Sponsor: NOAA Restore
Award Dates: 2017 –2022
Investigators: Kelly M. Darnell (The University of Southern Mississippi), Zachary Darnell (The University of Southern Mississippi), Delbert L. Smee (Texas A&M University-Corpus Christi), Charles W. Martin (University of Florida), Bradley Furman (Florida Fish and Wildlife Conservation Commission), and Margaret O. Hall (Florida Fish and Wildlife Conservation Commission)
Marine habitats such as seagrass beds serve as habitat for many commercially and recreationally important finfish and shellfish during some stage of their life. In the northern Gulf of Mexico, a widespread and ubiquitous species of seagrass is turtlegrass Thalassia testudinum. Turtlegrass is a critical nursery habitat, serving as a food source that provides a basal resource for food webs and shelter and foraging grounds for many faunal species. In order for fisheries managers to understand how changing seagrass abundance impacts fisheries, we sought to determine how turtlegrass supports finfish and shellfish species at the regional scale in the Gulf of Mexico.
We assessed turtlegrass habitat in several areas throughout the Gulf of Mexico, including Texas (Coastal Bend and Laguna Madre), Louisiana (Chandeleur Islands), and Florida (St. George Sound, Cedar Key, and Charlotte Harbor). We used trawls and benthic sleds to assess habitat use and community composition, as well as a detailed evaluation of the specific ways turtlegrass supports blue crabs. Specifically, we measured the relationships between seagrass characteristics (e.g., plant density, surface area, height) and faunal communities, as well as blue crab growth and mortality in these three states. Finally, are developing separate statistical models for Florida, Louisiana, and Texas that will estimate blue crab production in turtlegrass based on crab abundance, growth, and mortality data.