Whales: India
This is a collection of articles archived for the excellence of their content. |
Songs
2021: recorded in Lakshadweep’s waters
lakshadweep/articleshow/84060442.cms Ruchika Uniyal, July 4, 2021: The Times of India
From: lakshadweep/articleshow/84060442.cms Ruchika Uniyal, July 4, 2021: The Times of India
When Divya Panicker landed in Lakshadweep in 2015, more than one fisherman she met claimed to have spotted large whales in the archipelago. But beyond these anecdotal sightings, the scientific community had little documented evidence of the presence of the endangered species in these waters. And if the marine mammals were indeed present in these parts, were they permanent residents or merely passing by?
Six years later, Panicker has some answers. “For the first time, we have recorded pygmy blue whale songs in these waters. This is conclusive evidence of their persistent presence in Lakshadweep,” said Panicker, who is pursuing a PhD in Oceanography at the University of Washington.
Whales are difficult to study – they travel large distances and stay underwater for several minutes. It is easy to miss them during visual surveys, especially if the weather is rough. “There were some strandings (when marine mammals come ashore) that were talked about by locals or sightings by fishermen,” said Panicker, who grew up in Kerala and first visited Lakshadweep to study the marine mammals as a researcher at the National Centre for Biological Sciences, Bengaluru.
Some records dating back to 1960s and 1970s from illegal Soviet whaling also mentioned blue whale catches near Lakshadweep. “Thanks to technological advances in the last few years, acoustic detection is now widely used to study whales and other vocal marine mammals. At the University of Washington, I learned how sound can be a very effective tool in studying marine mammal distributions and populations. Listening to whales sing is fascinating and I immediately got hooked on to this track of investigation,” Panicker told TOI.
So in December 2018, she went underwater to set up a microphone to record whale calls at Kavaratti island. Another recorder was put on the other end of the island. Analysis of recordings showed whales with a peak activity in April and May.
“Pygmy blue whale songs peaked just before the southwest monsoon season in the months of April and May indicating blue whales use the Lakshadweep atolls seasonally. This raises questions on what the whales were using the area for during this season? Perhaps, the whales are travelling through this area but not remaining there. Or this area may provide feeding opportunities during these months,” she said.
Panicker, who published her findings in the journal Marine Mammal Science, said “an incredible amount” of blue whale acoustic diversity occurs in the ocean basin. “Although pygmy blue whale populations don't look very different at sea, their songs allow us to identify different populations. Prior studies — mostly conducted in the southern hemisphere — show at least four different blue whale songs occur in the Indian Ocean. Just over the last year, two more songs from the northern and central Indian Ocean have been attributed to pygmy blue whales — the Oman and Chagos song respectively,” she said.
Panicker added that the song type that she recorded in her study was the same as the one recorded in the 1980s off the Sri Lankan coast. She added that any development plan in Lakshadweep should “take into careful consideration its unique ecology, geography and culture and the realities of a changing climate”.
Notably, the Indian government has plans to develop Lakshadweep for tourism, a move that has invited criticism from several quarters.
