- Chinmay Nath, Minerva Academy, Mayong
With the onset of winter, one day I visited the Pobitora Wildlife Sanctuary. I saw many birds there, like Pond Heron, Egrets, Lesser Adjutant Stork, Greater Adjutant Stork, and many ducks including many migratory birds which I could not identify. A question came to my mind about these migratory birds, how do the birds find their way to Pobitora while migrating.
Migratory birds are those birds which leave their place of nesting when the climatic conditions become adverse for their survival. Sometimes they migrate to another continent. Some birds leave their abodes in winter and go to another place where the weather is warmer. They do so because it is difficult for them to survive on colder regions.
The birds generally eat insects and worms, and during the winter their food becomes scarce. Hence, they migrate to warmer places. Studies suggest that birds orient themselves to the compass points using the position of the Sun during the day and with the help of stars at night. They can also sense the magnetic North. In addition, they also use other clues like visual layout of land, smell (of sea), sound (of waves on shores, wind through mountain passes), etc.
The most amazing aspect of Birds migration is that though birds abandon their young ones as soon as they fledge, and a short time later, the young ones grow up to take the same migration routes on their own year after year.
From the Natural history desk of ‘The Seed’:
Chinmay Nath points out to the most intriguing natural phenomenon witnessed for ages by generations of human beings in different parts of this planet. In India, especially in Assam we are accustomed to the incoming of thousands of winter feathered visitors from different parts of the colder Northern hemisphere. These bird species that arrive in a fixed timeline during the winter months of December to January come here to adorn our forests, lakes, wetlands, water tanks, and even cultivable lands for a stipulated period of time. They usually set out to their summer abodes after the month of February – March every year. Though we commonly consider avian migration as a winter phenomenon, there are many species of birds like Cuckoos, which are summer visitors in India.
The migration of birds remains a mystery to human beings till date, despite continuous research and many hypothesis been postulated to explain this annual avian migrations on earth, the scientists are yet to provide concrete evidence and theories to explain the unbelievably well-timed, and meticulously maneuvered yearly migration of birds from one part of the world to another across continents, usually it is from the colder Northern parts of Earth to the warmer southern parts where food remains available throughout the year, even during the winters due to various physical, climatic, and ecological factors. This intriguing natural phenomenon calls for in-depth understanding of Nature, the seemingly unintelligent and non-thinking birds have outwitted the technology laden human scientific acumen for all these years; the secret behind the perfectly executed avian migrations that predates the advent of human beings on this planet tempts the naturalist hidden in each of us to delve deeper, observe, and analyze the natural world more closely, at times more intently to grasp the missing link which disabled us for ages to understand this phenomena with firm findings.
Chinmay Nath resides very close to Pobitara Wildlife Sanctuary in the Morigaon district of Assam. Pobitara Wildlife Sanctuary attracts bird lovers, wildlife lovers, and bird watchers from different parts of India during the winter months because of the seasonal boom in the avian population of the area due to arrival of large numbers of migratory avifauna. The Pobitara wildlife sanctuary is known as a rich wild birds’ habitat in Assam, it is home to more than 200 species of birds. It provides wintering ground for nearly 70 species of migratory birds every year, a large section of this are water fowl species which throng the numerous wetlands of Pobitara and the nearby areas. The 38.85sqkm area of the Pobitara Wildlife Sanctuary harbors this immensity of life forms because this is supported by the ecology of the greater Pobitara region which consists of a network of wetlands, widespread grasslands, and small area of woodlands along with few hills situated in the floodplains of the Brahmaputra River systems within the geographic area of the historic Mayong region of Assam. The Pobitara Wildlife Sanctuary, internationally acclaimed as the area with the highest population density of One Horned Rhinoceros comprises a part of the Mayong region of Morigaon district in Assam. Most of the migratory species visiting the Pobitara Wildlife Sanctuary are water birds, and ducks. While we remain mesmerized with the incoming of large folks of these winter visitors every year, we ought to learn about their needs, and the threats faced by these species due to the changing ecology of Pobitara Wildlife Sanctuary, this will contribute in adopting correct conservation measures for their protection. For this we must know about the structure and composition of the Pobitara Wildlife Sanctuary because the future of wild birds in this wildlife sanctuary are facing a diverse range of threats apart from poaching and illegal killing by miscreants.
