LIS Habitat Restoration Initiative: In Depth

The Habitat Restoration Initiative follows through on recommendations made in the Comprehensive Conservation and Management Plan that the Long Island Sound Study develop a plan to restore the Sound’s degraded coastal habitats. The Habitat Restoration Work Group was formed to coordinate these efforts and to strengthen partnerships among various agencies and organizations conducting restoration projects.

The Habitat Restoration Work Group identified 12 priority habitats as being particularly important to sustaining the living resources of the Long Island Sound ecosystem (see the 12 Types of Priority Habitats).

To accomplish the goals of the Habitat Restoration Initiative, the work group compiled a list of potential habitat restoration sites, including site nominations provided by the public, and then ranked the sites based on criteria in three major categories: ecological value; technical viability; and public benefit. Additional factors such as the presence of a local sponsor, an existing design plan, or available funding were also considered. The sites that were determined to be high priorities are targeted by the work group in the annual work planning process. However, factors like available funding and advanced project planning are important in initiating restoration projects, regardless of their rank. The Habitat Restoration Map includes the full list of the potential restoration sites identified and some examples of completed projects.

Accomplishments

The Habitat Restoration Initiative’s recent accomplishments include the following:

• The critical estuarine habitat known as submerged aquatic vegetation – dominated by eelgrass (Zostera marina), a habitat whose distribution and health are strongly influenced by water quality – was mapped by the US Fish & Wildlife Service Coastal Program (USFWS) in 2002. The Long Island Sound Study provided the USFWS with additional funds to remap the Sound’s eelgrass beds in 2006 in order to document trends in eelgrass cover.
• Restoration projects continue to be accomplished through partnerships and by leveraging resources from a variety of federal, state, municipal, nonprofit and private sources. Some examples include:In 2004, the Long Island Sound Study developed a grant program with the National Fish & Wildlife Foundation that identified habitat restoration projects as priorities for funding. The first awards from the Long Island Sound Futures Fund, which were announced in May 2005, included four habitat restoration projects and four projects that will restore or improve fish passage.CTDEEP and Coastal America worked with Northeast Utilities and Duracell to create the CT Corporate Wetland Restoration Partnership in 2000, which provides private funds or services for the restoration of wetlands and riverine migratory corridors in CT.

NYS DEC has been working to reestablish the NY Corporate Wetland Restoration Partnership, which is expected to award grants for restoration projects in NY in 2006.

Habitat Restoration Technical Manual

In 2003, the Long Island Sound Study published a manual entitled Technical Support for Coastal Habitat Restoration, which includes a series of reports produced through the Habitat Restoration Work Group. The manual is designed to provide basic technical information about the Sound’s coastal habitats and restoration practices for persons interested in planning a restoration project.

An Emerging Issue: Tidal Marsh Loss

Throughout the northeast, tidal marshes are turning into mudflats, resulting in the loss of vegetated habitats important for wading birds, juvenile fish, and invertebrates. Tidal marsh loss—the loss of elevation relative to sea level and conversion of vegetated marsh to mudflat—has been observed in Long Island Sound since the 1980s. However, recent studies indicate that the magnitude and distribution of these losses, which are primarily occurring in the western Sound, are far greater than previously realized. At the Quinnipiac River, for example, nearly half of the brackish marshes in a 130-acre site have disappeared since 1974. The Long Island Sound Study is working to gain understanding of and draw attention to this phenomenon.

Additional Details

Significant areas of tidal wetland loss within Long Island Sound and coastal wetlands elsewhere in New England have prompted scientists to investigate changes in these marshes with respect to relative sea-level rise. In 2001, Dr. Nels Barrett of the Connecticut Natural Resources Conservation Service proposed establishing a long-term program to monitor the elevation dynamics of tidal marshes using surface elevation tables (SETs), a technique promoted by Dr. Don Cahoon of United States Geological Survey Pawtuxent Wildlife Research Center.

Barn Island Wildlife Management Area, in Stonington, CT

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 Energy and Environmental Protection (CTDEEP), 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.

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. CTDEEP’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 CTDEEP and NYS DEC to determine the rates of tidal marsh loss in the Sound. Through an agreement with CTDEEP, 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, formerly of the University of Connecticut, and Dr. Martha Gilmore of Wesleyan University  collaborated 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 focused 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 tested 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.

Anisfeld also assessed 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 tested whether experimentally adding nutrients will lead to the initial symptoms of marsh drowning. The research, completed in 2008 (see report), is helping 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.