Parasite removal rates by the cleaner wrasse Labroides dimidiatus

Abstract

The rate at which parasites (mainly gnathiid isopod larvae) were removed from fish by the cleaner wrasse Labroides dimidiatus was investigated. To examine the effect of this parasite removal on the parasites of fish, the number of parasites removed per individual host fish Hemigyrnnus melapterus per day was estimated and compared to the infection, rate and abundance of gnathiids on H. melapterus. The study was conducted at Lizard Island, Great Barrier Reef, Australia, using a comblnation of observations of the feeding rates of cleaners, estimates of how much time lndividual hosts spend being cleaned, cleaner fish stomach content analyses, and a gnathiid manipulation experiment. The frequency and duration of inspection by L. dimidiatus were measured to provide an estimate of the feeding rate. lndividual L. dimidiatus spent on average 256 + 11 (SE) min d-' inspecting 2297 + 83 fish.