Time: 2:30 at night
Place: Any road on a metro
Scene: The road is desolate with an occasional passing vehicle. A flock of crows are searching for food. While one is busy investigating a food packet with its beak, another scavenges an open garbage dump.
Behavioural patterns of animals and birds are changing in Indian metros due to pressure of urbanisation.
Scientists explain behavioral patterns, including biological clock, of animals are changing in big cities like Delhi, Mumbai and Kolkata.
“Some animals, living in the city, are behaving abnormally. This is mainly due to urbanisation that has encroached upon their habitats. Sound and light pollution round the clock are also putting them under stress,” said Lalita Vijayan, head of the ornithology department at the Salim Ali Centre for Orinithology and Natural History, Coimbatore.
Though they haven’t undertaken any specific studies, Vijayan admitted scientists have reported some peculiar behaviors of some species of birds.
“Scientists in Pune have spotted crows behaving like kingfishers and kites. As the city became cleaner their food became scarce. Crows began swooping down into tanks from branches above to catch fish,” she added.
“The biological clock of certain animals is changing due to urbanisation,” remarked Gopinath Maheswaran. He is a scientist with the Zoological Suervey of India, based in Arunachal Pradesh and has been studying animal behavior for several years.
Birds like crows and drongo are active during the day. But the forces of city life are bringing them out during night.
While bright city lights steal their nights, some hotels dump their leftovers at the dead of night. The birds feed on these.
“The sodium vapour lamps attract a lot of insects, compelling the drongos to feed on them at an hour when they normally rest,” said Maheswaran.
Such reports have poured in from from smaller towns too.
According to S Ghosh, veterinary surgeon with Kolkata’s Alipore Zoo, the effect of urbanisation is clear in the zoo itself.
“There are quite a few eateries outside the zoo boundary wall. They are open till late in the night. The crows and shalik that live in the trees near the wall are awake till late in the night due to the sound and availability of food,” he said.
“But the ones deep inside the zoo behave normally and are never found awake after sunset”.
Even dogs are changing their habits.
KK Basu Roy, a Kolkata-based dog expert, said earlier the street dogs used to mate in the month of August and September. But now, they mate round the year. He further said adding this was yet another effect of urbanisation.