Look, they're only dolphins ... aren't we all over-reacting?

The Royal Navy was conducting a live firing exercise and using sonar in the hours before dozens of dolphins were left beached on a Cornish creek, it confirmed last night.

At least 26 dolphins perished or had to be put down after Sunday’s stranding, which was Britain’s largest for 25 years.

An even greater tragedy was prevented as other dolphins attracted by the distress calls of their beached companions attempted to go to their aid. Around 40 dolphins managed to escape.

The Ministry of Defence admitted it had been conducting exercises involving surface ships and submarines in Falmouth Bay. A spokesman said that a survey vessel was using “short-range side-scan sonar” at the time adding that this was “extremely unlikely” to have affected the dolphins.

The Maritime and Coastguard Agency (MCA) said they were issuing warnings to shipping about “extensive submarine activity” from Sunday morning to midday Monday.

British Divers Marine Life Rescue (BDMLR), who coordinated the rescue of several dolphins, said they had received reports from the public that an explosion took place at sea over the weekend.

The MoD said they are not aware of any explosion.

Other theories for the stranding are that the dolphins were chasing a shoal of mackerel when they became trapped in the tidal creek near Falmouth, that they were fleeing a predator such as a killer whale or that they had been disturbed by the sound of sonar from a submarine or warship.

Post-mortem tests on the dolphins are continuing and so far preliminary findings have failed to show an obvious reason why they died or became stranded.

The tests revealed the animals were well fed and there were no obvious signs of disease or poisoning.

BDMLR chairman Alan Knight, who said all the dead animals were common dolphins, added that in 20 years he has not seen anything like it before.

He said the strandings were in four separate locations and he believed the animals were panicked by an underwater disturbance.

“I have never heard of anything like this, certainly not in the UK and possibly not anywhere,” he said.

“We can find no conclusive evidence as to why the stranding took place or why they stranded in such numbers at different locations.

“My own personal conclusion is that there was some sort of disturbance that has caused the animals to panic.”

Mr Knight said they were investigating shipping movements in the area as well as any mining or military exercises.

One of the rescuers, Dave Nicoll of the RNLI, said he and his two volunteer crew did their best to help the stranded animals.

“I can’t say I’ve seen such a terrible scene as that which confronted us when we first arrived in the creek with the lifeboat.

“It was horrific, but my two volunteer colleagues, Tom Bird and Joe Sabien, were brilliant.

“They very carefully got into the water to assist the dolphins that were still alive and the results were successful.”

An MoD spokesman also said they had a survey vessel using “short-range side-scan sonar” for sea bed mapping trials but added this was “extremely unlikely” to have affected the dolphins.

The spokesman also confirmed they had carried out live firing exercises off Eddystone Light, south of Plymouth on Friday.

He said: “A survey vessel was conducting trials using a high-definition, short-range side-scan sonar for sea bed mapping.approximately 12 nautical miles off the coast of Falmouth at the time of the incident.

“It is considered extremely unlikely that this operation could have affected the mammals in any way.

“We take our environmental responsibilities very seriously and always carry out an environmental impact assessment before putting energy in the water.”

The Natural History Museum said its zoologists from the National Whale Stranding Scheme were working with vets from the Zoological Society of London to discover why the dolphins stranded.

It said marine strandings occurred for a number of reasons, including sickness, disorientation, natural mortality, extreme weather conditions or injury.

Zoologist Liz Evans-Jones said: “Whales and dolphins strand themselves for a number of reasons and we’re not sure yet what happened with these dolphins.”

“There has not been a mass stranding in Cornwall since November 2001, when 16 common dolphins were spotted floating dead out to sea just off Looe.”

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