Marsh Food Webs

The Team: Michael J. Polito (Lead Investigator, Louisiana State University, mpolito@lsu.edu), Annette S. Engel (University of Tennessee-Knoxville), Linda M. Hooper-Bui (Louisiana State University), Olaf P. Jenson (Rutgers University), Paola Lopez-Duarte (Rutgers University), Charles W. Martin (University of Florida), Jill A. Olin (Michigan Technological University), Nancy N. Rabalais (Louisiana Universities Marine Consortium and Louisiana State University), Brian J. Roberts (Louisiana Universities Marine Consortium), and Erick Swenson (Louisiana State University)

Technical Monitors: Melissa Carle (melissa.carle@noaa.gov) and Ian Zink (ian.zink@noaa.gov)

Federal Program Officer/Point of Contact: Frank Parker (frank.parker@noaa.gov)

This project began in June 2017 and will end November 30, 2023.

Award Amount: $2,057,684

Why it matters: Coastal land loss in Louisiana has claimed more than 4,800 km2 since the 1930s. Without preventative action, an additional 4,500 km2 of land will disappear in the next 50 years. Restoration efforts have included modifying hydrologic patterns and construction of tidal marshes and river diversions to reconnect the Mississippi River to adjacent estuaries. While these restoration efforts have shown promise for reducing land loss, little is known about their impacts on the composition of the plants and animals in a coastal marsh and their food web structure.

What the team is doing: This research seeks to expand knowledge of the effects of river diversions on natural versus created marshes in Louisiana. Researchers will determine species composition, abundances, and food web structure in natural marshes along varying levels of salinity that result from a river diversion. They will also examine species composition, abundances, and food web structure in created marshes that differ in age influenced by this same river diversion. Finally, the data collected from the marshes will be incorporated into an ecosystem model to predict the impact of salinity changes and habitat restoration efforts on marsh food web structure, function, and resilience.

Expected Outcome: This project will increase understanding of how river diversions impact the marsh food webs and provide the means for predicting how certain types of restoration will impact the species living in a marsh. This project will consider the majority of components in marsh food webs and make it possible for managers to take an end-to-end ecosystem perspective when making management decisions.