Ships threaten whales along Kerala coast

Thiruvananthapuram: Increasing number of deaths of marine mammals and stranding of endangered whale species along the Kerala coast in recent months, apparently due to collision with ships, has highlighted the need to develop appropriate mitigation measures, a study has said.

In the past few months there have been reports of at least a dozen deaths of marine mammals along the coast. In addition to that, four whales stranded in 2010 and this year were identified as Bryde`s whale, an endangered marine species, A Biju Kumar, Head of the Department of Aquatic Biology and Fisheries, Kerala University, said.

Marine mammal mortality due to fishing operations was identified as a major threat to their population and this was true with regard to death of dolphins and porpoises in Kerala coast, Kumar, who conducted a study on the issue, said.

However, he said many of the deaths and ship strikes on mammals were not properly documented and identified. The high number of reported whale strandings in the past few years seems to indicate that the frequency of these events have increased, he said.

While globally anthropogenic encroachments such as contaminants and intensive sound disturbances, which derange the natural behaviour of the whales, have been considered to be a cause, along the Indian coast the primary reason for the killings could be collision with ships, he said.

Several whales stranded were found with serious injuries, probably due to collision with propellers, he said. "Ship strikes can significantly affect small populations of whales, and in areas where special caution is needed to avoid such events, measures to reduce the vessel speed may be beneficial," he said.