Plant-grazing Fish Boost Resilience Of Coral Reefs

By using cages to experimentally control the access of fish to coral reefs, researchers have assessed the role of fish "grazing" in the ability of reefs to successfully recover from potentially devastating coral-bleaching events related to rises in ocean temperatures. The findings, reported by a group led by Terry Hughes of James Cook University in Australia, will appear in Current Biology online on February 8th. Pollution and overfishing have for some time been major threats to the health of coral-reef ecosystems, but additional environmental stress caused by warming of ocean waters has recently become a key factor in coral-reef stability. The importance of this kind of stress is illustrated by the massive coral-bleaching event of 1997-1998, which impacted 16% of the world's reefs and was particularly damaging in regions of the Pacific and Indian Oceans...