Coral Reefs Rebound from Damage if Protected

This encouraging report about coral reefs was talked about on ArsTechnica.

Basically reefs bounce back if they are protected:

The study examined ten different reef sites in and around the Bahamas over the course of two and a half years. The reefs had seen damage both from bleaching and from hurricane Frances in the summer of 2004. At the beginning of the observation period, the reefs had, on average, seven percent coral coverage. At the end, two and a half years later, the reefs in marine reserve had coral coverage increase by 19 percent, when initial distribution was taken into account. The areas not protected as part of a reserve showed no statistically significant recovery.

The key is reducing the amount of fishing that goes on because the fish actually help keep down the algae population which, if left unchecked, will quickly overwhelm a reef:

Their work shows, for the first time, that reducing the amount of human interference, mainly fishing, can help nature regain lost ground. By limiting the amount of parrotfish taken, the reserves gave these natural herbivores the chance to keep the local seaweed population under check, which gave the reefs the breathing room they needed to bounce back.

It is true that Parrotfish eat coral but they also graze on the algae that grows on the the reef (as opposed to the algae that grows in the reef which has a symbiotic relationship with the coral). The coral that the Parrotfish eat gets excreted as part of their normal digestive process as sand which eventually makes it to a beach somewhere. So next time you are walking across a beautiful white beach spare a moment to remember where the sand came from.