By Cheyenne Ellis
Great Meadows Marsh, a 225-acre saltmarsh in Stratford, Connecticut, has long been known as one of the largest and most diverse marsh habitats in Connecticut. Despite this, the site is currently facing unprecedented threats from rising sea levels and invasive plant takeover. Three of the marsh’s most at-risk species are struggling with increased habitat loss. Increasingly rare high marsh ecosystems are disappearing. Even the local community is having trouble visiting—pooling waters throughout the marsh bring in hordes of mosquitoes, making it virtually inaccessible in the summer months. All of these dangers make for a terrifying realization: if this is happening at one of the most prolific marshes in Connecticut, what does this mean for the future of our smaller marshlands?
Luckily for Great Meadows Marsh, a team of state, federal, and non-profit environmental organizations from across Connecticut have come together with the same goal in mind: to restore Great Meadows to its former glory. The project, which is expected to begin this fall, will become one of the largest restoration projects Connecticut has ever seen.
This project has been a long time coming. The problems at Great Meadows Marsh (a unit of the Stewart B. McKinney National Wildlife Refuge) began in the 1950s when soil dredged from the Bridgeport Harbor was placed with the marsh, creating uplands infested with invasive phragmites and other vegetation where there once was salt marsh. This, in addition to sea level rise, has resulted in habitat loss for several species that are limited to brackish water conditions. Much of the marshlands are disappearing through a process called coastal squeeze, which Jim Turek, a restoration ecologist for NOAA, defines as when the marsh is invaded by seawater, but has nowhere to move due to urbanization.
“The uplands next to the marsh have been developed so there’s not an opportunity for the marsh to migrate along with the increase in sea level rise,” said Turek. “The marsh is being squeezed on the sea level side by the fact that it’s more and more flooded and it can’t tolerate that flooding. On the landward side, there’s nowhere for the marsh to go because it’s all been developed.” With its proximity to several large urban areas, Great Meadows is at an increased risk of seeing marshland habitat disappear.
What makes Great Meadows unique is its size and diversity in comparison to other marshlands. The amount of biodiversity makes the site more resilient to threats. Smaller saltmarshes and wetlands throughout the Long Island Sound are not so lucky—the Ramsar Convention’s 2015 Global Wetland Outlook found that wetland habitats are disappearing three times faster than forests. Many saltmarshes cannot keep up with the pace of sea level rise. For that reason, it is of the utmost importance to protect and revitalize our remaining marshlands in any way we can.
Connecticut’s Environmental Organizations Work Towards a Common Goal
Corrie Folsom-O’Keefe, Director of Bird Conservation for Audubon Connecticut, remarks that one of her favorite parts of this project is watching a variety of organizations come together to make this project successful. Key partners in this project include the Great Meadow Trustees, consisting of the US Fish and Wildlife Service, the NOAA Restoration Center, and CT DEEP. Audubon Connecticut recently joined in on the project when the main partners were in search of a non-governmental organization to partner with in order to apply for additional funding.
“Audubon had actually just finished a three-year strategic plan, and we felt that saltmarsh nesting birds were one of the groups of birds that were most at risk as a result of sea level rise,” said Folsom-O’Keefe. “It was perfect timing! Audubon has done a strategic plan and decided this was what was going to be a big focus of ours and the Great Meadows Trustees were looking for an NGO to become a member of the partnership so we jumped onboard.”
The Long Island Sound Futures Fund has awarded the project $499,974, with $500,249 in matching funds. Additionally, the Long Island Sound Study Enhancement Grant Program awarded the project $2,000,000 to help fund the construction, project oversight, and other costs related to the project. There is also $838,492 in Natural Resource Damages settlement case funds coming to the project.
