Bird Migration in Indian Sub-Continent

Summary of Dr R Suresh Kumar’s Talk:

Tracking the migration of species is a fascinating experience and this gets even more exciting when it involves those that literally travel across the globe. With advancements in space-based tracking technology incredible feats of migrating birds are now beginning to be revealed. And one such is the story of Amur Falcon Falco amurensis from Northeast India.

Amur Falcon a small bird of prey, predominantly insectivorous is an autumn passage migrant to northeast India. This was one of the least talked about species until November 2012 when all that changed following reports of a massive large-scale harvest of the falcons, numbering in thousands for consumption at a remote locality in Nagaland. This led to a series of conservation actions there and one such was the satellite tracking of the falcons in November 2013. While the primary aim was to create awareness among local people, it was also an opportunity to better understand their migratory movements and identify stop-over sites in the region, and elsewhere. Thus, between 2013 to 2019 a total of 15 Amur Falcons were satellite tagged from across stop-over sites in Nagaland and Manipur. The tracking effort revealed interesting insights into the Falcon’s incredible journeys and this helped bring about a change in the attitude of local people leading to a complete halt in hunting of the falcons. With millions of Amur Falcons gathering at select sites in Northeast India every year on their autumn migration, some of these sites are now famously known as the “Falcon capital of the World”.

Six of the tagged falcons were tracked for at least one full year, documenting their entire trans-hemispheric migration from northeast India to their grassland non-breeding grounds in the African Veldts and to their summer breeding grounds in the Manchurian Steppe, and back. The falcon’s arrival in their breeding grounds coincided with the onset of northern summer and the same in their non-breeding grounds with the austral summer. The abundant food resources becoming available at these sites during summer is what drives the Amur Falcon’s trans-hemispheric journeys. Uniquely, between northeast India and Somalia, the tagged falcons undertake nonstop flights both on the onward and return migration of more than five days covering a distance of 5500 to 6000 km, and a large part of this includes the Arabian Sea crossing of over 3000 km. These nonstop flights are clearly fueled by tailwinds, and tagged falcons were also observed to take benefit of cyclonic storms confirming the movements of the species to be strongly attuned to monsoon tailwinds.

It is now known that the long-distance trans-hemispheric migration of the Amur Falcons encompasses a journey of close to 20,000 km one way and they pass through 23 countries each year. And, we know why they do this. The incredible journeys of the Amur Falcon not only connect different migratory bird flyways, or connect different landscapes but also connect different local communities (people) and their cultures. In northeast India, Amur Falcons now fly free.

Summary of Ms. Amarjeet Kaur’s Talk:

In developing nations like India, 

the Conservation of wildlife is impossible without the support of local people. Dive deep in and you find Pandora’s box of tips and tricks for effective conservation along with the social development of people living in the vicinity of wildlife. In India, the association of wildlife has always been there in different cultures, religions, and communities, where people revere certain flora and fauna as part of their culture. Go north into the cold climes of the Himalayas where people have some more story to tell, which is rather less explored. Every summer the local people of the hills await the arrival of a summer-breeding visitor to the region, a long-distance migrant, the Barn Swallow! From the westernmost breeding grounds to eastern Himalaya in North Bengal and Sikkim, and then in the north-eastern hills in Imphal, Manipur, people of different cultures, and different belief systems, know Barn Swallows in their local folklore. Here people revere them, refer to them as “god birds” and feel lucky to have them nest in their properties. And it is not just in India that the Barn Swallows are considered auspicious, it is everywhere across their breeding range in the world. Recent studies have shown steep declines in the populations of Barn Swallows where in the last 40 years, 76% of decline has been observed in North America and Canada. Populations are also declining in parts of Europe. However, what is happening with the populations in India is not known due to the lack of any ecological data on the species. Given that the Himalayan Mountain chain is relatively recent and people settling here is also recent, when was it that the Barn Swallows started to come in here? And are all these populations breeding across the 2500 km chain the same? This first study of Barn Swallows in India is looking at the morphological and molecular differences among these populations breeding from Kashmir to Manipur. The study also focuses on understanding the distribution of Barn Swallows across the Himalayan arc and in north-eastern hills and looking at questions like factors deciding the nesting distribution, the role of geophysical characters, local climatic variables, on-nest-site selection, and nesting patterns. One key aspect of this study is also to look closely at the human perception of these birds, and how the cooperation of people is significant in the successful breeding of the swallows nesting in their houses and shops. The last and another important aspect of this study is also to look at the movement and migration patterns of Barn Swallows to and from the breeding grounds and aim to clearly tell the curious people hosting these birds for six months in their properties, the answer to their favourite question “where do these birds actually go in winters”?

Summary of Mr. Rajdeep Mitra’s Talk:

Sea bird migration is a fascinating natural phenomenon observed across the globe. These remarkable birds undertake long and often arduous journeys, traversing vast distances to reach their breeding and wintering grounds. Several factors influence sea bird migrations, including availability of food, changes in daylight and temperature, and breeding requirements.

In India, one of the significant locations where sea birds nest is the Lakshadweep archipelago.

This group of islands in the Arabian Sea provides a vital habitat for various bird species. Among the many islands in Lakshadweep, Pitti Island bird sanctuary stands out as a key nesting site. Here, species like Sooty tern, Brown noddy, Lesser crested tern, and Greater crested tern find suitable conditions to breed and rear their young.

Despite their prominence in these nesting grounds, there is still much to learn about these birds. Questions about their post-breeding destinations, the extent of shared nesting grounds, competition between different species, potential variations in sea bird populations across latitudes remain largely unanswered. How the environmental factors such as monsoon influence the migration behaviour and route selection is another mystery that still remains to be unfolded.

The islands of Lakshadweep face several challenges and threats that impact sea bird populations. Egg collection and guano collection (bird droppings used as fertilizer) have been detrimental to nesting colonies. Moreover, rising sea levels due to climate change pose a significant risk to the fragile island ecosystems that sea birds rely on.

Recognising the need to better understand and conserve these enigmatic birds, the Lakshadweep Forest Department and the Wildlife Institute of India have joined forces. Together, they have initiated a project aimed at unravelling the mysteries of sea bird migration through the use of satellite tagging. This innovative approach will enable researchers to track the movements of individual birds, gather valuable data on their migration patterns, and gain insights into their behaviour and habitat requirements.

Through this collaborative effort, it is hoped that a clearer picture will emerge regarding the remarkable 

journeys undertaken by sea birds, their ecological interactions, and the challenges they face. This knowledge will be instrumental in formulating effective conservation strategies to protect these captivating creatures and the unique ecosystems they inhabit.