Larval Supply and Patterns of Recruitment for Two Caribbean Reef fishes Stegastes partitrus

Abstract

To examine the relative roles of physical and biological processes involved in the recruitment of reef fishes, temporal and spatial patterns of supply and recruitment were measured for two fishes, Stegastes partitus (Poey) (Pomacentridae) and Acanthurus bahianus Castelnau (Acanthuridae), recruiting to Barbados, West Indies. Nightly light-trap collections of late-stage larvae were compared with patterns of juvenile recruitment. Otolith records provided estimates of larval duration and post- settlement age. Temporal patterns of larval supply were similar for both species: abundances peaked during the third-quarter moon. However, spatial patterns of larval supply varied between species: during large recruitment events, S. partitus larvae were more abundant in the south, A. bahianus in the north, suggesting that larval supply was not simply the result of passive transport. Patterns of supply were subsequently maintained (S. partitus) or modified (A. bahianus) by juveniles. In general, densities of juvenile S. partitus were evenly distributed along the coast; however, during major events, spatial patterns of recruitment reflected patterns of larval supply. In contrast, densities of juvenile A. bahianus were directly opposite patterns of larval supply, suggesting that for some species, postsettlement processes such as habitat selection may be more influential in creating spatial patterns of recruitment.