Australian scientists have found that some fish act as “lawnmowers” and keep coral free from some unwanted algae and kelp. The best fish seem to be parrotfish and rabbit fish.
Higher sea temperatures are putting pressure on coral reefs which live within a relatively narrow temperature range. At higher temperatures the polyps expel the algae which symbiotically live with them and provide their nutrition. They may be able to recover, but if at the same time they are hit by an infestation of non-symbiotic algae or kelp, then their chances are significantly reduced. Hence the importance of the fish that graze on such unwanted algae or kelp.
The research was carried out on the Great Barrier Reef by scientists from James Cook University in Townsville.
You can read more from the BBC.
