A comparison of vertical distribution patterns and sampling methods for late stage reef fish larvae in the San Blas Islands, Caribbean Panama

This study compared three different methods to sample late-stage reef fish larvae around the field station of the Smithsonian Tropical Research Institute in the San Bias Islands, Caribbean Panama. Active sampling with a dip net around a kerosene and a fluorescent light was compared to sampling using an automated light trap. Catches among the three methods differed in taxonomic composition and timing. The families Gerriidae, Labrisomidae and Labridae dominated active netting. Gobiidae and Haemulidae dominated light trap catches. This suggests there is a difference in larval susceptibility to the different techniques, possibly behavioral. The varying timings of the catches for the different techniques support this theory. The vertical distribution of coral reef fish larvae was examined using light traps. This study showed there are clear patterns of vertical distribution in late stage reef fish larvae. Pomacentnds, Lutjanids and Gerrids dominated shallow traps while deep traps were dominated by catches of Apogonids, Gobiids and Acanthurids. These patterns are family dependent with only one or two species within a family demonstrating different behavior. These consistent patterns of vertical distribution dispel theories of larvae as passive particles in the water colunm. Specifically, this study implies that the late stage coral reef fish larvae are capable of directed swimming and actively maintain their position in the water column.