studies of fertilization rates(warner et al., in press), oceanographic regimes at aggregation and non-aggregation sites, and fate of fertilized to the information presented in this paper. the underwater video camera has proven a remarkable addition to tools available to the scientist to document spawning aggregations. the low light capability of such cameras allows recording in the dim light of sunset underwater. repeated examination of tapes allows extraction of information on numbers of fish, behavior, coloration and many other aspects of the dynamics of a spawning aggregation.