Research Projects

Ecological Effects of Sea Level Rise

Grand Bay, and other National Estuarine Research Reserves, are well suited to monitor the effects of sea level rise because of their coastal location and growing infrastructure.  Grand Bay NERR staff and collaborators are installing equipment to monitor changes in marsh elevations and plant association changes over time while conducting experiments to better understand potential impacts and response of coastal marshes to increasing sea levels.

More information about Grand Bay’s Sentinel Site Program, a large part of our effort to monitor sea level rise, can be found here.

Highlights –

  • Installation of water level monitoring equipment and a temporary tide station;
  • Field experiments to model the potential response of marsh grasses, oysters, and plant communities to rising water levels;
  • Field experiments to understand the effects of hurricane storm surge;
  • Partner in the NOAA Sentinel Site Cooperative for the Northern Gulf of Mexico; and
  • Partner in the NERRS Sentinel Site Program.

Ecology of Tidal Marsh Vertebrates

Grand Bay NERR staff and collaborators lead a variety of long-term monitoring and research projects focused on tidal marsh vertebrates including estuarine fishes, diamondback terrapins, and breeding marsh birds.  In addition, staff have conducted short-term monitoring efforts focused on winter shorebirds and winter marsh birds.  Many of these species have not been well studied, especially along the Gulf coast.  The goals of these efforts are to gather data on the abundance and distribution of these species, better understand their ecology, and provide context for broader ecological processes, as well as human and natural stresses on tidal marsh ecosystems.


  • Since 2005, we have collected approximately 500 fish community samples from 14 sites across the Reserve during our quarterly monitoring;
  • We have documented important nesting sites for diamondback terrapins, and discovered how their nesting behavior differs from terrapins in other parts of their range;
  • Reserve staff and collaborators have established breeding marsh bird survey sites at over 200 locations in coastal Mississippi; and
  • Results from studies of Clapper Rails and Seaside Sparrows, two species of secretive marsh bird, have led to multiple publications in addition to informing management plans.

Ecology of Special Habitats

The Grand Bay Reserve has some of the most extensive and best examples of salt pannes, shell middens, and submerged aquatic vegetation in Mississippi, and along the northern coast of the Gulf of Mexico.  These habitats are imperiled in Mississippi because of their overall rarity.  Several studies have contributed to a better understanding of the occurrence and distribution of these habitats within the Reserve.

Highlights –

  • During a study of salt panne ecology, we documented two shrimp species, eight fish species, two gastropod species, three crab species, 20 orders of terrestrial arthropods (mostly insects), 10 mammal species, 20 plant species, and 58 bird species;
  • Artifacts from 500 B.C. to 1700 A.D. have been identified during archaeological studies of the Reserve’s shell middens; and
  • Distribution and abundance of shoal grass (Halodule wrightii) and widgeon grass (Ruppia maritima) have been tracked seasonally since 2003.

Monitoring Ecosystem Effects of Atmospheric Mercury

Two mercury monitoring stations located at Grand Bay measure the amount of mercury from the atmosphere.  An atmospheric mercury monitoring station measures dry mercury deposition, carbon monoxide, sulfur dioxide, nitrogen oxides, ozone, and black carbon.  A wet deposition station monitors total and methyl mercury concentrations, major ions, and trace metals in rainfall.  Together, these stations help to identify local and distant sources of mercury – important in the Gulf of Mexico, where some of the highest mercury deposition rates occur.  Several research studies are examining mercury levels in select organisms from across the Reserve, including birds, fish, and invertebrates.

Highlights –

  • Grand Bay is one of the only sites nationwide that monitors atmospheric mercury.  There are fewer than 20 sites in the Atmospheric Mercury Network (AMNet) and wet deposition is monitored at fewer than 100 sites nationwide;
  • An atmospheric monitoring station has been in operation since 2006, in partnership with the NOAA Air Resources Lab;
  • A wet-deposition station has been in operation since 2010, in partnership with the Mississippi Department of Environmental Quality;
  • Grand Bay has been the site of several intensive atmospheric mercury research experiments using aircraft and balloons;
  • Our site is part of the National Atmospheric Deposition Program’s National Trends Network, Mercury Deposition Network, and Atmospheric Mercury Network; and
  • We have developed an Atmospheric Mercury Monitoring and Research Cooperative, consisting of academic, state and federal government agencies, and non-government organizations, to guide future research and monitoring activities.

Coastal Plant Ecology and Mapping

The Reserve is a diverse coastal ecosystem, and encompasses some of the largest remaining estuarine marsh and wet pine savanna habitats in the state of Mississippi.  Studying the distribution, abundance, and health of plant communities in these habitats leads to a better understanding of environmental conditions such as elevation and salinity regime, and contributes to better habitat management.  NERR staff and collaborators involved in several large scale projects to document the Reserve’s flora.

Highlights –

  • A 12 km coastal transition transect was established to monitor plant communities in multiple habitats from Highway 90 south to the open water at the Grand Battures;
  • We are collecting detailed elevation, water level, and plant community data to evaluate the effects of climate change and sea level rise on coastal habitats; and
  • Collaborators and NERR staff are creating a Reserve-wide map of marsh plant species distribution and biomass.

Long-term Monitoring of Environmental Conditions

The System-wide Monitoring Program (SWMP) is a key component of every National Estuarine Research Reserve.  The program measures short and long-term change in estuarine conditions including water quality (e.g. water temperature and salinity), nutrients, and weather.  SWMP has three major components:  (1) abiotic indicators of water quality and weather; (2) biological monitoring; and (3) watershed, habitat, and land use mapping and analysis.

More information about Grand Bay’s System-wide Monitoring Program, a large part of our effort to monitor environmental conditions, can be found here.

Highlights –

  • Four water quality stations and one weather station were established in 2004. Real-time water quality and weather data are accessible online;
  • Over one million water quality, weather, and nutrient data points are collected and verified each year.  Over 12.3 million data points have been collected in total!
  • Our in-house laboratory analyzes over 1,000 nutrient samples annually;
  • SWMP data were used by the Mississippi Department of Environmental Quality to document the effects of a 2005 chemical spill in Bangs Lake;
  • We recorded only 42.5 inches of total annual rainfall during the 2011 drought, 20 inches below average; and
  • We measured the effects of hurricanes and tropical storms at Grand Bay, including Katrina (2005), Lee (2011), and Isaac (2012).
    • During Hurricane Katrina, we recorded water depth of 17 feet, and maximum winds of over 65 miles per hour just before the weather station was carried away by storm surge.
    • 13.5 inches of rain fell during Hurricane Isaac and over 22 inches of rain fell nearby in Pascagoula, MS.