A Recipe For Reef Recovery

Coral reefs around the world are suffering under the pressures of overfishing, coastal development, pollution and climate change, with some 75% reported to be in decline. Fishing is the main cause of reef decline around the world, but reef-based fisheries provide a vital source of protein to over a billion people - something they cannot afford to loose. So how can we help reefs recover while maintaining this vital food supply?

A new study, published in Nature, shows the answer lies in leaving the right fish on the reef. Those that eat algae are the most important to keeping reefs running, as, if not kept in check, algae can quickly outcompete the coral, leading to rapid reef degradation. Such fish include grazers like damselfish and rabbitfish, and browsers like surgeonfish and parrotfish.

To put reef ecosystems back on track, we need to restore key fish populations, boosting those that play a big role on the reef. "Reef fish play a range of important roles in the functioning of coral reef ecosystems, for example by grazing algae and controlling coral-eating invertebrates, that help to maintain the ecosystem as a whole," says study co-author Nick Graham.

To put overfished reefs on the road to recovery, the answer lies in restoring populations of algae-eating fish. And for those with less fishing pressure, careful management is the key: knowing which fish to catch, and which to let off the hook.

Reference

MacNeil, M. A., Graham, N. A., Cinner, J. E., Wilson, S. K., Williams, I. D., Maina, J., ... & McClanahan, T. R. Recovery potential of the world's coral reef fishes. Nature, 520, 341-344 (2015)