Dolphin charities blame Navy for Cornish beachings

As the bodies of 26 common dolphins were recovered from the Cornish coastline last week, marine mammal experts and conservationists struggled to understand the incident.

More than 70 dolphins in danger of beaching themselves were ushered back out to sea by would-be rescuers last Monday but more than a third of them eventually died, making it the biggest stranding in British waters for 25 years.

The Royal Navy has been blamed by some environmental groups who claim they have been warning for years that military sonar systems can wreak havoc with the senses of whales and dolphins. The Ministry of Defence denies this, but it has now emerged that the Navy held a large exercise in nearby waters just days before the dolphins beached themselves on the banks of the Percuil river, near Portscatho.

Several ships from the British, Dutch and German fleets were involved, along with a Merlin helicopter equipped with powerful mid-frequency sonar of the type associated with previous deaths of marine mammals around the world. The exercises took place 50 miles south of where the strandings took place.

Liz Sandeman, director of Marine Connection, a London dolphin charity, said: "The Navy's use of active sonar near the stranding site heightens our concern that sonar played a role in killing these animals. We already know that exposure to high-intensity sonar can kill marine mammals. A full, transparent investigation is needed to get to the bottom of it."

David Nicoll, a helmsman with the Royal National Lifeboat Institution, was one of the first to arrive at Porth Creek, off Falmouth Bay, last week where many of the dolphins died. He said it was "a horrible scene of carnage with bodies everywhere". Under the glare of the sun, the dolphins died slowly, their body weight crushing their lungs.

Sarah Dolman, of the Whale and Dolphin Conservation Society, said: "The continued use of military sonar presents a clear and present danger to marine life. Unless more safeguards are taken we can expect more mass strandings."

However, an MoD spokesman said: "It is highly unlikely that the activities could have been responsible for the disorientation of the mammals."

The UK cetacean stranding investigation programme is conducting post-mortem examinations and laboratory tests. Rob Deaville, its manager, said: "We are considering all possible causes of death. This will take several weeks at least."

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