Male reproductive success during spawning events of the octocoral Pseudopterogorgia elisabethae

Many sessile organisms rely on the transport of one or both types of gametes for reproductive success. While sperm limitation has been reported in some species, high fertilization success has been observed in others including the branching octocoral Pseudopterogorgia elisabethae. In such cases, males may compete for eggs to fertilize and the local dispersion of sperm will be an important component of male success. Individual reproductive success of 91 male P. elisabethae colonies found within a 400 m² area on San Salvador Island, Bahamas was examined based on microsatellite analysis of planulae collected from female colonies. Larvae which were brooded on the surface of 4 different females were collected during 2 separate spawning events. Males in the study area were sampled, and parentage was assessed using 5 microsatellite loci and the paternity assignment program CERVUS 3.0. Twenty-five percent of the larvae were assigned sires with ≥80% likelihood and 87 % of the planulae could have been sired by males within the study area. The success of males was not related to either distance to the female or to male colony size. On average, successful sperm only travelled 5.2 m and the success of individual males within the 400 m² study site was not significantly different from random expectations. Male P. elisabethae may follow spawning strategies that increase the likelihood of siring some planulae, spread success across multiple females and reduce variance in reproductive success.