Current and ongoing research
Informing project design and long-term monitoring and adaptive management of large-scale ecosystem restoration to maximize natural resource benefits through the protection and enhancement of seagrass habitat at the Chandeleur Islands, LA
In their efforts to restore the Chandeleur Islands off coastal Louisiana, natural resource agencies must use the best available science and develop a long-term monitoring and adaptive management plan that maximizes benefits for key natural resources, in particular seagrass. The project team, which is a multidisciplinary collaboration across universities, state and federal agencies, a non-profit research institute, and local government, and collaboration through a co-production of science framework, is collecting spatial and temporal data at population and landscape levels to determine disturbance impacts and build on existing numerical models to better assess resilience capacity for seagrass habitats adjacent to the Chandeleur Islands. You can read more about this project, funded by the NOAA RESTORE Science Program, here.
northcentral gulf seagrass monitoring program
We lead the Northcentral Gulf Seagrass Monitoring Program to investigate changes in seagrass distribution and condition over space and time at more than 300 stations across Louisiana, Mississippi, and across the Florida Panhandle. The program, which was established in 2018, uses a tiered seagrass monitoring framework to sample stations annually for a suite of seagrass and water quality parameters. Funding for the program is provided from a variety of partners including National Park Service, U.S. Geological Survey, U.S. Army Corps of Engineers, Pensacola and Perdido Bays Estuary Program, NOAA RESTORE Science Program, and Mississippi Department of Marine Resources. Learn more here.
carbon accumulation in mississippi seagrass meadows
This project, which is the focus of student Devan Hildebrand’s Master’s thesis, is a partnership with U.S. Geological Survey and Natural Resources Conservation Service, and quantifies carbon accumulation and sequestration in seagrass meadows along Cat Island, MS. For this study, 2 meter-deep soil cores were collected within and outside of seagrass meadows and are being analyzed for a suite of biogeochemical parameters.
Investigating seagrass reproductive effort across the northern gulf
Seagrass reproductive effort varies widely in space and time. Ph.D. student Caitlin Young is investigating turtlegrass reproductive output and reproductive history at the Chandeleur Islands, LA, and in Florida Bay, FL to examine resilience capacity.
past projects
reconstructing the reproductive history of turtlegrass along the florida panhandle
Like all seagrass species, turtlegrass (Thalassia testudinum) is capable of both asexual propagation through horizontal rhizome elongation and sexual reproduction. Each flower produced by the plant leaves a distinguishable scar on the plant’s vertical rhizome, allowing for reconstruction of the plant's reproductive history. Further, each leaf produced by the plant results in a scar, and the quantity and relative placement of the distinct leaf and flower scars provides a more complete understanding of plant age and reproductive history. This effort, which is aimed at reconstructing the reproductive history of turtlegrass in distinct meadows across the Florida Panhandle, follows previous work on spatial and temporal variability in seagrass reproductive output and environmental controls to flower production.
Gulf-wide assessment of habitat use and habitat-specific production estimates of nekton in turtlegrass
Turtlegrass is a critical foundation species that provides energy for food webs and shelter and foraging grounds for many species. This project is a management-driven, three year Gulf of Mexico-wide assessment of turtlegrass habitat use by finfish and shellfish and an evaluation of the specific ways it supports blue crabs, a commercially important species which has seen recent declines in harvest in many Gulf states. We will examine the abundance, diversity, age, and mix of juvenile and adult animals that use turtlegrass as habitat in Florida, Louisiana, and Texas. We are excited to collaborate with Lee Smee (Texas A&M University- Corpus Christi), Charlie Martin (University of Florida), Penny Hall (Florida Fish and Wildlife Conservation Commission) and Brad Furman (Florida Fish and Wildlife Conservation Commission) on this effort. This is one of 15 projects funded by the NOAA RESTORE Act Science Program in FY2017. You can view the announcement here and read more about this project on our Project Hub.
gulf-wide assessment of shoalgrass dormant seed densities
Seagrass propagation can occur asexually through later extension of belowground rhizomes, or sexually, through the production of flowers, fruits and seeds. For individual species, understanding the relative importance of each reproductive mode is necessary for successful management and accurate predictions under future scenarios. Shoalgrass (Halodule wrightii), a sub-tropical seagrass species, is one of the dominant seagrasses in the Gulf of Mexico and provides essential habitat for fish and invertebrates. Shoalgrass produces small (2 mm) seeds that can remain dormant in the sediment for several years before germinating. This effort spanned Texas to Florida. You can read about project results here.
linking blue crab abundance, growth and mortality to marsh fragmentation and submerged aquatic vegetation cover
Despite coastal land loss and landscape fragmentation, the Louisiana coast supports the largest commercial blue crab (Callinectes sapidus) fishery in the Gulf of Mexico, in terms of both landings and wholesale value. However, as marsh continues to fragment and the landscape changes, predicting and managing the blue crab fishery is particularly challenging. Understanding the relationship between marsh fragmentation and blue crab fishery production has been identified as a critical research need throughout the Gulf of Mexico, and in Louisiana, as climate change- and subsidence-induced marsh fragmentation is occurring at an unprecedented rate in this region. This field-based study, which is a collaborative effort with Tim Carruthers (The Water Institute of the Gulf) and Zack Darnell (The University of Southern Mississippi), is aimed at understanding the effects of marsh fragmentation and submerged aquatic vegetation cover on abundance, growth and mortality of juvenile and adult blue crabs.
submerged aquatic vegetation as a nutrient bionidicator
The Louisiana coast supports a diverse assemblage of submerged aquatic vegetation that span both salinity (freshwater to saltwater) and nutrient (low to high) gradients. Freshwater and brackish water-tolerant submerged plants grow across most of the Louisiana coast, whereas saline-adapted species (seagrasses) are restricted to growing offshore along the Chandeleur Islands. Essential baseline data on plant dynamics, including species-specific nutrient content, are lacking for many of these species, despite the necessity of this information for predicting chance, and the potential for using plant nutrient content as a bioindicator of surrounding nutrient conditions. In a collaboration with Tim Carruthers (The Water Institute of the Gulf), Megan La Peyre (USGS and Louisiana State University), Kristin DeMarco (Louisiana State University) and Eva Hillmann (Louisiana State Univeristy), we are examining patterns in nutrient levels and stable isotope ratios from freshwater and brackish water submerged aquatic vegetation collected in an extensive northern Gulf of Mexico-wide survey in 2014.
In a separate collaboration with Tim Carruthers, Patrick Biber (The University of Southern Mississippi), Ioannis Georgiou (Univerity of New Orleans), Tommy Michot (University of Louisiana at Lafayette) and Ron Boustany (USDA), we have investigated decadal-scale patterns in nutrient content of seagrasses at the Chandeleur Islands and the linkage between seagrass nutrient content and outflow from the Mississippi River that you can read about here.