https://phys.org/news/2018-11-reef-fisheries-food-coral.html

But the results also showed fishing success was 'patchy' and more dependent on fewer species.

Around six million people fish on coral reefs. Each year their catch—estimated to be between 1.4 and 4.2 million tonnes—provides a critical source of food and income for many millions more. But climate change-driven coral bleaching events, caused by warming seas, are damaging coral habitat and depleting fish biodiversity, which has sparked fears that these vibrant ecosystems will no longer support productive fisheries.