'Invasive' humans threaten U.S. coral reefs

0 Comments | USA TODAY, July, 2008 | by Dan Vergano

Half of all U.S. coral reefs, the center of marine life in the Pacific and Caribbean oceans, are either in poor or fair condition, a federal agency warns today.

The report by the National Oceanic and Atmospheric Administration places much of the blame on human activities and warns of further oceanwide decline.

Reefs closer to cities were found to suffer poorer health, damaged by trash, overfishing and pollution.

"Human impacts are making the big difference," says NOAA's Timothy Keeney, co-chair of the U.S. Coral Reef Task Force. "Humans are the most invasive species of all."

Coral reefs are living creatures made from the hardened shells of tiny polyps. They cover only 1% of the world's surface but play an outsize role in the oceans,...