(Pictures courtesy: K Antony Xavier)

A Possible Reason

TUTICORIN/CHENNAI: At least 45 small whales (short-finned pilot whales), part of the lot which washed ashore in Tiruchendur in Tamil Nadu on Monday evening, have died. More than 100 whales were found on the 16km stretch from Alanthalai to Kallamozhi coastal hamlets on Tuesday morning. Thirty six of them have been rescued by fishermen."The whales started reaching the shore in groups around 5pm. It is very strange. In 1973 when we were boys, we witnessed same phenomenon. However, not these many washed ashore then," said Rajan, a fishermen in Manapad.Ditto Mascarenhas of Kulasekarapattinam said if local fishermen had not kept a vigil, many more whales would have died. The fishermen remained awake the whole night to keep the whales in water by pulling them back to the sea.Tuticorin district collector M Ravikumar inspected the coast. He said officials were investigating the reason for such a huge number of whales reaching the shore.A team from the Gulf of Mannar Marine National Park in Ramanathapuram has rushed to the spot.Former director of Zoological Survey of India K Venkataraman said cetaceans (whales, dolphins and porpoises) are social marine mammals. They live in groups and if the leader of the group is disturbed due to changes in underwater, they get disoriented immediately. They start drifting from their normal path and head towards the shoreline, leading to their deaths.Moderate earthquakes, geo-magnetic deviations, sonic waves and tidal currents could disorient cetaceans.On Monday, an earthquake with a magnitude of 6.5 on the Richter scale and another one measuring 6.9 on the Richter scale were in the Philippines and Indonesia, respectively. These could have disoriented the whales.In India, the first ever report of mass stranding of this whale species was reported in Salt Lake in Kolkata in 1852. The maximum number of whale stranding on Indian coastline happened in 1973 during which time 147 whales got stranded, Venkataraman said.Annually world over 2,000 whales get stranded. More than 1,500 whales have been stranded along the Indian coastline since 1800 till 2015.So far no study on this issue has been taken up in the country, lament researchers. One of the reasons is that not many funding agencies are ready to finance the study.Study on population dynamics of cetaceans, their breeding ecology, habitat degradation and other related issues needed to be taken up by the government. Only such an effort would help in protecting these endangered marine mammals.