Colonization of Reef Fishes at Moorea Island, French Polynesia: Temporal and Spatial Variation of the Larval Flux

Abstract

Colonization by settlement-stage fishes of the lagoon at Moorea Island, French Polynesia, was studied with nets fixed at five sites on the outer reef crest around the island. The study occurred between 30 January and 29 March 1995 when an estimated 1.8 million settlement-stage fishes were collected in 164 samples, which contained 65 families and several new records for the biogeographical region. The results here concern only the largest taxa (length >1.5 cm), representing 46 families of reef fishes. Patterns of larval colonization varied strongly among families, although all displayed lunar cycles. The serranid Epinephelus merra occurred sporadically in catches but in very high abundances (1000 to 4000 individuals per sample). In contrast, some acanthurids such as Acanthurus triostegus were collected in most samples but catches never exceeded 100 individuals per sample. This methodology allows the colonization to be monitored and provides the first estimates of larval density at settlement. Future applications could include estimation of mortality rates during this critical phase of the life history.