Migratory birds bid adieu to city’s green zones, start north-bound journey

THANE: The winter migratory birds have started flying back home after seeking refuge in the green zones and shorelines of the city and its neighbouring areas for close to three months.
From the himalayan verditer flycatchers that stayed in the Yeoor region and green pockets of the city to the himalayan stints and the Russia and China-based godwits that fed on crustaceans, molluscs and invertebrates in the wetlands along the coastlines, many of these species have already kickstarted their journey towards the north.

“During winter, the northern regions, which usually house these birds undergo extremely cold climatic conditions, including frozen lakes, snow covered lands and so on. As they can’t find food due to such climatic conditions, they fly down to Mumbai or Thane where the temperature is bearable,” said Sandeep Jagtap, city-based bird watcher. While the birds spent their first two months touring different forest areas and wetlands and feeding on the available food and basic recourses, environmentalists and avifauna experts said the birds spend around 15 to 20 days in feeding and fattening themselves to prepare for their homeward journey.

“It takes these birds a lot of energy to fly at high altitudes and speeds for 10 to 15 days that it takes them to get home. To prepare their bodies for this journey and unavailability of proper food on the way home, they keep eating and fattening themselves for a continuous plan of two to three weeks before leaving,” said Avinash Bhagat, avifauna expert and member of city-based environmental NGO Paryavaran Dakshata Manch.

“Birds fly at different speeds depending on the wind directions, air pressure, thermal air, threat of predators, height of their flight and number of rest stops they have, all of which are never fixed. When weather conditions are favourable, they do not even need to flap their wings, and can just glide at 50 to 60km per hour. Some birds can fly for days at a stretch,” said a member of the Bombay Natural History Society.

While many of these birds have started travelling north, experts said that bird enthusiasts still have a couple of weeks to spot some of the winter migratory birds thanks to the delay in their migratory patterns.