Aquaculture 2022

February 28 - March 4, 2022

San Diego, California

STOCK ENHANCEMENT EFFORTS OF SOUTHERN FLOUNDER Paralichthys lethostigma IN ALABAMA COASTAL WATERS

Max J. Westendorf* and John Mareska

 Claude Peteet Mariculture Center

 Alabama Department of Conservation and Natural Res., Marine Resources Div.

 Gulf Shores, AL 36542

 Maxwell.westendorf@dcnr.alabama.gov



 In Coastal Alabama, and throughout the Gulf of Mexico, Southern Flounder (Paralichthys lethostigma ) is  and has been a popular recreational and commercial species. Recent commercial and recreational landings indicate lower abundance of Southern Flounder in Alabama coastal waters – an observation also common in anecdotal reports from fishermen.  A stock assessment on of the species was performed in 2018.  The results indicated a decline in overall abundance due to an extended period of low recruitment.  In addition, the results showed the stock is was not currently overfished, but experiencing overfishing which would result in an overfished condition in the future if management changes were not implemented.

 One of the suggested tools for improving management of Southern Flounder was use of a stock enhancement program.  The Alabama Department of Conservation and Natural Resources, Marine Resources Division maintains the Claude Peteet Mariculture Center (CPMC) located in Gulf Shores, Alabama .  The CPMC facilities include  a 23,000-square foot building containing rooms for broodstock maturation and spawning, algae  and  live food production, egg incubation, larval rearing, and juvenile holding.  Complementary infrastructure includes thirty-five - 0.2-acre  PVC  lined ponds, a greenhouse complex containing re-circulating tank systems, and two seawater pipelines (brackish and full-strength sea water). 

 Southern Flounder broodstock were acquired locally beginning in 2018 and held in temperature and photoperiod-controlled tanks at CPMC.   Utilizing Ovaplant®, an experimental hormone for this species, an estimated 12,236 fingerlings were released to Alabama inshore waters in 2020, and 34,591 fingerlings were released in 2021.  In 2021, investigations began at CPMC attempting to identify and refine cryopreservation techniques for Southern Flounder milt to improve fertilization success and gene diversity.