Euro MPs have called for a ban on warships using submarine-seeking sonar devices because campaigners believe they may be killing dolphins and whales.

Scientists believe the Low Frequency Active Sonar (LFAS) submarine trackers are causing internal bleeding, deafness and lung damage in dolphins and depleting already-threatened fish stocks.

Scientists are reporting a link between LFAS and the deaths and beaching of marine mammals Caroline Lucas

The MEPs want a complete moratorium on LFAS use in European waters until a full environmental impact assessment is carried out, as required by the UN Convention on the Law of the Sea.

The MEPs say investigations have shown that strandings of marine mammals have become more commonplace following tests of the devices.

They claim more than 17 whales, dolphins and porpoises were beached in March 2000 following US tests near the Bahamas.

Environmental impact

Nine died following bleeding of the eyes, brain and lungs.

A cross-party group of more than 60 MEPs have signed a motion proposed by Green Euro MP Caroline Lucas supporting the ban on LFAS, which will be debated in Strasbourg on Thursday.

Lucas: The EU must act

Dr Lucas, MEP for the South East of England, said: "Scientists are reporting a link between LFAS and the deaths and beaching of marine mammals, some of which are legally protected endangered species.

"Fish stocks, already severely depleted around the UK, have also been affected by tests, according to the industry itself.

"The EU must act where Nato and member states have failed.

"LFAS technology must be subject to a rigorous environmental impact assessment to determine how many dolphins are dying and how much irreparable damage the sonar is doing to the marine environment.

"In the meantime, there must be no further testing or use of LFAS in European waters."

Disturbing

Nato members, including the UK, US and other states, have been developing LFAS submarine trackers for more than a decade.

They work by bouncing low frequency sounds at high volumes off the ocean floor, allowing operators to spot any large objects, such as submarines, and disrupt the signal.

The Green Party says the sounds used are up to 200 billion times louder than those which normally disturb marine mammals, causing internal bleeding, deafness and lung damage in dolphins and whales.

A Nato investigation conceded that a mass stranding of Curvier's Beaked Whales in Greece in 1996 could not have been caused naturally.

More recently, 15 beaked whales died after being washed up on the Canary Islands following military manoeuvres in the region of Nato's Mediterranean fleet.

Trawler nets

Post mortem examinations showed they had suffered brain legions and inner ear damage.

On Wednesday Lib Dem MP Matthew Taylor urged the UK Government to adopt a clear strategy to prevent dolphins from being caught in huge trawler fishing nets.

Since the beginning of this year the bodies of more than 40 dolphins have washed up on Devon and Cornwall beaches.