CLEANER SHRIMP BEHAVIOR AND HUSBANDRY

 

 Skunk cleaner shrimp inspects the mouth of a complying anthias. Photo by Scott W. Michael.

We aquarists have long suggested that cleaner shrimps will remove cysts from fishes infected with Cryptocaryon irritans and may also ingest other parasites (e.g., trematode flatworms). Well, it turns out that science supports our anecdotal observations. Let's take a look at the scientific evidence. The first study of interest was conducted by Williams and Williams (1998) - they documented that Pederson's anemone shrimp (Periclimenes pedersoni) feeds on the larvae of parasitic isopods. Even more exciting was a study done by Becker and Grutter (2004). They analyzed cleaner shrimp gut contents as well as conducted some aquarium studies. They found that wild cleaner shrimps in the genus Urocaridella and Ancylomenes (formerly Periclimenes) holthuisi (known commonly as Holthuis' anemone shrimp) fed on parasitic crustaceans (e.g., isopods, copepods) and monogenean flatworms (Benedenia sp.). They also demonstrated that captive A. holthuisi reduced the parasitic load (in this case flatworms) by 74 % on captive surgeonfish. In the most recent study, Militz and Hutson (2015) documented that captive -held skunk cleaner shrimp (Lysmata amboinensis) will reduce infestations of a trematode in the genus Neobenedenia in groups of lyretail anthias (Pseudanthias squamipinnis). The shrimp reduced the infection success by the trematodes by half compared to controls that were not housed with shrimp. These beneficial crustaceans were found to eat both the flatworm's eggs and the larvae.

AN ODD-COUPLE

A pair of yellow shrimpgobies (Cryptocentrus cinctus) and an undescribed species of snapping shrimp on a sandy slope in the Raja Ampats. The gobies keep watch as the shrimp performs its maintenance duties. 

In the shrimpgoby-snapping (pistol) shrimp relationship both members benefit (mutualistic). The shrimp’s burrow provides a sanctuary for the otherwise vulnerable goby. In exchange, the gobies act as "seeing-eye" fish for their relatively poor-sighted crustacean partners (note: some crustacean experts have suggested that these shrimp actually see quite well, even so their visual acuity is not as good as that of the goby). As the shrimp keeps house or feeds just outside of the burrow, the goby will sit near the burrow’s entrance and “stand guard” (it will also feed and interact with conspecifics at this time as well). The crustacean moves freely in and out of its refuge, but when it leaves the burrow it keeps in contact with the vigilant goby. It does this by placing one of its antennae on the fish. When a predatory fish approaches, the goby will rapidly flick its tail, warning the shrimp of impending danger. If the goby flicks its tail once the shrimp may not respond, but if the goby executes a series of flicks the shrimp will retreat. If the predator comes within a critical distance, the goby will also dart into its hiding place.

We at Reef Tectonics love shrimpgobies and their snapping shrimp partners and would love to set-up this fantastic symbiotic relationship in your aquarium! 

© Scott W. Michael - Reef Tectonics