BANGALORE: Winged guests, who make Bangalore their home every winter and stay on till the second week of May, have left the city early this year. Experts blame it primarily on habitat degradation, with most lakes in the city fast turning into sewage hubs. On Unesco-declared World Migratory Bird Day on Saturday , it's perhaps timely to look at the pattern of birds moving out of the city early.
"The current practice of lake development is not biodiversity-friendly. The once-seasonal lakes are now perennial. These water bodies have undergone a huge change in structure and ecology," said S Subramanya, a bird expert in Bangalore.
The city's lakes, which were once filled with clear water, are now full of sewage, thereby affecting adversely the number of migratory water birds. "The decline in bird count has been considerable and a few species have stopped coming altogether to Bangalore," said Subramanya.
The habitat modification, namely the change in structure of lakes, is affecting the migratory bird count, experts agree. "The fishbowl type of lake management (lake deepening) deprives shore birds of their habitat. So the waders which used to come to the city in search of shallow water started giving Bangalore a miss," said Seshadri KS, a bird-watcher. Take Hebbal lake for instance which had over 2,000 Northern Shovellers and Eurasian Garganeys earlier. This year there were none. "Also, most homes in the city today are devoid of shrubbery and that does not allow birds to settle down either," said ornithologist MB Krishna.
Climate change
Is climate change the other big reason? There's speculation that with global warming, the northern latitudes are getting warmer. Those being the breeding ground of such migratory birds, they are eager to get back there. "It is an attempt perhaps to escape inclement weather," said Subramanya. It's believed that one-sixth of the total bird species in Bangalore are migratory birds.
The usual season of migratory birds in Bangalore is between October (sometimes last week of September) and April-May. "The pressure along the migratory birds' way may be equally responsible for the fastdeclining count," said Ullas PA, a bird-watcher in Bangalore.
Migratory birds on the decline
Western Marsh Harrier
Greater Spotted Eagle
Common Kestrel
Northern Pin Tail Duck
Northern Shoveller Duck
Garganey Duck
Common teal
Waders Godwits
Sand Plover
Little Stint
Temmink's Stint
Times View
Migratory birds are a birdwatcher's delight and as it happens very good indicators of the quality of a city's water bodies. Not so long ago, Bangalore's many clean lakes were welcoming centres for a host of migratory birds fleeing the colder areas in northern latitudes. Over time, these lakes have fallen victim to encroachment, neglect and disuse and this is being reflected in either migratory birds not coming anymore or leaving early. It's time to revive lakes and ensure they're restored to their original glory.
