Ocean Warming Killing Europe's Porpoises

Posted on January 11, 2007

National Geographic reports that fish shortages induced by ocean warming are starving porpoises to death. The porpoises eat a fish called sand eels and there are not enough sand eels to keep the porpoises alive.

A Scottish team from Aberdeen University and the Scottish Agricultural College found that the number of harbor porpoises dying from starvation rose to 33 percent in 2002 and 2003-up from 5 percent in previous years.

The study, reported in the journal Biology Letters, was based on autopsies of beached harbor porpoises, Europe's smallest whale.

The porpoises rely heavily on sand eels, which make up to 80 percent of the mammals' diet in the spring, said Aberdeen University's Colin MacLeod, who led the study.

"We didn't really find other species of fish in their stomachs," he said. "If the sand eels aren't there, then there isn't any alternative food for them."

The article says the sand eels (apparently a fish and not an eel) are dying because the plankton they feed on are dying because of the warming temperatures in the North Sea. The article says the North Sea's temperature has climed 1.8 degrees Fahrenheit in the past 25 years.

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