Cornwall’s famous dolphin population is being wiped out by fishing boats, say scientists investigating the discovery of 1,000 dead animals on British and French beaches this spring.

They found that almost all the dolphins bore fatal injuries inflicted by fishing gear and estimate that the bodies of another 3,000 did not reach shore — a total death toll of 4,000.

The seas off Cornwall are home to one of Europe’s biggest populations of dolphin, which are renowned for putting on displays off tourist beaches and joining surfers riding the waves. They roam from the southern Irish Sea to the Bay of Biscay.

However, scientists say deaths caused by fishing gear could wipe the creatures out, with at least 100,000 killed over the past 20 years