Cleaner-client interactions on a Caribbean reef: influence of correlates of parasitism

We investigated the influence of known correlates of parasitism, namely fis h density, body size and social behaviour, on three highly variable aspects of the interactions between cleaning gobies (Elacatinus spp.) and their cl ients, on a Barbadian coral reef. We specifically considered (1) variabilit y in client visit rate to cleaning stations, (2) cleaning goby preference f or specific clients and (3) variation in the time spent cleaning by cleaner s. Using phylogenetically independent contrasts, we found that client speci es that were abundant on the reef visited cleaning stations more often than rarer client species. This could be due to the positive relationship betwe en ectoparasite load and client density, or alternatively may simply reflec t the frequency of contact between cleaners and clients. Cleaning gobies sp ent more time cleaning large-bodied clients, which usually have higher ecto parasite loads, although cleaning goby preference for clients was influence d by none of the correlates of client parasitism. Overall, factors assumed to correlate with ectoparasite load had a limited influence on the variabil ity observed in the interactions between cleaning gobies and their clients.