Dr. Hans-Otto Portner has revealed some rather disturbing findings from his study of climate influences on ecosystems. Some fish species that he studied in the North and Baltic Seas were found to have experienced a reduction in abundance, resulting in their geographical distribution range being shifted towards colder waters. A direct correlation between increasing global temperatures and decreasing fish populations has been shown. The Atlantic cod, for example, were once common in the North Sea, but have dwindled in numbers and fled further north after their natural waters have already gone up +1.1 degree Celsius.

�This was the first example where we could relate a physiological disturbance observed in the fish with physiological processes behind what we see in the ecosystem, so it�s a step forward to a cause-and-effect understanding about how climate acts on marine fishes in their ecosystem�, said Dr. Portner. The study concludes that the phenomenon is not isolated to the North Sea, but occurring in oceans around the world. Pressure is especially high on species which are commercially viable. Portner’s research adds credibility to Boris Worm’s study on biodiversity in the oceans, which concluded that wild fish have until 2050 before their populations can no longer sustain themselves.

source