SETs are tools for measuring changes in marsh surface elevation and sedimentation. With funding from the Long Island Sound Fund, a grant program administered by the Connecticut Department of Environmental Protection (CT DEP), Dr. Barrett partnered with Dr. R. Scott Warren of Connecticut College and Dr. Cahoon to establish SET arrays at Barn Island in Stonington, Connecticut. The nine SET benchmarks were constructed as a first step toward an envisioned network of SETs throughout the Sound.
mBarn Island Wildlife Management Area,   mStonington, CT

In June 2003, the Long Island Sound Study sponsored a workshop, developed by the New York State Department of Environmental Conservation (NYS DEC), for researchers to discuss and share information regarding the possible causes of tidal marsh loss in the Sound. The goal of the workshop was to develop research, monitoring and management recommendations. The participants highlighted the need to gather baseline information on the health and spatial distribution of the Sound’s marshes and identified priority research topics (see workshop summary). The Long Island Sound Study is helping to address these recommendations by supporting projects to examine coastal wetland trends in the Sound and to investigate potential causes of the observed subsidence.

To help gather baseline information on marsh health, workshop participants supported Dr. Barrett’s recommendation that a network of SETs be established around the Sound. CT DEP’s Office of Long Island Sound Programs, with funding from the Coastal Zone Management Program, has purchased 20 SET arrays that will be deployed in Connecticut marshes in 2005. The Long Island Sound Study has provided support for NYS DEC, in partnership with the Marine Sciences Research Center at Stony Brook University, to install and monitor SETs in New York marshes.

The Long Island Sound Study also is funding efforts by CT DEP and NYS DEC to determine the rates of tidal marsh loss in the Sound. Through an agreement with CT DEP, the US Fish & Wildlife Service is interpreting wetland boundaries from archival aerial photographs, taken between 1974 and 2000, of strategic coves and tidal rivers in the Connecticut portion of the western Sound. In New York, NYS DEC will acquire aerial infrared photography of tidal marshes and will examine wetland trends using these images and aerial photographs dating back to 1930.

Dr. Daniel Civco of the University of Connecticut and Dr. Martha Gilmore of Wesleyan University are collaborating on a project to identify and delineate coastal marshes around Long Island Sound and distinguish various types of marsh vegetation. With support from a Long Island Sound Study research grant, these researchers are identifying and inventorying the current extent and condition of the Sound’s coastal marshes. They also are developing a cost-effective way to track changes in the condition of wetlands over time using remote sensing satellite imagery coupled with in situ radiometry and other field data collection. These datasets and protocols can help provide coastal resource managers, municipal officials and researchers with baseline information for current land management and for long-term monitoring of habitat changes.

One hypothesis formulated at the tidal wetlands loss workshop was that excessive loading of nutrients such as nitrogen and phosphorous plays a role in causing marsh loss. In 2004, the Long Island Sound Study awarded a research grant to Dr. Shimon Anisfeld of Yale University to investigate the possible role of nutrients in contributing to marsh drowning. Anisfeld’s research focuses on whether high levels of nitrogen, while increasing aboveground plant production, might actually decrease the growth of below-ground material, such as roots. Anisfeld also is testing a theory that, as nutrients increase in the marsh peat, bacteria increase and consume more organic matter.

Tidal Marsh research project at Sherwood Island St. Park. Photo: Suzy Allman

Anisfeld is assessing site conditions and factors, including nutrient levels, at three Connecticut marshes: a degraded marsh at Sherwood Island State Park in Westport; a stable marsh at Hoadley Creek in Guilford; and a restored marsh at Jarvis Creek in Branford. At Hoadley Creek, Anisfeld is testing whether experimentally adding nutrients will lead to the initial symptoms of marsh drowning. This research, which will be completed in 2006, will help ascertain if nutrient loading is a factor in tidal marsh loss. These efforts to monitor trends in the Sound’s coastal habitats and to investigate potential causes of tidal marsh loss are critical to understanding the changes occurring in the Sound’s marshes.

The partnerships fostered by the Long Island Sound Study provide a unique opportunity for the states of Connecticut and New York, local researchers, and federal agencies to work together on developing strategies to minimize tidal marsh loss and protect coastal habitats. Despite these losses, restoring degraded tidal wetlands continues to be a high priority for the Habitat Restoration Work Group, and restoration plans are being modified so as to minimize submergence losses at restoration sites. Back to top