Estimating fertilization success in marine benthic invertebrates: a case study with the tropical sea star Oreaster reticulatus

Several factors can influence fertilization success, and for marine broadcast spawners, the main constraint is rapid dilution of gametes. Because the measurement of fertilization success in the field is logistically difficult, theoretical models have been used as an alternative method of estimation. We tested the predictive ability of the existing models (time-averaged diffusion model in conjunction with a fertilization kinetics model) by making direct comparisons between empirical and corresponding predicted rates of fertilization in the tropical sea star Oreaster reticulatus. Using induced spawnings, we measured in situ fertilization in field experiments at 4 sites on sand bottoms and seagrass beds in the Bahamas.