Naval sonar threatens whales says UN report

High intensity naval sonar poses a serious threat to whales, dolphins and porpoises that depend on sound to survive, according to a new report by the United Nations Environment Programme.

The study lends the first official support to allegations by environmental groups that military manoeuvres are responsible for the increasing incidence of mass whale beachings.

"While we know about other threats such as over-fishing, hunting and pollution, a new and emerging threat to cetaceans is that of increased underwater sonars," said Mark Simmonds of the Whale and Dolphin Society.

"These low frequency sounds travel vast distances, hundreds if not thousands of kilometres from the source."A coalition of environmental groups launched by, among others, Jean-Michel Cousteau, son of the ocean explorer Jacques Cousteau, sued the US Navy in October over its use of sonar, saying the ear-splitting sounds violated environmental protection laws.

The lawsuit, which is ongoing, is aimed at vessels that use mid-frequency sonar to locate submarines and underwater objects.

The navy has 60 days to respond to the action.

Tests on the bodies of seven whales that died near Gran Canaria in 2002 found haemorrhages and inner ear damage, which experts said was caused by high-intensity, low-frequency sonar used in the area, it added.

There are no laws governing noise pollution in the world's oceans, but western governments, considered largely responsible with their increased military presence in the seas, say they need more research before taking action.

The Australian Department of Defence has admitted that two of its minesweepers used short-range, high-frequency sonar to search for a shipwreck off Marion Bay, where 110 pilot whales died in two incidents on last month.

The ships were looking for a 360-year old Dutch shipwreck.

But the defence officials denied any responsibility for the strandings, saying the first one took place while the ships were still anchored off the Tasmanian capital, Hobart, a significant distance to the west.

'The later presence of the two ships in the ... area is purely coincidental,' a spokesman said.

Environmentalists say the ear-splitting sounds can disrupt the navigation systems of whales and dolphins.

Underwater seismic testing by the oil and gas industries has also been implicated.

However, the closest exploration work to Marion Bay last week was taking place in the waters between Tasmania and Victoria, 275 miles north.

The rugged Tasmanian coastline has one of the world's highest rates of whale beachings, and Marion Bay is a notorious blackspot.

In 1998 110 pilot whales died after beaching themselves in the same spot.

And in November 2004 115 pilot whales and bottle-nosed dolphins died in two strandings off nearby Maria Island, prompting the Australian government to set up a national database of such incidents.

Wildlife officials said last week that the latest deaths may have been caused by the animals becoming disoriented by the topography of the area, on the island's south-eastern coast.

Mark Pharaoh, of the Tasmanian Parks and Wildlife Service, said: 'The most common belief here is that since these strandings are so regular, it's basically difficult country for a whale to navigate in.' Another wildlife officer, Ingrid Albion, speculated that one confused whale might have led its entire pod on to the beach.

'Maybe they've come in close looking for food, maybe the tide's been a bit different,' she said.

'Only one of them has to get into trouble and make a wrong turn, and they'll actually call the rest of the pod to them.'Wildlife officials, helped by volunteers, managed to save 19 of the long-finned pilot whales.

Researchers at the University of Tasmania have suggested that beachings may be linked to a 10-year cycle of increased wind strengths over the Southern Ocean.

Changes in the earth's magnetic field and pursuit by killer whales are among other theories.

Animal protection groups have for years lobbied to restrict the use of sonar, saying the sound blasts disorient the sound-dependent creatures and cause bleeding from the eyes and ears.

In recent years, western governments have developed stealthier submarines the detection of which requires more powerful, low-frequency sonars.

"This is a hugely serious concern as these animals need sound to navigate, to find their food, to communicate and to mate," said Mr Simmonds.

A report by the International Whaling Commission's scientific committee last year concluded that the link between sonar and whale deaths was "very convincing and appears overwhelming".

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