The first warning bells about reefs were rung in 1990, when it seemed that global warming was killing the microscopic algae that corals depend on for their survival. Researchers later realized that other human activities might also be to blame; coastal development, overfishing, and pollution, for example, could have devastating effects. But their conclusions were always somewhat shaky because so few reefs had been evaluated, and even fewer had been monitored over long periods of time (Science, 25 July 1997, p. 491).

That's why in 1997, the International Year of the Reef, marine ecologist Gregor Hodgson of the University of California, Los Angeles (UCLA), and his colleagues recruited some 500 fishers and divers to take a systematic look at marine habitats (Science, 6 June 1997, p. 1494). The project, called Reef Check, grew and now covers 1500 reefs worldwide. At each site, volunteers and scientist-supervisors have estimated the ratio of live to dead coral, assessed the human impact, and counted key species of fish and shellfish. The analysis of this effort was published earlier this week.

The situation is grim, says Reef Check coordinator Jennifer Liebeler of UCLA. Significant declines were found in almost all the species they looked for; spiny lobsters, a long-spine black sea urchin called Diadema, groupers, parrotfish, wrasses, and even moray eels had often disappeared, some from more than three-fourths of the reefs surveyed. And only about half of the sites--most of them far away from human activities--had adequate amounts of hard corals, which build up to form reefs.

The report confirms that reefs "are in dire straights," says marine biologist Steve Gittings at the National Oceanic and Atmospheric Administration (NOAA), often as a result of human activity. On an up note, however, the report "helps continue to build political momentum" to get governments to pay attention and act, Gittings says.

--ELIZABETH PENNISI