Intense fishing pressure by recreational and commercial fishing contributed to the population declines of goliath grouper.  When large numbers of otherwise randomly-dispersed fish become concentrated in aggregations in predictable areas and times, they are extremely vulnerable to overexploitation.   Such overexploitation has resulted from fishing on spawning aggregations of Nassau grouper Epinephelus striatus, gag Mycteroperca microlepis and other grouper populations throughout the world.  Fishing on spawning aggregations removes  reproductive individuals, usually the largest fish in the population.  Because this particular fishery concentrated on fish 9 years old or older, most individuals were captured not long after reaching maturity (since they mature at 7 or 8 years old) and thus had few or no opportunities to spawn.   Their slow growth, longevity, and large size at sexual maturation make them especially susceptible to overfishing. Indeed, the genetic diversity in the population was likely affected when the fishing mortality rate exceded the natural mortality rate.

    Threats to Healthy Mangrove Habitat

Juvenile goliath grouper recruit to mangrove habitat throughout their range.  This habitat in Florida has declined since the early 1900s due to channelization to redirect freshwater flow from the Everglades, mosquito-abatement, and development for agricultural, industrial, and residential purposes.   Most of the existing mangrove habitat in the entire United States occurs along the west Florida coast.  Very little  mangrove habitat remains on the southeast coast.  Because mangroves serve as important juvenile habitat for these fish, their loss could affect population recovery even if reproductive levels of adult fish are high. 

     Red Tide

Red tide effects on goliath grouper are being evaluated at the National Marine Fisheries Service Laboratory.  Information available on the following site:  http//www.sefsc.noaa.gov/redtidegrouper.jsp.