Ducks, Geese and Swans of India (Their Status and Distribution)

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About the Author

Dr. Asad R. Rahmani is the Director of the Bombay Natural History Society since 1997. He joined BNHS in 1980 and worked as Principal Scientist in various projects. In 1991, he joined the Department of Wildlife Sciences, Aligarh Muslim University, where he worked for six years. In 1997, he rejoined BNHS as Director. He has written more than 100 peer-reviewed research papers in national and international journals, five books and numerous popular articles and book reviews. He is the Executive Editor of the IBNHS, and Editor of Hornbill and Mistnet. He has been a Ph.D. guide to eight students, and principal investigator of many prestigious projects of the BNHS, including till' Important Bird Area (IBA) Programme of Birdlife International and BNHS.

M. Zafar-ullslam worked with the Bombay Natural History Society from 1993 to 2006 in several research projects, including Grassland Ecology Project, Important Bird Areas (IBA), Biodiversity Conservation Prioritization Project, and Anatidae Atlas. He also developed many conservation projects for BNHS that included Darwin-funded conservation training programme for IBCN members in India. In collaboration with the RSPB-Bird life International, he had successfully established the Indian Bird Conservation Network (IBCN). As Manager of IBA and I BCN, he started Mistnet. He has co-authored seven books including Important Bird Areas in India, and Potential and Existing Ramsar Sites of India, and the present one. He has also published several research papers and articles. Presently, he is working as Research and Field Monitoring Manager (Reintroduction Programmes) with the National Wildlife Research Centre, Taif, Saudi Arabia.

Preface

It is a well-known maxim that in the modem world 'knowledge is power'. To be better conservationists, we need the 'power' of good knowledge of species, habitats, ecosystems and the socio-political pressures on environment. We also need good knowledge to bring conservation issues in the mainstream agenda of the human society. Our book Ducks, Geese and Swans of India: Their Status and Distribution, is a small attempt in this direction. We have tried to bring all the available information on Indian Anatidae species in one document. We have also highlighted information gaps, particularly through maps. In some sections, the book is 'heavy' to read, repetitive and boring, but nevertheless useful to serious researchers and decision makers. The main purpose of the book is to disseminate the available information and to stimulate collection of better information not only on the species mentioned in the book, but on all Indian bird species.

As most of the conservation action takes place at the state level in India, we have given state-wise species distribution. We have depended heavily on published information, however, some unpublished, but verifiable information, is also used. Since 1987, India is participating in the Asian Waterbird Count (AWC), but the data are not fully authentic and verifiable. We have included data only from 1997 to 2005 when the AWC was conducted under our supervision. Even then, we have included only that data which we could authenticate from the State Coordinators of the Awe. We have excluded all unreliable records, particularly if they were out of range of the species or the numbers were too large and therefore doubtful. We have also excluded some doubtful published records. For all site and number records, we have given the reference, except in those cases where we have cited our own records. As the AWC records are huge, we have posted the data on the BNHS web page and also given in a CD, along with ringing recovery records. We encourage readers to visit the web and go through the CD.

This book will show that there is huge data deficiency for some species, sites and regions. There is a need to collect more information on species' distribution, within and outside India. We need to learn more about the movement patterns of Anatidae species, particularly migratory ones. As the ringing and recovery maps will prove, there are many gaps in our knowledge of migratory movement of birds from China (at the time of two major bird ringing projects in 1960s and 1980s, there was very little contact with China so we do not have recovery information from this country). Now the political situation has changed so we need to start long-term and wide-spread bird ringing projects in India, China, Russia and all other Central Asian flyway countries. This is particularly important due to the avian flu scare.

Birds are some of the best indicators of the environment. With the looming dangers of climate change and massive destruction of wetlands, we need to monitor bird populations to take effective conservation measures to save them. We need to start monitoring populations of ducks and geese (wild swans are no longer reported in India), and later we can extend this monitoring scheme to all species. We also need to develop distribution and breeding atlases of Indian birds. But, most important is to make good field data available under bird monitoring schemes.

We will be happy if our book stimulates the Government of India, ornithologists, birdwatchers and conservation NGOs to develop a large-scale and long-term bird monitoring scheme. Perhaps, the embarrassing gaps in the distribution maps of some species, as shown in this book, will be filled up some day.

Introduction

Among different groups of fauna, birds are the most favoured group. And, among birds, ducks, geese and swans are extremely popular with the general public, mainly because of their elegance, bright plumage, aura of migration, and habitat in which they live. Unfortunately, many species of ducks, geese and swans (Anatidae) are threatened with extinction due to human-related factors. Various conservation measures have been taken to save them but to be more effective, we have to properly know their distribution at regional and global levels.

