Parrotfish eat coral and then poop it out, resulting in white sandy beaches that we love to walk and lay on. The white sand reflects sunlight a lot better, resulting in cooler beaches. When parrotfish are ready to sleep at night, they secrete a mucus from special glands in their gills and create a "cocoon". This can help them hide their scent from predators at night and also prevent parasites from latching on. Parrotfish eat coral and then poop it out, resulting in white sandy beaches that we love to walk and lay on. The white sand reflects sunlight a lot better, resulting in cooler beaches. When parrotfish are ready to sleep at night, they secrete a mucus from special glands in their gills and create a "cocoon". This can help them hide their scent from predators at night and also prevent parasites from latching on.