What Divers Should Know About Cleaner Shrimp

The term "cleaner shrimp" encompasses a fascinating group of decapod crustaceans often encountered by divers. These remarkable invertebrates engage in a critical cleaning symbiosis with client fish, diligently removing parasites from their bodies. This beneficial exchange not only frees the fish from irritating organisms but also provides a nutritional meal for the shrimp, which also consume mucus and debris from wounds, aiding in healing and reducing infection.

Divers frequently spot cleaner shrimp congregated at established "cleaning stations" on coral reefs, sometimes alongside cleaner fish and wrasse, all attending to client species. When a potential client fish approaches, several shrimp may perform a distinctive "rocking dance," a side-to-side movement believed to signal their readiness to clean. While many are visible during the day, some species, particularly those in the genus Urocaridella, favor cryptic habitats or caves on the reef and have even been observed cleaning sleeping fish after dark. At these stations, groups of up to 25 shrimp can be found living in close proximity, ready to service passing fish.