Developing distribution maps helps in identifying important conservation areas. During the course of migrations, most long-distance migrants need to break their journey, often at several points, to renew their fat and protein reserves. These stop-over sites, where abundant food is available are crucial habitats for the Anatidae species. Some species use only a very small number of sites, probably because of their highly specialized feeding and habitat requirements. These sites may be extremely important, for it seems that in many cases no other suitable staging areas are available. Thus, the loss or degradation of even one of these sites could have serious consequences for the species concerned (Scott and Rose, 1996).

India has an age-old tradition of nature conservation which is reflected not only in old literature and cultural ethos, but also in its constitution, policies, legislation and organizations. Sacred groves are scattered all over the country, and have found expression in every culture and religion. Abharanyas (forests without fear) were established by many Indian kings, where hunting of animals was prohibited. Almost all large temples have sacred groves, sacred trees (generally Ficus spp.) and tanks where all types of hunting are banned. Many rulers had also established sanctuaries, but these were mainly for hunting purposes. Nonetheless, they protected large tracts of natural habitats. After India's Independence, and the merger of semi-autonomous states with the Indian Union, many of these former hunting grounds were established as sanctuaries. The most famous are the Ranthambore National Park and Keoladeo National Park in Rajasthan, and the Bandavgarh National Park in Madhya Pradesh.

For a long time, only two types of protected areas were recognized in India: national parks and sanctuaries. Other categories include tiger reserves, biosphere reserves, reserved forests, social forestry areas and village forests. In the recently amended Wildlife (Protection) Act, two new categories of protected areas have been added: Community Reserves and Conservation Reserves. The main criterion that distinguishes these two categories is land ownership. If the land ownership is private or with the community, then the community reserve category is applicable, and if the land ownership is with the government, then the area could be declared as a conservation reserve. The ground reality is that many community based conservation happens on government lands, such as reserve forest, wetlands, and coasts. A good example is the nesting sites of the Vulnerable Spot- billed Pelican (Islam and Rahmani, 2004).

A significant proportion of birds (and other animal and plant) species can be effectively conserved by the protection of key sites, either as officially protected areas (national parks, wildlife sanctuaries, community reserve, or conservation reserve), or through the promotion of sustainable land-use practices.

A network of wetland sites which are protected areas exist in India, but there are many more sites which qualify the Ramsar criteria (Islam & Rahmani 2008), and were identified as !BAs based on international criteria (Islam & Rahmani 2004). Emphasis should be given to protect them for the long-term conservation of species of Anatidae and other groups of birds.

To ensure the continued survival of common species, and reversal of population decline of threatened Anatidae species, we have to develop conservation plans. Habitat protection is perhaps the best guarantee for the long-term survival of most species. The Wetland Conservation Programme of the Ministry of Environment, Government of India has identified 94 wetlands of national importance (Islam and Rahmani 2008). This list has now been increased to 103 wetlands (Sidharth Kaul, pers. comm., 2008). The Government of India has also identified 25 wetlands as Ramsar Sites, but looking at the diversity and spread of Indian wetlands, we need more Ramsar sites. Islam and Rahmani (2008) have listed 135 more sites which fulfils the Ramsar Criteria. During the A WC, hundreds of wetland sites have been identified by participants in India but the data are temporarily and spatially limited (see Perrennou et al., 1994, Li and Mundkur 2004, 2007) with limited use for conservation planning. What we need in India is systematic data collection on the distribution and abundance of Anatidae (and other waterbirds), and also the status of wetlands. We need to develop a proper long-term, waterbird monitoring system. Only then we will be able to get an idea of the numbers and population trends of various species.

Looking at the threats of climate change and spread of new avian diseases, it is necessary to know the distribution, population concentrations, movement, and population trends of various species of ducks and geese. Some work on wild bird monitoring and avian flu surveillance has been done in India (Rafunani et al., 2008) but we require a much more concerted and widespread effort to check the spread of avian flu (and other diseases) from wild birds to domestic birds and vice versa.

Ducks, geese and swans, collectively known as waterfowl, are a well-recognized and well-studied group. They are the common hosts for (LPAI) Low Pathogenic Avian Influenza viruses, the only bird group in which the viruses have been found throughout the year in wild populations (FAO 2007). Waterfowl made up the vast majority of wild birds infected during the H5N1 AI mass mortality event in China in 2005/2006 and they were also the prevalent group of wild bird species infected during numerous mortality events as the virus spread from east Asia in to west Asia and Europe (FAO 2007).

