Grazing fish must be protected to save Caribbean coral, scientists say

Coral reefs in the Caribbean are being smothered by algae and could soon be damaged beyond repair unless there is a campaign to protect a grazing fish that feeds on the aquatic plant, a study has found.

Scientists say much of the coral in the Caribbean risks being killed because algae is growing over it faster than it can be removed by grazers such as the sea urchin and parrotfish.

A study that attempts to chart the future decline of Caribbean coral has found that protecting parrotfish – which are prized for the dinner table – could be one of the best ways of trying to help coral reefs recover from several years of being smothered by expanding colonies of algae.

Coral reefs in the region have suffered from a range of environmental assaults over the past 30 years, from hurricanes and pollution to climate change.

The scientists found that reefs overgrown with algae would not recover if the original cause of the problem, such as pollution, was addressed because they had become permanently unhealthy.

Professor Peter Mumby, of the University of Exeter, said: "If we carry on the way we are reefs will change forever. This will be devastating for the Caribbean's rich marine environment and the livelihood of millions."

The study, published in the journal Nature, called for a ban on fish traps to protect parrotfish.