The authors evaluated Goliath Grouper’s use of mangroves as essential nursery habitat by estimating absolute abundance, density, survival, age structure, home range, mangrove habitat association, habitat quality, and recruitment to the adult population. REEF Volunteer Fish Survey Project data from 1993 to 2004 collected in Florida were used to determine sighting frequency of Goliath Grouper. These data were then compared with the abundance of two major estuarine habitat types in coastal Florida, mangrove habitat and seagrass habitat. The authors found that the abundance of adult Goliath Grouper at offshore sites was largely explained by abundance of mangrove, but not seagrass habitat. These findings point to the importance of mangroves as nursery habitat.