Warning on the oceans

An article in the Post on the seriousness of global warming and development for ocean species.

Now, some suspect the world is on the cusp of what Ellen K. Pikitch, executive director of the Pew Institute for Ocean Science, calls "a gathering wave of ocean extinctions." Dozens of biologists believe the seas have reached a tipping point, with scores of species of ocean-dwelling fish, birds and mammals edging toward extinction. In the past 300 years, researchers have documented the global extinction of just 21 marine species -- and 16 have occurred since 1972.

Since the 1700s, another 112 species have died out in particular regions, and that trend, too, has accelerated since the mid-1960s: Nearly two dozen shark species are close to disappearing, according to the World Conservation Union, an international coalition of government and advocacy groups.

"It's been a slow-motion disaster," said Boris Worm, a professor at Canada's Dalhousie University, whose 2003 study that found that 90 percent of the top predator fish have vanished from the oceans. "It's silent and invisible. People don't imagine this. It hasn't captured our imagination, like the rain forest."