MEPS 296:1-11 (2005)  -  doi:10.3354/meps296001

ABSTRACT: Marine reef fishes may spend a significant proportion of their daily activity budgets visiting cleaning stations. Nevertheless, the roles of ectoparasites and of interactions with cleaners in shaping patterns of diel activity in these fishes have been largely ignored, possibly because the importance of cleaning for the hosts remains controversial. In diurnal species, a peak in ectoparasite infestation exists at dawn, suggesting that higher rates of cleaner-seeking during this time should be beneficial to hosts. In this study, we quantified the diel pattern of visitations to cleaners, as well as other major activities, in female yellowtail damselfish Microspathodon chrysurus on a Barbadian fringing reef. Females of this species leave their territories near dawn at 3 d intervals to spawn on male territories. On non-spawning days, cleaning peaked at dawn, when fish spent >20% of their time with cleaners, and declined thereafter, averaging over 11% of the time budget during the entire day. Supplemental observations in Puerto Rico and the Virgin Islands also revealed dawn peaks in cleaner-seeking activity. Feeding and territory defense together occupied less than 3% of the time budget at dawn, and never seemed frequent enough to interfere with cleaning. On spawning days, 30% of females visited cleaners at male nests or while traveling back to their territories, and 24% visited cleaners on their own territories during revisitation trips before spawning was completed; nevertheless, they spent <¹/₃ as much time with cleaners as did non-spawning females. Reduced cleaner-seeking indicates that spawning competes with cleaner visitation in damselfish time budgets, producing a tradeoff between cleaning and reproduction. In the 30 min after spawning, females significantly increased their rate of interaction with cleaners, compared with the same time on non-spawning days, and regained about 68% of the missed time with cleaners; feeding and aggression did not differ between spawning and non-spawning females. Compensatory post-spawning visiting of cleaners supports the hypothesis that cleaning at dawn is important, probably because of negative consequences of the dawn peak in parasite loads.

KEY WORDS: Cleaning · Symbiosis · Diel activity cycles · Ectoparasite · Coral reef fish · Pomacentridae · Spawning