It is impossible to predict which influenza strain will be the next pandemic virus. One possible candidate is the avian H5N1 strain which has become endemic in wild waterfowl and in domestic poultry in many parts of Southeast Asia, and is recently spreading across Asia, Europe and Africa. H5N1, a highly pathogenic avian influenza strain, caused multiple outbreaks in poultry on three continents and has infected nearly 380 persons, killing more than half of them.

Avian influenza is widely prevalent in all avian species, but the wild birds are recognized as source and reservoir for all subtypes of avian influenza virus (AIV), but the complex interaction among these diverse host and virus populations is still not fully understood (Stallknecht and Brown 2007). A general concept of AIV epidemiology in wild birds exists; however, the presence of highly pathogenic avian influenza (HPAI) H5Nl viruses in wild birds has reinforced the need for a much more detailed research on AIV natural history. Worldwide, the wild avian reservoirs for AIV are incompletely defined, even within well-studied groups such as the Anseriformes and Charadriiformes. This lack of clarity applies not only to avian host species, but also to the various subtypes of AIV present within these populations

Most of the earlier researches clearly demonstrate that species and population structure are important in AIV maintenance, transmission, and possibly long- distance movement (Stallknecht and Brown 2007, FAO 2007, 2008). Species-related differences to general behaviour, spatial and temporal distribution, habitat utilisation, migration behaviour, population age structure, and individual species susceptibility all potentially influences a species' role in AN epidemiology (FAO 2008, WHO·2008). So, these roles must be clearly defined if we are going to understand the full implications of current HP AI H5Nl virus introduction into the wild bird populations and most importantly to prevent the next outbreak (Stallknecht and Brown 2007).

Most water bird populations breeding in central Asia are migratory; with migratory routes occurring as loosely organized flyways (where many species follow similar migratory paths). A flyway Can be defined as "the entire range of a migratory bird species (or groups or related species or distinct populations of a single species) through which it moves on an annual basis from the breeding grounds to the non-breeding areas, including intermediate resting and feeding places as well as the area within which the birds migrate". Breeding populations in central Asia may migrate southwest in to southern Asia (Central Asian Flyway) or to East and Southeast Asia and Australasia (East-Asian-Australasian Flyway) or Southern Europe (Black sea/Mediterranean Flyway) or Eastern Africa (West Asia-East Africa Flyway). They may also mix with birds that travel along the Central Pacific Flyway (those breeding in East Asia and migrating south to the Pacific Islands and Australasia), and in the East Atlantic Flyway (which breed in Northern Asia and spend the non-breeding period in Western Europe and Western Africa). Migratory, aquatic birds are therefore perceived by some as potential threat to animal and human health, as they carry several infectious agents, which they may spread along their migratory pathways (FAO 2007).

Health monitoring and surveillance of wild birds is very important. The importance of improving monitoring of diseases in wild birds has been widely recognized by international agencies, such as FAO and WHO. The Central Asian Flyway Action Plan for the Conservation of Migratory Waterbirds and their Habitats, as finalized and endorsed by range states of the Central Asian Flyway, at their second meeting in New Delhi, has called for action that Range States shall monitor disease occurrence in wild waterbirds and using a multi-disciplinary approach, to assess disease risk and implications for human health, in relation to poultry husbandry and trade practices, trade in wild water birds, and migratory water bird movements.

The role of migratory birds in transmission of highly pathogenic avian influenza virus H5N1 is still unclear, but studies confirmed that aquatic bird species of the world are the predominant natural reservoirs of influenza viruses (Webster et al., 2007, see FAO 2007). It was also noted that the Asian H5N1 virus is in rapid evolution, it has already acquired the geographical and host range to make it a pandemic threat in poultry and the potential exists for this virus to acquire consistent human-to-human transmissibility and cause a human pandemic (Webster et al., 2007).

It is necessary to have a thorough surveillance and monitoring of wintering migratory species in the susceptible regions of South-east Asia, including India. Regular monitoring and surveillance provides information on the health status of birds that may appear clinically free from the disease. Moreover, this should be a regular procedure in all disease affected and disease prone countries at least for some years to come. Monitoring and surveillance is also increasingly being recognized as a useful, often essential, prerequisite for early detection and diagnosis of any incidence of HPAI (FAO 2007, 2008, WHO 2008).

Although in India, nearly 700 wild birds sampled during 2006-2008 were all found negative for HPAI H5Nl (Rahmani et al., 2008), in other parts of the world, birds with affinities for wetland habitats make up nearly 60 percent of the wild bird species infected with the H5Nl virus and also account for the greater proportion of wildlife mortalities (FAO 2007). Therefore, it is important to study the distribution, movement and pattern of migration of all water- dependent birds, particularly wildfowl. This book is a small attempt in this direction.

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