Ornithologists, more commonly known as bird-specialists, state that the migratory pattern of the winged species may show marked variations as they tend to gravitate towards areas that presently offer them desirable food and better habitats
A drastic decline in the arrival of winter migrants including the Bar-Headed Geese and Demoiselle Cranes in the state is “not alarming” as the birds are heading down South for better habitats, say environmentalists.
With winter on the threshold, migratory birds from Central Asia, Siberia, Gulf and Europe have started visiting the state in large numbers in search of food and to set up their temporary habitats. Even though the arrival of the winged beauties has been vaguely delayed this year mainly due to the slight change in the climatic conditions, birds like rosy busters, sparrow hawks, blue-throated warblers, goshawk, peregrine falcon, greylag goose, northern pintail, green-winged teal, gadwall, mallard, pied and yellow wagtails, lesser sand plover, Northern pintail, Common teal, verditer fly catchers, red breasted canaries, common pochard, flamingos, painted stork, and white gloss ibis among others, have started flocking the Western Ghats and Deccan Plateau.
However, there has been a drop in number of wader birds including the Bar-Headed Geese, Demoiselle Cranes and Pintail Ducks in Maharashtra since past five years due to the change in the climatic conditions and also unavailability of food. The findings by ornithologists have set the alarm bells ringing, as there has been almost 80 percent reduction in the numbers of these birds arriving in the state. The decrease in population is being mainly attributed to weather conditions and changed plantation of crops. According to them, since lentils are being replaced with sugarcane plantations in most parts of the agricultural fields in the plateau, the birds are changing their direction and flying Southward.
As the winter season is harsh in the northern region and its gets difficult to find food, these migratory birds visit India in November and stay till March-April before flying back. But their duration of stay can also vary depending on the weather condition.
According to Dr Asad Rahmani, a bird expert, the waders, which supposedly have been eluding the Western Ghats, sometimes fly back in what is called ‘return migration’ in large numbers. “During migration period some birds congregate in small numbers and then fly further down South after which a new lot arrives. The gathering of the geese and the cranes is better in North and South India where they find a suitable habitat compared to Maharashtra, where cropping patterns are altered. These waders do not feed in wetlands but on cropland where the soil is good.”
Accordingly, in the Census conducted by the Bombay Natural History Society (BNHS) last year, an estimated population of about 71,000 bar-headed geese was recorded in the Pong Dam wetland in Himachal Pradesh after which data on its population in the wild was revised by International Union for Conservation of Nature (IUCN), which listed the birds in the category of endangered species.
However, the number of Bar-Headed Geese spotted in the Western Ghats has dropped to about 100 from an estimated 4,000 since the past five years.
Similarly, the wader birds- Demoiselle Cranes too have been eluding Maharashtra due to unavailability of food, experts claim. These cranes breed in Central Asia, migrate to South Asia and are seen in Northern India and in some parts of Gujarat during winter.
“Along with the bar-headed geese, the habitats of several other species, including the dam demoiselle cranes, Pintail Ducks and Ruddy Shelducks are also threatened. Due to climate change, these migratory birds miss out on vital food as it does not match the fruit-bearing season. Unavailability of food can affect their reproductive ability and that can have an impact on their population,” said a Pune-based ornithologist.
“The Demoiselle Cranes which are mainly found in Rajasthan and Gujarat during their migration period mostly visit dams in Maharashtra in search of food. But there has been no concrete evidence to show that their habitat is being destroyed. For e.g. a drought in the year 1987 left all dams in Maharashtra without water and due which the cranes changed their route and went to Goa. That shows that the birds fly to places where conditions are favourable to them,” said Rahmani.