MEPS 193:191-199 (2000)  -  doi:10.3354/meps193191

ABSTRACT: We compared time spent at cleaning stations and ectoparasite loads for adult and sub-adult yellowtail damselfish Microspathodon chrysurus on nearshore fringing reefs in Barbados. In a preliminary study on 2 reefs in summer 1997, both time spent at cleaning stations and frequency of chafing were inversely correlated with distance from shore. A subsequent study in spring 1998 of fish at the shore- and seaward ends of 8 reefs revealed a strong sex by habitat association, with males predominating at the seaward end and females predominating at the shore end. Females and combined fish at the shore end of reefs had access to fewer cleaners but spent more time visiting cleaners than males and combined fish at the seaward end of reefs. Chafing showed the same relative difference but was not significant. Ectoparasites included gnathiid isopod larvae, parasitic copepods, and dactylogyrid monogeneans. Total crustacean loads, but not monogenean loads, increased with body size. With the effects of body size statistically removed, crustacean loads were significantly higher in females and fish at the shore end of reefs. Monogeneans showed a similar but marginally non-significant trend. These data indicate an association between ectoparasite loads and amount of time spent at cleaners, and thus appear consistent with adaptive, mutualistic hypotheses of client-cleaner interactions. However, the causal relationships between them, habitat, and sex remain to be determined.

KEY WORDS: Pomacentridae · Coral reef fish · Ectoparasites · Cleaning symbiosis · Caribbean · Copepoda · Monogenea · Gnathiidae