Noise to save porpoises' lives

Scientists are trying to discover what kind of noise annoys a porpoise, in an attempt to save the threatened mammal.

The underwater acoustics group at Loughborough University, in Leicestershire, hope to perfect an electronic "pinger" which will send porpoises swimming away from death in fishermen's nets. Chief experimental officer David Goodson said he hopes to produce a small waterproof box which can be sold to fishing fleets worldwide. His team's efforts come as figures for deaths of the animals have raised fears among some conservationists that one important species, harbour porpoises (above), could disappear around much of Britain and Ireland.

Paul Jepson of the Institute of Zoology in London said the figures were based on a survey by Cornwall Wildlife Trust, which put volunteers on Irish and Cornish fishing boats and counted 43 dead porpoises in nets. Calculations from that suggested 2,300 would be found across the whole Celtic Sea, or about 6 per cent of the estimated area population of harbour porpoises, he said.