Many other organizations throughout Connecticut are planning to get involved as well, making this truly a collaborative effort. The Nature Conservancy, Atlantic Coast Fish Habitat Partnership, The Schuman Foundation, The Jeniam Foundation, and the Department of the Interior (via the Atlantic Coast Fish Habitat Partnership, USFWS Refuge and Coasts Programs) have all committed funding to the project. Additionally, Save the Sound, The Connecticut Audubon Society, The Nature Conservancy, Sacred Heart University, the Menunkatuck Audubon Society, and the Friends of the Stewart B. McKinney National Wildlife Refuge have all pledged to help organize the volunteer effort in the spring.
Monitoring Great Meadows with LiDAR Technology and Lab Testing
Thanks to advancements in monitoring technologies, planning for the restoration of Great Meadows Marsh was an accurate and efficient process. One of the new techniques that the team utilized was an aerial drone with LiDAR (Light Detection and Ranging) technology, which was able to accurately capture the ground elevations through the vegetation covering, producing results within a two-inch accuracy. To do this, the drone shoots and records a laser beam many times across the ground. The beams then bounce back and can measure the distance it traveled. While spot checks were also done by experts on the ground to verify these findings, drone technology is more cost-effective and quicker than previous methods, which involved taking a series of aerial photographs from a plane and interpreting multiple images side-by-side by an expert. The Great Meadows restoration marks one of the first times LiDAR technology was used for measuring topography in Connecticut.
In addition to determining marsh elevations, researchers also investigated soil conditions. Samples were taken from test pits and brought to a lab, where they underwent a 16-week analysis. Each week, while the soil was dampened and gradually exposed to oxygen, acid levels were recorded. The pH level on any sample changing quickly, or dropping below a certain level, was an indication that sulfates were present, which can result in the production of sulfides. If sulfides are then exposed to oxygen, they can create sulfuric acid, which is toxic to plants. Most soil showed low levels of sulfides, but any soil that appears to be at risk will be strategically placed or amended with lime to help restore the marsh.
These two tests were far from the only monitoring done at Great Meadows. The year-long research effort included several other testing methods including a survey of endangered plant species, an evaluation of topographic data from a 15-year time span, an analysis of tidal gauge data from Bridgeport, and an inventory of the plant and animal communities that reside in the marsh. With all of this data, participating organizations were able to come together to agree on a restoration action plan for Great Meadows.
From Soil to Seed: The Great Meadows Restoration Plan
The restoration process has been broken into two main steps: soil replacement in the fall and a mass planting effort in the spring.
Starting in the fall of 2021, contractors will begin moving soils to better suit the needs of the marsh. Soil shown to contain sulfuric acid compounds will be treated to prevent any risk to native plants. In areas with invasive phragmites, the top six inches of soil will be removed and taken off-site to prevent any roots from remaining in the soil.
Additionally, due to fill being placed unevenly on-site decades before, some parts of the marsh are currently at an elevation that is too high to contain any features of actual marsh habitat. In these locations, excess soil will be relocated to other parts of the marsh that will benefit from a higher elevation, such as the low-marsh areas battling the impacts of sea level rise. Much of this extra soil will also go to restoring the high-marsh at Great Meadows. These areas typically have sandy soil and are intolerant of frequent flooding. A number of threatened birds depend primarily on high-marsh to survive, which is what makes this soil restoration project is so important.
“What we’re seeing is less and less [high-marsh] habitat, not only on Great Meadows Marsh, but everywhere else in Connecticut and beyond,” said Turek. “It’s tragic that these species have a very specific habitat that’s disappearing. What we’re trying to do is restore some of that habitat for them and to do that, we have to bring up elevation.”
Soil restoration is not the only plan for Great Meadows this year. There will also be efforts to improve transitional tidal habitats throughout the site. Doing so will likely result in less pooled water, which is a known hang-out spot for the pesky mosquitoes that make the marsh very unpleasant in the summertime. This, in turn with the planned modified trails and observation platforms, will make the park more accessible for the local community.
With soil restoration set to be completed by spring, the marsh will be ready for a planting effort that will revitalize the habitats of several endangered species.
Great Meadows Needs Your Help Saving the Marsh Pink Wildflower
Perhaps the greatest hope of those involved in the project is improved habitat access for three of Connecticut’s most at-risk species—the diamondback terrapin, the saltmarsh sparrow, and the marsh pink wildflower.
