Interspecific interactions among the wrasse, Labroides dimidiatus, and coral reef fishes.
Cleaner wrasses are noted for their distinctive cleaning behavior of other fish in reef environments. In this research I consider two aspects of the host cleaner relationship using fish communities at two islands on the Great Barrier Reef, Australia. First, I analyzed the frequency of initiation of cleaning bouts by cleaners relative to host initiations to determine whether the relationship is parasitic or mutualistic. There was considerable variation among individual cleaners in their tendency to initiate cleaning bouts. Overall, cleaner wrasses at Orpheus Island initiated more bouts relative to hosts than did cleaners at Lizard Island, where the frequency of initiations was more similar between cleaners and hosts. This suggests that ecological differences between the two islands may influence the parasitic or mutualistic nature of this relationship. Second, since foraging among widely scattered coral reef fish provides a model system in which to test optimal foraging theory, I asked whether cleaners behave optimally once they initiate a cleaning interaction. I considered the duration of cleaning interactions terminated by the cleaner relative to the time spent searching for a new host. Cleaners at the two islands did not differ in elapsed time to next host but were found to spend more time cleaning individual hosts at Lizard Island. The relationship between duration of cleaning bout and time spent searching for the next host will be discussed.
Cleaner Wrase Inspecting a Coral Trout