The gravest threats are from habitat destruction and habitat change. The landscape and vegetation of the Pobitara Wildlife Sanctuary presents a beautiful example of ecological succession as seen in the gradually merging landscape of river, wetlands, submerged lands, to grasslands, and flood tolerant sparse woodlands which are dominated by trees of medium height inside the wildlife sanctuary. The percentage of woodland is negligible compared to land covered by wetlands and grasslands. This represents a forest which is still evolving, a forest which is yet to achieve its ecological climax. The natural ecological succession drives the gradual transformation of this floodplain’s ecosystem from wetlands and grasslands to that of full-grown woodland forests. This natural flow of evolution in Pobitara Wildlife Sanctuary is been hindered by human interference with timely burning of the grasslands, cleaning and dredging of the wetlands to remove invasive and aggressive species to maintain the ecosystem of the Pobitara Wildlife Sanctuary in the present state to sustain the life supporting system of this ecosystem. Most of the water fowl depend on the grasslands and wetlands for food, hence preservation of the wetlands is very important for these migratory species. Wetlands are threatened by both natural and man-made causes, the wetlands inside the wildlife sanctuary are protected under the Wildlife Protection Act of India 1972, but the wetlands outside the wildlife sanctuary remain threatened mainly due to change of land use pattern.
With expanding urbanization and population growth, the wetlands are often converted to agricultural lands or for other purposes. Moreover, there are no legal provisions to protect the wetlands from such exploitation and destruction in India because wetlands are not yet categorized as forest areas. Along with the wetlands the natural grasslands are also important source of food and nutrients, an integral part of the wetland ecosystem. Hence, protection of the grasslands is also crucial though it is very difficult to find natural grasslands outside the wildlife sanctuary because rest of it is already been converted to paddy fields and cultivable lands. But the worst situation will be losing these open cultivable lands to industrialization and urbanization. The Pobitara Wildlife Sanctuary and the nearby areas are adorned with many wetlands like Haduk Beel, Tamuliduba beel, Hahsora beel, Pagladuba beel, Lambaduba beel, Naltoli beel, Jogdol beel. It must be remembered that best conservation plan for Pobitara Wildlife Sanctuary must focus on preserving the natural wetlands of this area. The wetlands outside the area of the wildlife sanctuary are equally important for the sustenance of the avian diversity in the Pobitara wildlife sanctuary, hence a holistic community-based approach for preservation of the wetlands in and around the Pobitara Wildlife Sanctuary will play a significant role in the future course of wild birds’ conservation in Pobitara. The local community must come forward to compassionately share the wetland resources with the wild birds and other wildlife of the area. In this regard, the young generations of Mayong region have a vital role to play as they will be the future decision makers of these natural resources. It is very important for the young students to learn well about the biodiversity and ecological aspects of Pobitara Wildlife Sanctuary and the entire Mayong region to lead a future of progress through judicious choices based on prioritizing biodiversity conservation and social responsibility towards the preservation of the natural wildlife habitats in the surroundings of the wildlife sanctuary.
The many questions raised by Chinmay Nath in his write up regarding the mystery of avian migration can be studied at Pobitara Wildlife Sanctuary and the nearby areas by the young students from Mayong, through their active interaction with Nature and keen observation of their natural surroundings, of the forests, wetlands, hills, and the wild birds, other wildlife in their environment. They must enrich these observations with in-depth studies through reading relevant books and continuing their quests by nurturing their curiosity to solve the numerous mysteries of the natural world like ‘migration of wild birds’ across the globe. The students who are interested in these studies can further strengthen their knowledge by participating in trainings and nature-camps organized by Nature’s Beckon. The children and young students of Mayong are blessed with the possibility of discovering many new aspects of Nature, if only they can realize their privileges in this regard.
(Gratitude to
Sri. Debajit Nath, for supporting this write up with your photography.)