Dead whales that washed up on Irish beaches 'may have been killed by military sonar'

‘Catastrophic event’ likely to be behind ‘highly unusual’ multiple strandings, says marine conservation group

Up to eight Cuvier's beaked whales have been found dead on Ireland's west coast within a week (Gareth and Amanda Doherty)

British military sonar may have caused the deaths of eight whales which washed up on Ireland’s west coast, scientists have said.

The bodies of five Cuvier’s beaked whales have been found hundreds of miles apart in the past week, along with another three believed to be of the same species.

The Irish Whale and Dolphin Group (IWDG) said it was “highly unusual” for multiple deaths to occur within a short period.

Simon Berrow, the marine conservation charity’s chief scientist, said between one and three Cuvier’s whales were typically found stranded on Ireland’s shoreline each year.

“To have quite a few whales all dying at the same time, it has to be a catastrophic event,” he told The Independent.

Two of the whales were found on 4 August on the coast of County Donegal and the carcass of another was discovered in County Mayo the same day.

Another washed ashore in County Galway on 3 August and a fifth was discovered at a beach in County Sligo on Tuesday.

Two further bodies, believed to be Cuvier’s whales, were found on the shores of Donegal and Galway this week, while an eighth is thought to have been spotted floating near to Inishbofin island by scientists onboard an Irish research vessel.

The IWDG said all the whales were in a “poor but similar condition”, suggesting they had died around the same time.

Cuvier’s beaked whales are a deep-diving species “particularly vulnerable to low-frequency active sonar, which are used to try and detect submarines”, according to Dr Berrow.

He said: “In an event like this, you obviously try to explain the potential cause of it so naval exercises would be an obvious first thing to consider.”

The whales were unlikely to have died of starvation or disease because they were “chronic conditions that would manifest over a longer period”, he added.

The Irish Navy is not thought to have sonar capabilities but Britain’s Royal Navy regularly carries out training operations using the technology.

A Royal Navy spokesman said: “There is no evidence that the deaths of these marine mammals have been attributed to any Royal Navy Sonar operations, trials or exercises.

“We take our environmental responsibilities very seriously and continue to work with the relevant UK authorities to reduce any environmental risk.”

Between December 2014 and April 2015, 11 Cuvier’s beaked whales were found stranded on Ireland’s coast, around the same time a similar number were recorded in western Scotland.

The IWDG said the strandings coincided with naval manoeuvres following the reported sighting of a foreign submarine in British waters. No connection between the whales’ deaths and the naval manoeuvres was established.