Once again, scientists forewarn us of the consequences of global warming unless greenhouse gases emissions cease. By 2050, they predict that more than 600 species of fish will shrink in terms of maximum body weight by 14% to 24% if global temperatures persist to ascend.
Researchers at the University of British Columbia, led by Dr. William Cheung, came up with a model based from Intergovernmental Panel for Climate Change, predicting the impact of warming waters on marine life. The model used albeit small changes in temperature, a large impact on fishes’ body sizes resulted, with the largest reductions on fishes thriving in Indian and Atlantic Oceans.
The trend stems from the oxygen levels in waters. Warmer waters would increase the body temperatures of fishes, increasing their metabolic rate, which in turn will increase oxygen demand, which ultimately decreases oxygen levels. Fishes will consequently run out of oxygen for their growth.
When the model was compared with real data, those of North Atlantic cod and haddock, it was found out that the shrinkages were much higher than those projected by the model.
Aside from size changes, scientists also believe that most of the fish will be migrating towards cooler parts of the earth, north and south poles, at a projected rate of 36 km per decade. Fisheries may also have lower yields as smaller sizes of fish may have reduced reproduction capabilities and resilience to other environmental hazards.