SKIRMISHER

Over the past two or three decades, scientists have noticed with growing alarm that vast stretches of coastal waters are turning into dead zones — patches of seabed so depleted of oxygen that few creatures, if any, can survive there. In 2004, the United Nations Environment Program (UNEP) took stock of the phenomenon — which is caused in large part by agricultural runoff — and pronounced it one of the biggest environmental problems of the 21st century. Two years later it noted that the number of identified dead zones, some of which cover thousands of square miles, had climbed from 150 to 200.

Predictably, things have gotten worse since then. Robert Diaz, an ecologist at the College of William and Mary in Virginia who helped UNEP with its numbers, reports in the current issue of the journal Science that today there are more than 400 known dead zones along coastlines around the world, covering roughly 95,000 sq. mi. of seabed. Some of the dead zones that Diaz and his Swedish co-author identify in their review have been around for some time, but have only recently been studied. Many others appear to be new. About 8% of them, mainly those in the Baltic and North seas, persist throughout the year, says Diaz; half, including one the size of New Jersey in the Gulf of Mexico, form mainly seasonally, typically beginning in summer after the spring thaw and receding in the fall. Overall, the researchers found that the number of new dead zones has grown exponentially over the past four decades.

That’s bad news for fish — and for the people who eat them.

link

{Photo: Malaysian mermaid carcass}

Stumble it!