Publication Abstract

Sea trout in the 21st Century – threats and opportunities

A. Walker. Wild Trout Trust’s annual meeting, Greys of Alnwick, Alnwick, Northumbria, Saturday 12th April 2008

There have been significant improvements in water quality in most of the rivers of England and Wales; however, habitat damage continues to limit fishery performance. The effects of sub-lethal mixtures of chemicals, including some known to disrupt the endocrine systems of fish, are becoming apparent, and further research in this area is now being given high priority. Climate change is emerging as a major consideration in fisheries management. Understanding the effects of climate change on freshwater fisheries will be a major challenge over the next decades, and research is already underway. Increased urbanisation of waterways and a general increase in requirements for water and leisure industries also present problems, perhaps directly related to climate change. But, habitat improvements and controls on impacts, backed up by national and international legislative efforts, should continue to increase the opportunities for sustainable sea trout and trout stocks, and research continues to better understand these limiting factors, and to develop methods we can use to support these stocks. Also, we should not lose sight of the fact that the trout is a very adaptable and opportunistic species. This flexibility in life strategy allowed them to re-colonise British rivers after the last ice age. However, this adaptation might not proceed in the direction we want or expect. For example, as noted above, increased nutrients in freshwaters may enhance juvenile growth and productive capacity, leading to a reduction in the drive to migrate to the sea. For the moment, we are still trying to understand the mechanisms that influence this ‘choice’.