Changing patterns of distribution and migration of Westcountry fish stocks are similar to changes being witnessed off South Eastern Australia, suggests a report.

While 20 years ago UK bass stocks were almost exclusive along the shores of South Wales, the Westcountry and the Channel Isles, bass are now commonly caught around Scotland, and many scientists and commercial fishermen point to climate change as the reason. Scientists in South East Australia report significant changes in the distribution of their coastal fish species, equally suggesting climate change as a main factor.

Forty-three species representing 30 per cent of the inshore fish families occurring in the region have exhibited shifts thought to be climate-related; these include warm temperate surf-zone species such as silver drummer and rock blackfish that are breeding and have become more abundant. Range increases in snapper and rock flathead have also been recorded, said the report. There is also a greater abundance of warm water tunas and billfishes, and occasional visits from Queensland groper and tiger sharks.

"Furthermore, up to 19 species, or five per cent of Tasmanian coastal fish fauna have undergone serious declines or are possibly extinct locally," says the Curator of the Australian National Fish Collection, Dr Peter Last.

"At the same time many warm temperate species have moved in and colonised the cool temperate Tasmanian region. Shifts in the distribution of marine animals in response to climate change can be detrimental to some species. The problem is that in southern Tasmania, shallow cold water species have nowhere to escape warmer conditions."