SIMPSON, A.W.*; ECKELBARGER, K.J.; WATLING, L.; University of Maine – Darling Marine Center; same as above; same as above: Some Aspects of the Reproductive Biology of Paramuricea placomus (Octocorallia) from the Gulf of Maine

The cold-water octocoral, Paramuricea placomus (Linnaeus 1758), is endemic to the North Atlantic Ocean, occurring on both eastern and western sides of the basin. While the existence of this species has been known for hundreds of years, very little has been learned about its basic life history, including reproductive biology. Colonies of P. placomus have been reported as fisheries by-catch in U.S., Canadian, and European waters. The impact of fisheries on populations of this octocoral species are difficult to ascertain given the long history of commercial fishing in the North Atlantic and general lack of long-term data on by-catch. Insights into the ability of P. placomus populations to persist and recover from fisheries damage may be gained by an understanding of the reproductive abilities of this species. We sampled P. placomus colonies from the Gulf of Maine, U.S.A. and fixed tissues for histological examination of reproductive morphology. Our preliminary studies show that this species is gonochoristic. Male colonies contained spermaries with synchronously developing spermatocytes. A single male polyp may contain from 60-70 spermaries. Gonads develop along the mesentaries towards the base of the polyp, a pattern expected in female colonies which have not yet been studied.