Nearly a third of the wetlands along Long Island Sound have disappeared since the 1880s, representing a serious loss of this vital resource for coastal communities and for fish and wildlife, according to a study released Thursday.  

The study has been published by the U.S. Fish and Wildlife Service with assistance from the Connecticut Department of Energy and Environment and the New York State Department of Environmental Conservation.

Conducted under the Long Island Sound Study partnership, the work is the first long-term assessment of the changes in tidal wetlands in the Sound.

The study, “Status and Trends of Wetlands in the Long Island Sound Area: 130-Year Assessment,” estimates that there are 7,814 fewer acres of tidal wetlands around the Sound today compared to the 1880s, with the loss of 5,262 acres in Connecticut and 2,552 in New York.

The majority of wetland loss occurred before federal and state laws were adopted in the 1970s to protect wetlands from dredging and filling related to land and port development, the Long Island Sound Office of the Environmental Protection Agency said in a news release.

The study did find a modest gain since the 1970s in Connecticut wetlands, which increased by 1,123 acres, or 8 percent.

New York saw a decline since the 1970s of 674 acres, a 19 percent loss, resulting from several factors including sea level rise, the EPA said.

The analysis called for further study to determine causes of this decline.

More than 80 percent of wetlands along the Long Island Sound coast are in Connecticut.

“Tidal wetlands provide critical habitat for an impressive variety of vegetation and marine life as well as serving as an important buffer to protect properties and infrastructure from coastal storms,” said Robert Klee, commissioner of DEEP. “The work done to enhance and restore tidal wetlands in Connecticut has made a real contribution to improving the natural resources and environment of our Long Island Sound coastline. Analyses such as these will help us continue to work closely with our partners in pursuit of restoration projects and other management efforts that address conventional issues as well as the new challenges to our shore raised by climate change.”

EPA Region 2 Administrator Judith Enck said the report is a call to action by government and businesses to reverse the trend of wetlands loss.

“Wetlands provide enormous economic, environmental and flood protection benefits, but they are threatened by overdevelopment and the impacts of climate change,” she said. “By working together, government and Long Island Sound communities can strengthen shorelines and the health of wetlands, protecting water quality, fish and wildlife habitats, and coastal communities."

The report was based upon the best available sources of tidal wetland data from the 1880s, 1970s and 2000s.

Researchers did not definitively conclude why Connecticut wetland habitats have increased since the 1970s, but cited as possible factors efforts to restore habitats, higher elevation marshes that are more resilient to salt water intrusion from sea level rise or other causes, and proximity to river systems such as the Connecticut River that carry sediment downstream to help stabilize marshes.

Despite the gain, the study cautioned that a survey of large salt marshes in Connecticut, conducted as part of the research, found a high amount of permanent open water on the marsh surface, an indication that Connecticut wetlands may also be stressed.

The report recommended setting goals to protect a publicly desired level of wetland condition and function around the Sound, addressing site-specific threats, and securing the public’s support for large-scale restoration could help change the course of wetland loss in Long Island Sound.

The study can be found at: http://www.fws.gov/northeast/science/sciencenews/wetlandslongislandsound.html.