EFFECTS OF SELECTIVE SETTLEMENT AND OF AGGRESSION BY RESIDENTS ON DISTRIBUTION OF YOUNG RECRUITS OF 2 TROPICAL DAMSELFISHES

The reef fishes that settled on an array of experimental corals at Lizard Island, Queensland, Australia, were counted during a pulse of recruitment in December 1986. Neither Pomacentrus sp. nor P. amboinensis showed any evidence that harassment by resident Dascyllus aruanus caused a decrease in persistence during the first day after settlement. Larval Pomacentrus sp. settled selectively on corals without resident D. aruanus. The results for P. amboinensis were ambiguous. Settlers of both species positioned themselves closer to the sand on corals with resident D. aruanus than on unoccupied corals. This could reduce access to planktonic food and increase the risk of predation. Adult aggression may be less important and active selection of settlement sites by larvae may be more important to the distribution of recruits than is suggested by the literature. The presence or absence of particular species should be included among the cues that larval reef fishes use to choose settlement sites. © 1990 Springer-Verlag.