especially Africa.
In the waterbird families covered by Waterbird Population Estimates 3rd edition (WPE3) there are at least 762 biogeographic populations (including 14 extinct or probably extinct populations) of 307 species occurring in Africa-Eurasia, some 35% of the global total. 46% are resident (or short-distance dispersers/migrants) and 54% are migratory. 20% of resident populations are restricted to African islands and many of these are small, declining and/or threatened populations. WPE3 lists 346 populations in Europe and 611 in Africa (but note that some populations occur on both continents). AEWA covers 497 populations of 221 migratory waterbird species in 23 families, but certain migratory species of waterbird families which are not wetland-dependent are excluded, as are resident wetland-dependent species. For migratory species, waders (28.9% by species) and Anatidae (21.7%) dominate the flyways.
Flyways are different for different taxa. For example, for waders three main flyways have been defined covering the region (East Atlantic, Black Sea/Mediterranean, and West Asian/East African). But for many Anatidae species, population segregation is less clear, fewer reach south into Africa, and more move on a north-east - south-west Eurasian axis between breeding and wintering areas. However, populations of geese and swans tend to have highly discrete flyways and segregated populations which use traditional breeding and non-breeding ranges.
Overall knowledge of populations is better in this region than for flyways in other parts of the world. WPE3 provides a population size estimate for 91% of populations using Africa and 97% in Europe (for other regions, figures range from 59-81%). Population trends are less well known (Africa 63% and Europe 74%, cf 36-64% for other regions). But this masks considerable variation in information quality between flyways within the Africa-Eurasian region - for waders better for East Atlantic coastal populations (93% with trends), than the Black Sea/Mediterranean (76%) and particularly African populations (30%) and those using the West Asia/East Africa flyway (35%).
Two indicators can be used to provide insights into the level of success of conservation efforts to safeguard migratory waterbird populations in this region.
First, a 'process-oriented indicator': progress in the designation of Wetlands of International Importance ('Ramsar Sites'). For waterbirds (using Ramsar Criteria 5 (>20,000 waterbirds) and/or 6 (>1% of a biogeographic population)), in the AEWA region 465 sites (83% of which are in Europe) covering 30.4 million hectares have been designated. This may appear good progress towards the 'coherent and comprehensive national and international networks' of Ramsar sites called for by the Convention's Strategic Framework (Resolution VII.11). But recent analyses by BirdLife International of Important Bird Areas in relation to Ramsar Sites in Europe and Africa found that only 24 % of European IBAs considered to qualify are wholly or partly Ramsar sites, and only 14% of such African IBAs. At least a further 2084 wetlands appear to qualify for Ramsar designation for waterbirds in these regions. Designation activity has also been variable between countries, with a high proportion of the total number of sites having been designated by a small number of Contracting Parties. Furthermore, in 2002 for only 35% of Ramsar sites in Europe and 21% of sites in Africa are there believed to be management planning processes being implemented. There is clearly a long way to go to secure sustainable management of a comprehensive flyway site network for waterbirds in Africa-Eurasia.
In addition, there have been very few analyses of the conservation status of site networks for specific biogeographic populations, yet these analyses should be a key to identifying future site safeguard action priorities, since is it from the level of biogeographic populations that coherent flyway networks for migratory species need to be built. Such analyses are necessary also to highlight strategically important locations whose protection is critical in terms of individual migratory and eco-physiological strategies.
Second, an 'outcome-oriented' indicator: the status of waterbird biogeographic populations in the region. With over 40 years of geographically extensive monitoring of waterbirds in parts of the region, the waterbird community has a dataset which is of unparalleled quality for large-scale biodiversity monitoring. This monitoring information has now become of even more relevance in relation to the global biodiversity target established by the WSSD in 2002, of "significantly reducing the rate of loss of biological diversity" by 2010, and the even more challenging EU target of halting the decline of biodiversity by 2010.
Results are not encouraging. WPE3 reports that, of populations with known trends, 45% are decreasing and only 16% increasing in Africa, with only a slightly better picture for Europe: 39% decreasing and 32% increasing. Recent flyway-scale analyses for African-Eurasian waders (WSG: Cadiz Conclusions 2003) reveal a similar story. The East Atlantic Flyway is in the healthiest state, with only 37% of populations decreasing. 65% are decreasing on the Black Sea/Mediterranean Flyway, and 53% on the West Asian/East African Flyway. Island populations have a particularly poor conservation status. Comparison with wader population trends in the 1980s/90s indicates that more (8 populations) are in long-term decline that are in long-term increase (3 populations).