The diamondback terrapin is a turtle species that nests exclusively in coastal tidal marshes. Because of the steep inclines at the marsh, accessing nesting locations has been a struggle for female turtles who have trouble making the climb. The area also has notoriously poor soil, not the sandy kind which is preferred by terrapins, which makes their nests less secure from predators and flooding. Part of the restoration efforts include lowering parts of the marsh with steep inclines, which will help these turtles get to their nesting locations and find better soil to nest in.
The saltmarsh sparrow is a bird whose primary nesting location is inches above the high tide line. Typically, the tide is high enough at a full moon and new moon to completely wash these nests away, giving the birds only around 23 days to completely incubate and raise their chicks. Unfortunately, with sea level rise, this short window of time is decreasing even more as the tide becomes high enough to wash the nest away even before the moon reaches these stages.
O’Keefe and the rest of the Audubon Connecticut team will be testing out a new hypothesis at Great Meadows—will saltmarsh sparrows be willing to nest on raised hummock beds? If so, these hummocks will give the nests a few more inches above the high tide line, buying them some extra nesting time. O’Keefe cannot stress enough the importance of saltmarsh sparrows as indicators for the health of our marshes.
“The saltmarsh sparrow is kind of like the canary in the coal mine—oh my god, if we lose the saltmarsh sparrow, we’re in trouble,” she said.
The final targeted species of this project is the marsh pink wildflower. Currently, Great Meadows Marsh is the last known site that supports the flower in Southern New England. While marsh pink does not grow in the actual saltmarshes, its preferred habitat is just upslope, where the ground is moist, but not salty. With this habitat disappearing more and more each year, the flower has become increasingly rare.
Marsh pink is an annual that requires seed dispersal each year. Luckily for them, they will have some assistance this spring with the help of a massive volunteer effort currently being organized by many of Connecticut’s environmental organizations. While planting marsh pink is an easy task, the restoration team is hoping to plant a few hundred thousand of these seedlings, meaning they need all of the help they can get. Planting is expected to begin in April or May of 2022.
While these three are the species receiving the most direct restoration efforts, O’Keefe is optimistic that everything being done at Great Meadows Marsh over the next year will be highly beneficial to every living thing that resides in or visits the marsh.
“There are three focal species, but there’s benefits to fish populations, as well as other bird species,” said O’Keefe. “The surrounding community also benefits in terms of being able to visit the marsh.” From flood protection to ecosystem health, the benefits of having a more resilient marsh are simply too numerous to count.
If you or someone you know would like to get involved with the marsh pink planting volunteer efforts in April and May of 2022, please don’t hesitate to get in contact with Corrie Folsom O’Keefe ([email protected]).
Sunlight hitting Great Meadows Marsh. Credit: Frank Mantlik.
Great Meadows at sunset. Credit: Frank Mantlik.
Aerial photo of Great Meadow Marsh and surrounding areas. Credit: Jim Turek.
Two culverts at Great Meadows Marsh that will be replaced during the restoration process. Phragmites will also be removed from this area. Credit: Corrie Folsom-O’Keefe.
A meadow in Great Meadows Marsh with invasive phragmites taking over native plants. Credit: Corrie Folsom-O’Keefe.
Willet at Great Meadows Marsh, who nest on site. Credit: Corrie Folsom-O’Keefe.
Clapper Rail at Great Meadows Marsh, Who Nests on Site. Credit: Corrie Folsom-O’Keefe.
The marsh pink wildflower in its habitat at Great Meadows. Credit: USFWS.
Marsh pink at Great Meadows. Credit: USFWS.
Egrets, herons, and ducks at Great Meadows, alongside some invasive phragmites. Credit: Frank Mantlik.
A saltmarsh sparrow in nesting grass habitat saltmarsh grass habitat (Spartina alterniflora) at Great Meadows Marsh. Credit: Frank Mantlik.
Osprey nesting at Great Meadows. Credit: Frank Mantlik.