Coral reefs-Fish pee for Media

Images above courtesy University of Washington Fish Pee Corals Flickr album.

Researchers from the University of Washington have discovered one key to successful coral reefs: that big fish are present. Predator fish, the larger fish, provide needed phosphorus and nitrogen via their urine and excreted through their gills as ammonium. Data showed that carnivorous fish provided more phosphorus than the smaller herbivore fish (they peed more).

Lead author of the study, Jacob Allgeier, spent four years analyzing fish pee measuring the amount of nutrients in bags of water that contained different fish. The amount of nutrients corresponded with the actual size of the fish, and what the fish ate.

From Jacob Allgeier, postdoctoral researcher from the School of Aquatic and Fishery Sciences at the University of Washington:

“Fish hold a large proportion, if not most of the nutrients in a coral reef in their tissue, and they’re also in charge of recycling them. If you take the big fish out, you’re removing all of those nutrients from the ecosystem.”

Curbing the big predator overfishing could help dying coral reefs to recover.

The full article and research is found at the University of Washington.

John’s motto is ‘release it unharmed or do it justice on the plate.’ Executive Chef, photographer, and surfer, John photographs ocean marine life when he’s out fishing, and creates masterpieces in the kitchen with what he keeps on deck. His photo works have been used in OEHHA Fish Advisories, National Geographic presentations, and nonprofit marine life groups. When he’s not fishing, he’s making great BBQ. Visit him at, and send him a message using the contact form using the link above.