Recovery of a colour flagged curlew sandpiper at Point Calimere near here by the ornithologists of the Bombay Natural History Society’s Bird Migration Study Centre (BMSC) has indicated a possible shift in migratory trend of the avians that traverse up to 11,000 km from their breeding grounds in the Arctic region to Point Calimere and the adjoining the Great Vedaranyam Swamp.
The bird that was caught here a couple of days back was colour flagged in Chilika in Odisha and marked there on January 16 by some bird migration study experts. When the curlew sandpiper was recovered here by the BMSC experts, their joy knew no bounds as it was at once interesting and revealing.
“Though we can’t conclude immediately whether the bird went to its regular breeding spot in the Arctic and returned or had simply flown east heading straight to Point Calimere, our surmise from the findings is that it has returned from an unsuccessful breeding sojourn,” says Deputy Director of the BNHS and in-charge of the BMSC S. Balachandran. However, from its feather pattern it seems that the bird has travelled a great distance, he adds.
Dr. Balachandran observes that the episode might also reveal a shift in the migratory pattern of the birds. “Migratory birds such as the curlew sandpiper, weighing just 70 gm and flying over 7,000 km in just about a week, arrive here only by late August. But its early arrival necessitates a study on whether there might be a shift in their migratory pattern due to any adverse influence on mud flats en route and other habitat spots,” he says.
Most of the birds that fly into Point Calimere travel from their breeding grounds in Central to North East Russia while some come from their China, Mongolia, West Asia or Eastern European homes. In the case of the Arctic birds, they leave their breeding grounds in the icy tundra during the northern winter and fly more than 8,000 km to reach Point Calimere and the shallow slat marsh lands in the Great Vedaranyam Swamp. Flamingoes, ducks, gulls, terns and shore birds or waders come in large numbers from late August and leave by February end.
During that season BMSC scientists undertake bird ringing depending on the catch, despite the funds crunch that has hit their conservation efforts badly. “Migration study and recording, through ringing and colour flagging, reveal stop over sites, patterns, the bird's health and physical parameters. That immensely helps in the conservation of endangered species especially,” says research ornithologist Tuhina Katti from Pune, pursuing the birds at the BMSC.