Text by Munmita Boruah
Photos by Udayan Borthakur
A large flock of winter migratory waterbirds in Pobitora Wildlife Sanctuary
What are migratory birds?
The migration process of bird is a natural phenomenon. Although all birds are not migratory, in India every year we receive a large number of birds especially as our winter guest from different parts of the world. According to various studies, the migration patterns of different species of birds are different. The majority of birds start their journey from northern summer areas to southern wintering ground. On the other hand, factors like altitude , in moving to high altitude in summer and residing in low lands during winter, also plays significant role in determining the migration pattern of the birds. Moreover, the perfect morphology and physiology enable those birds to fly so high and long distances. During their long journey, migratory birds lose body weight considerably. Therefore they prefer to take frequent rest along their journey and feed to make themselves fit to reach the next destination.
Bar-headed Geese, one of the highest flying migratory birds in the world, can be seen in large numbers in Pobitora every winter.
Importance of migration
Birds migrate from areas of low or decreasing resources to areas of high or increasing resources mainly. Those resources include primarily food and nesting colonies. In several parts of the world where migratory birds travel through and reside, they play significant role in maintaining the ecological balance of those areas through different ways. Sometimes they act as pest control agent by feeding insects and other organisms that harm agriculture crops. The seeds and fish eggs dispersal are two well known roles play by migratory birds and that directly helps in maintaining the ecological balance of different areas. The widespread presences of migratory birds in an area also indicate the good ecological condition of that area and it helps in analyses the state of environment of it.
Painted Stocks, a rare winter migrant to Pobitora forging in the wetland along with Black-headed Ibis.
Pobitora- the heaven of winter migrants
Every year, the winter migratory birds make their way to India through the central Asian flyway, covering a large area of Europe-Asia between the Arctic and Indian Oceans. During this season, Pobitora Wildlife Sanctuary witness large number of winter migratory birds and therefore it is known as the heaven for winter migratory bird. The wildlife sanctuary is situated on the southern bank of river Brahmaputra, at Morigaon district of Assam covering 38.85 km sq. It is also the dwelling place of the Greater Indian One-Horned Rhinoceroses which harbors the highest density in the world. As it is only 45 km away from Guwahati, the capital city of Assam, with good connectivity, people prefer to visit Pobitora even if they have limited time in their hand.
A scene from Timuliduba wetlands of Pobitora during winters
The birds normally start coming from October and they stay there till the month of March. Pobitora due to its mesmerizing scenario with thousands of migratory bird attracts many tourists every year. There are several beels or wetlands such as Tamulidoba, Pagladuba, Haisora, Lambaduba, Noltoli and Jogdol which attract thousands of water birds to the wildlife sanctuary every year.
Aaranyak, a scientific research organization working for biodiversity conservation in Northeast India in collaboration with the Pobitora forest department and other local NGO’s has been conducting “Annual Water Bird Census ” for past 2 years in the sanctuary. The census has recorded a good number of individuals of several bird species, e.g more than 15 thousand in 2020 and more than 24 thousand in 2021, which also include few rare ones. Birds like Lesser Whistling Teal, Eurasian Teal, Pintail Duck, Northern Shoveller, Mallard, Eurasian Wigeon, Ferruginous Pochard, Grey-headed Lapwing, Black-headed Ibis, Grey-lag Goose, Bar-headed Goose, Eurasian Coot, Common Pochard, Ruddy Shelduck etc. are few of the most common and abundant winter migrants of Pobitora. On the other hand, species such as Greater White-fronted Goose, Gadwall, Painted Stork, Baikal Teal etc. are seen in smaller numbers and can be considered as rare in the area.
Birdwatchers participating in Annual Waterbird Census in Pobitora
The main objective of this census exercise initiated in 2020 is to monitor variations in bird species and their numbers every year and to keep long term data generation for scientific understanding and conservation of birds.
A flock of Lesser Whistling Teal, a resident species and an Eurasian Coot, migratory to Assam are common waterbirds seen in Pobitora in large numbers.
The roadside area of Pobitora wildlife sanctuary is a convenient spot for common visitors who almost every alternate day go there to enjoy the beauty. Tamuliduba beel, one of the several wetlands of Pobitora, situated alongside the connecting road to Morigaon, is a favourite place for photographers and bird lovers during winters as it becomes the hub of migratory birds during that time. It is also seen that people who are newly developing their skills in those fields, also prefer to visit this site frequently during winter as it gives easy access to such birds. People spending time while crossing road to the villages, is also a common scenario of that area.
There are as many as 1,275 species of birds has been recorded in India as of 2020 (Birds of India checklist with classification), of which 78 are endemic to the country and 212 species are globally threatened. As per a recent report with assessment of 865 species from India based on 10 million observations by birdwatchers, 52% of the species shows decline over the past decades while 101 species classified as High Conservation Concern requiring immediate attention.
There are different factors which impact the migration pattern and population size of those birds. Even though most of them are manmade causes, in the meantime the natural causes also can’t be ignored. The loss of habitats due to encroachment for settlement, agriculture, deforestation activities for economic benefits, high-voltage power lines, wind turbines etc. are some of the human induce causes. Poaching is another prevalent factor that we can witness in northeastern region. Among natural causes, the role of climate change plays significant role in determining the migration pattern of birds.
Greater White-fronted Goose, a rare winter visitor to Pobitora
It is possible to change human induce factors with our own initiatives, for example - Amur falcon hunting practices in Nagaland earlier was very common. But as a result of awareness drives taken by NGO’s and other government organizations, the hunting practices have successfully been controlled in the state. So it is necessary for us to come forward to understand and minimize those factors and welcome migratory birds from different parts of world to our land. Apparently, flying over long distances means inclusion of different international bodies and political areas with their own environmental politics, conservation measures etc. Therefore, transboundary cooperation between governments, NGO’s and other stakeholders is required to ensure the safe pass of migratory birds to reach their destination.
About the Author:
Munmita Boruah is the Executive Editor of ecoNE and a participant of Annual Waterbird Census in Pobitora Wildlife Sanctuary.
You can reach her at firstname.lastname@example.org