Farm fish are territorial and protect their algae gardens
ArteSub/Alamy
Fishes that tend stringy patches algae seem to protect branching corals from the worst effects of marine heat waves and help them recover after bleaching.
In 2019, reefs near the Polynesian island of Moorea in the South Pacific Ocean suffered their worst heat stress in 14 years. Due to about six weeks of unusually warm waters, the branching corals there have bleached en masse, during which time they lose the symbiotic algae that live there and provide them with most of their food.
In …