All-You-Can-Eat Algae Buffet

Food can be a big incentive in animal behaviour, including fish. Reef fish evade predators such as sharks by hiding in coral reefs, but they venture out at times to eat the algal blooms that are caused by pollution and which threaten coral reefs worldwide. It’s a risky business, however, as emerging from safety means they run the risk of being eaten themselves. The fish can weigh up the costs and benefits, though, a study has found. When scientists placed ‘buffets’ of algae at locations off the island of Mo’orea in French Polynesia, the fish would ignore the dangers if the amount of food on offer was generous enough. The hope is that if overfishing is prevented in coral reefs, the fish can counteract at least some of the damage caused by algal blooms.