Southwest May Lose Dolphins And Whales - 20/07/2007

SCIENTISTS believe that the dolphin population in the southwest is under threat after a recent report found the number of sightings of certain species to have fallen dramatically since 1990.
Worryingly, it also reveals that the number of cetaceans – whales, dolphins and porpoises – washing up dead on the shores of the southwest is rising.
The report, by Marine Connection and The Wildlife Trusts, highlights the southwest as one of the UK's four dolphin hotspots, where up to 14 species of cetaceans can be seen.
Although the report shows that overall sightings are increasing, it believes this is due to a heightened awareness of the importance of reporting them. It reveals that sightings of the UK's best-known species of dolphin, the bottlenose, have fallen from a peak of 340 in 1992 to an average of 120 a year since 2000. It also reports more than 2,000 cases of cetaceans washing up dead between 1990 and 2004.
Almost 95 per cent of common dolphin strandings in the UK occurred in the southwest, mainly between December and March. This coincides with the bass pair-trawling season – known to catch large numbers of cetaceans – the report adds. According to Marine Connection, entanglement in fishing gear is the number-one cause of death in stranded cetaceans that have been subject to a post mortem. The Wildlife Trusts claim that the bass-trawling fishery has killed an estimated 39,000 common dolphins in the last 15 years, based on the assumption that only one in 10 are washed up on the shore.
The report highlights measures that have been taken to reduce by-catch fishing, entanglement or accidental capture, of cetaceans in fishing gear. These include modifying fishing gear and the use of 'pingers' – devices that emit a sound to deter cetaceans – but it says that these measures can be costly. It also acknowledges the UK ban on bass pair trawling within 12 nautical miles of the coast, introduced in January 2005. However, this only applies to UK vessels.
In closing, the report suggests that fishing restrictions should be introduced at times when cetaceans are vulnerable to high levels of by-catch. It also says that the southwest could lose its cetaceans altogether unless there is an urgent study into the activity of both cetaceans and fishing vessels.