As the concentration of carbon dioxide continues to increase in the atmosphere, more carbon dioxide, in turn, is taken up by the ocean. This increased dissolved carbon dioxide causes a steady decline in oceanic pH, termed ocean acidification. Both scientists and policy makers fear that this process is causing long term damage to marine life and fisheries.

In a project co-funded by the UK Natural Environment Research Council, Defra and DECC, and led by Professor Kevin J Flynn of CSAR, scientists at Swansea, together with colleagues from the Universities of Exeter and Strathclyde, studied whether changes in ocean pH, together with temperature, were detrimental to young sea bass. To test this, sea bass were raised from hatch under different combinations of elevated temperature and increased carbon dioxide for up to 10 weeks.

Sea bass appear to be resilient to near-future ocean conditions in terms of growth, development and survival. However, juvenile fish showed a decreased athletic ability (termed aerobic scope) when raised under more acidic conditions. Whether this physiological change continues into adult fish is an area of concern and something the study’s main author, Dr. Edward Pope, is now exploring.

The study was funded by the UK Ocean Acidification Research Programme and is published online in Biogeosciences, an Interactive Open Access Journal of the European Geosciences Union: http://www.biogeosciences.net/11/2519/2014/bg-11-2519-2014.html