A preliminary analysis for Anatidae suggests that such declines are widespread across taxa in the region. Overall, 43% of the 121 African-Eurasian populations are decreasing, and only 33% increasing. Swans (25% decreasing, 75% increasing) and migratory geese (23% decreasing, 50% increasing) have a healthier conservation status that migratory ducks (44% decreasing, 31% increasing) and especially non-migratory populations (45% decreasing and only 14% increasing). Similar analyses for migratory species only in other taxa suggest that rails (70% decreasing), cranes (61%) terns (45%) have an even worse status than Anatidae and waders. Only grebes (9%) and gulls (9%) appear to have a relatively 'healthy' status in Africa-Eurasia.
Analyses of the characteristics of populations in decline can help point at likely drivers (sources) of the problem, and should form the basis for conservation policy and action priorities - especially since some potential change drivers are unlikely to be tractable to management responses. For waders, three groups of populations are in particular trouble. First, arid and semi-arid zone breeders in West and Central Asia and the Mediterranean. Second, temperate wet grassland European breeders. Third, certain long-distance non-stop migrants on the East Atlantic Flyway. Here, the extent of dependence on the Wadden Sea as a critical autumn and especially spring staging area is strongly correlated with the extent of decline. Such findings stress the critical importance of maintaining the ecological character of key staging areas for migratory populations - yet many worldwide continue to be destroyed or degraded.
For Anatidae, 25% of the decreasing populations occur in the Black Sea/Mediterranean region, and a further 13% are Madagascan resident populations. Further such analyses are urgently needed to all waterbird taxa. Similarly, more research attention needs to be paid to those populations which are increasing, to establish how and why they have been able to increase whilst others using the same flyways, and breeding, staging and wintering areas are often in rapid decline. In addition, very few broad-scale syntheses at the flyway and/or taxon scale (cf the International Wader Study Group's 2003 Cadiz Conclusions) seem to have been made, yet these form an essential basis to guide effective use of limited conservation resources: we cannot hope to address all the individual conservation issues on a population by population basis - so this broader analytical approach is needed to determine at which habitats, regions, and key sites our resources and conservation actions should be aimed at for maximum effect.
Conservation provision for most highly (globally) threatened waterbirds is also inconsistent. Of 15 migratory waterbird species globally threatened with extinction and listed by AEWA, seven are the subject of international action plans (generally those species occurring in Europe  - with most existing plans have been driven by the European Union and/or the Council of Europe), whilst eight are not (generally those occurring in Africa and the Middle East ). All those species without action plans are still declining, whilst at least some of those with action plans are either stable or increasing in numbers. Lack of international action planning in Africa and the Middle East is a significant issue.
Overall, the conclusion can be drawn that despite the very extensive knowledge on how waterbirds use African-Eurasian flyways, this is not being effectively transferred into action by those responsible for waterbird and wetland conservation implementation, at national policy level and on the ground site-based action. Nor has the conservation effort led to maintaining or restoring the health of many waterbird populations, including those which are globally threatened. Alternatively it might be argued that the situation would otherwise be far worse! Either way, the present evidence suggests that much more needs to be done if the WSSD and EU 2010 biodiversity targets are to be achieved, at least for waterbirds.
Whilst continuing research and continued monitoring and status assessment of migratory waterbirds are valuable and necessary in gaining further understanding of whether the 2010 biodiversity targets are being met, and what further biodiversity conservation action is needed, it is not sufficient only to provide listing of such information. More innovative and focused analyses and better presentation of the messages these convey, in forms suitable for raising public and governmental awareness, is essential to point clearly at what is driving the problems - and what policy and management responses are needed. It is also essential to underpin this with full and free access to key data and information sources, especially WPE3, which are needed to form the basis of innovative analyses.
It is clear that securing the health of waterbird populations can make an important contribution to biodiversity conservation, but it is important to recognize that this can seem largely distant and irrelevant to addressing the pressing issues and current focus of the developing world on the Millennium Development Goals (MDGs) concerning food and water security, sanitation and poverty eradication. This urgent issue for Africa is reflected in the development and implementation of the New Partnership for African Development (NEPAD), which recognizes that the sustainable management of wetlands is a key element of sustainable development in the continent. This conference must debate and set out clearly if, and how, the resources devoted waterbird research and conservation contribute to this imperative.
1. Anser erythropus, Branta ruficollis, Marmaronetta angustirostris, Oxyura leucocephala, Crex crex, Vanellus gregarious and Numenius tenuirostris.
2. Geronticus eremita, Grus leucogeranus, Sarothrura ayresi, Phalacrocorax neglectus, Phalacrocorax nigrogularis, Egretta vinaceigula, Ardeola idea, Grus paradisea and Grus carunculatus.