Goby and Shrimp

Gobies and blennies are tiny fish only a few inches long with narrow bodies. They flit about actively on the reef and each fish is represented by hundreds of species. Gobies and blennies hide in holes and crevices in the reef and among intricate corals for protection.

Gobies’ behaviors are interesting in several ways. Certain gobies live in a close association with other animals. A unique relationship exists between several species of goby and the snapping shrimps (Alpheidae). The snapping shrimp digs elabor­ate burrows in the sand and lines the entrance with small pieces of shell and pebbles. However, the snapping shrimp has very weak vision. The goby shares the burrow with the shrimp and stands watch outside while the shrimp continually cleans out and maintains the burrow. The goby has far superior vision and sensi­tive lateral sense organs and can detect predators much sooner than can the shrimp. While the goby stands guard at the entrance to the burrow, the shrimp never goes far from the goby. Usually, the shrimp rests an antenna on the goby at the entrance to the burrow. When the goby first senses danger, it slaps the sand with its tail which the shrimp will sense through the pressure transmitted through the water and through its antenna touching the goby. The shrimp goes into the burrow and the goby soon follows if a predator moves closer. This partne­rship is a fascinating subject but is a difficult photo­graph to shoot. If the camera gets too near the goby to capture the detail of the shrimp in the background, the goby signals the shrimp to hide. This shot demands a great deal of patience since the photographer must move the camera toward the goby and shrimp with almost imperceptible movement.

Some species of gobies are cleaner gobies, just like cleaner shrimp. The gobies swim around and through the bodies, mouths and gills of fish and moray eels, removing debris and parasites. When the goby is allowed to enter the mouth, the fish or eel will keep their mouth open until the goby is finishes or the fish or eel grows impatient and shakes its open mouth to rid itself of the goby. You can easily identify a “cleaning station” by noticing fish in line awaiting their turn. Sharks also have their mouths “cleaned” in this fashion and will leave their jaws agape while the cleaner fish does its work.