Fish cleaning behaviour in Noumea, New Caledonia

Abstract

Fish cleaning behaviour was quantified at Noumea, New Caledonia, for comparison with other studies, using a combination of cleaner fish diet analyses, client (host) parasite analyses, and observations of the cleaning rates of cleaners and client fish. Most (91%) of the items in the diet of the cleaner wrasse Labroides dimidiatus were parasitic gnathiid isopod larvae (165 ± 22 gnathiids per gut, mean ± s.e.) which made up most of the biomass (12.8 g). Gnathiids were common on the client fish Hemigymnus melapterus and Scolopsis bilineatus with 88% and 55% respectively infested with gnathiids.L. dimidiatus spent 26% of its time inspecting large numbers of fish (59.5 ± 5.1 fish per 15 min observation). H. melapterus was regularly cleaned by L. dimidiatus (2.5 ± 0.5 times for 17.5 ± 2.5 s per 30 min observation period). The cleaning rates of cleaners and clients are comparable to those found at Lizard and Heron Islands, Great Barrier Reef, Australia (1000 km apart), whereas the biomass of gnathiids was lower than at Lizard I. but higher than at Heron I., suggesting that the role of gnathiids in cleaning behaviour is widespread but variable.