Goliath Grouper Reproduction in the Southeastern USA: Gonochoristic or Hermaphroditic?

Goliath Grouper is currently listed globally as “critically endangered” and is protected from both commercial and recreational fishing in U.S. waters. The current lack of data on reproduction and life history of Goliath Grouper makes it difficult to determine both the level of the stock’s recovery and if there is a level of harvest it can sustain in the future if conservation goals are to be achieved and maintained. Fundamentally, it is still not known whether goliath grouper are gonochoristic or hermaphroditic. Our current research indicates that Goliath Grouper are hermaphroditic, with gonadal histology indicating a high proportion (16%) of fish with both ovarian and testicular tissue. However, some fish (4%) had relatively equal amounts of both male and female tissue, and had oocytes that were in all stages of development, including later vitellogenic stages, which indicated that they were spawning capable. These fish also had male spermatogenic tissue interspersed throughout the gonad, indicating that they were developing or mature males. Having an accurate picture of the reproductive life style of Goliath Grouper is critical to assessing its recovery and future management in any re-established fishery.