Hugh Pickens writes writes "BBC reports that researchers have modeled the impact of rising temperatures on more than 600 species between 2001 and 2050 and concluded that fish body size may shrink in size by up to 24% because of global warming. The researchers built a model to see how fish would react to relatively small changes in temperatures at the bottom of the oceans using data from one of the higher emissions scenarios developed by the Intergovernmental Panel on Climate Change (IPCC) and found the resulting impacts on fish body size are unexpectedly large. "Rising temperatures directly increase the metabolic rate of the fish's body function," says lead author, Dr. William Cheung, from the University of British Columbia. "This leads to an increase in oxygen demand for normal body activities. So the fish will run out of oxygen for growth at a smaller body size." About half of this shrinkage is due to change in distribution and abundance, the remainder to changes in physiology and the tropical and intermediate latitudinal areas will be heavily impacted, with an average reduction of more than 20%. Dr Alan Baudron, from the University of Aberdeen, UK, has studied changes in the growth of haddock in the North Sea and believes rising temperatures could have negative implications for the yields of fisheries and could also seriously impact the ability of fish to reproduce, "Smaller individuals produce fewer and smaller eggs which could affect the reproductive potential of fish stocks and could potentially reduce their resilience to other factors such as fishing pressure and pollution.""