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Whale strandings due to 'seismic activity'

The Irish Times

The Irish Times - 6th May 2000

A marine biologist has warned that the increased incidence of strandings of a rare whale species may be due to underwater noise pollution caused by exploration companies.

Dr Simon Berrow, chairman of the Irish Whale and Dolphin Group, said increased seismic activity of exploration companies off the west coast could have contributed to the deaths of four Cuviers beaked whales over the past two months.

The species, one of 79 whale species, can grow to about 20 feet, but the most recently discovered one, found last weekend near Ballyferriter, Co Kerry, is little over half that length. They are "a deepwater, offshore mammal", Dr Berrow said. But little is known about the beaked-whale family, of which are there are 15 recognised species.

Over nine days in March, two were washed up in Co Clare, at Doonbeg and Doolin, and a third was found at Rosses Point, Co Sligo.

Between 1901 and 1995, just 21 strandings were recorded, a rate of one every four years, said Dr Berrow, and although it was hard to prove that acoustic activity was disorienting the whales "there is enough evidence to show these acoustic surveys and especially the low frequency active sonar is affecting these beaked whales".

He cited two recent cases where acoustic activity affected Cuviers beaked whales. In May, 1996, there was a mass stranding along the Greenland coast, linked to acoustic tests being carried out by a NATO vessel doing submarine-detection research. Last March, another mass stranding of beaked whales occurred in the Bahamas, during US Navy sea tests involving mid-frequency active sonar for underwater detection.

"Whales and dolphins do not live in our world. They live in an acoustic world where sight is not a useful sense. They are amazingly well adapted to living underwater. "Probably the most growing concern for whale conservationists around the world is the noise pollution in the seas."

Dr Berrow is also project manager of the Shannon Dolphin and Wildlife Foundation, which is seeking to develop the Shannon Estuary as a tourist attraction for dolphin watching in a sustainable manner.

He added that the "huge seismic survey effort" which included the surveying of 46,000 square kilometres of sea since 1997 going on off the west coast of Ireland involved no environmental impact assessment, even though Irish waters were declared a whale sanctuary in 1991.

About 70 per cent of the State's mammalian fauna lived in the sea yet conservation efforts were largely confined to land animals. "We are still facing the challenge that nobody takes into account the cetaceans off the Irish coast," he said.

Seismic exploration uses a high intensity, low frequency spectrum, sending out a "bang" every 10 seconds, which dolphins avoid. "For beaked whales that inhabit deep underwater canyons, the effect may be much greater," he said.

Enterprise Oil, which is carrying out an EIA for development of the Corrib gasfield, off the Mayo coast, does not have to include the potential effects of seismic activity on marine life because the Department of the Marine or Dúchas have not insisted on it.uchas could insist on it as part of the licensing requirements," he said.

Companies such as Enterprise Oil, Marathon and Statoil had to fulfil their legal and moral obligations, he added, by funding the appropriate research to mitigate against the effect of their activities. He said the forthcoming seven-year seabed survey, recently announced by the Minister for the Marine, Mr Fahey, should include surveys on the whale and dolphin populations and their habitat and ecological requirements.

"We do not know the habitat requirements, we do not know the distribution, we do not know their seasonal abundance, we do not know their feeding requirements," he said.

The cost of a cetacean survey would be "a couple of hundred thousand pounds" compared to the £21 million cost of the seabed survey.

While the exploration of marine resources was to be welcomed, he said it would have the biggest effect yet on the Irish marine environment.

The State was also obliged to minimise the effect of this development on marine species. There were 23 cetacean species, including whales, dolphins and porpoises in Irish waters.

"It is about time the whales and dolphins in Ireland were given a bit more thought and credence. There are hundreds of thousands of dolphins in Irish waters. Yet everyone goes mad for Fungi and ignores all the others."

Gray whales with Winston
Save the Whales

Posted Date: 
6 May 2000 (All day)