Sedimentary, My Dear Watson: Saving Salt Marsh after Hurricane Sandy

Ask longtime coastal ecologist Marci Cole Ekberg what the biggest challenge is for the future of coastal marshes in Rhode Island, and she’ll tell you it’s the lack of sediment, a condition that became considerably more pronounced after the impact of 2012’s Hurricane Sandy.

“The Maidford Marsh region is accreting between 1 and 1.7 millimeters per year,” says the coastal ecologist for long-time Newport area environmental group and FWS partner Save the Bay. “So… not enough to keep up with sea-level rise.”

Nick Ernst and Marci Cole Eckberg discuss marsh elevation at Sachuest Point National Wildlife Refuge. Credit: Tom Sturm/USFWS

A lack of sediment can be a huge problem for coastal marshes that are facing rising seas and increasingly frequent and intense tropical storms fueled by climate change. Maidford Marsh is a relatively small area that shares an isthmus with Sachuest Point National Wildlife Refuge, but the challenge is a state-wide and even a global one. Ocean-borne storm and wave erosion combined with the lack of replenishment from estuaries whose rivers have been dammed or choked off by centuries of industrial development has left once-hardy tidal marsh ecosystems at a precipitous juncture where elevations cannot keep up with predicted sea level rise.

“You’ve heard it said in the world of real estate that it’s all about ‘location, location, location,’” says Susan Adamowicz, Ph. D., Land Management Research & Demonstration Biologist at Maine’s Rachel Carson National Wildlife Refuge.  “In these coastal ecosystems, it’s all about ‘elevation, elevation, elevation.’”

Adamowicz acknowledges that the pace at which a salt marsh system might be able to naturally adapt to changing conditions as been far outstripped by human development, increased storm activity and climate change-fueled sea-level rise. As someone who’s been witnessing the ongoing struggle for decades, she’s excited by the possibilities afforded by Hurricane Sandy resiliency funding to pursue solutions that can help return larger amounts of sediment to the coast and boost marsh elevation. Exactly what solutions?

“We can try to figure out what human alterations have been made to these sites, and undo them,” she suggests for starters. “Have we restricted tidal flows by a road crossing or railroad crossing so tidal waters don’t come in with the force that they used to, so they’re not able to bring in sediments from the coastal waters? Have we dammed up some of our rivers and not only prevented fish passage upstream for migratory fish, but also dammed off these sediments way up in the watershed and prevented them from coming down to the seashore?”

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Many U.S. Fish and Wildlife Service projects currently funded with Sandy resilience dollars, including marsh restorations in Delaware, New Jersey and a stretch from Rhode Island to southern Maine, focus on restoring sediment transport to help bolster healthy coastal marshes and enhance natural defenses that protect coastal communities and sustain people and wildlife. Damaged and undersized culverts are being replaced where needed, and obsolete dams are likewise being evaluated for removal, including several in Maryland,  Massachusetts, Rhode Island and Connecticut. Other, similar projects are being funded through the Hurricane Sandy Coastal Resiliency Grant program from the Department of the Interior and administered by the National Fish and Wildlife Foundation (NFWF).

At John H. Chafee National Wildlife Refuge, ten miles southwest of Sachuest Point on Pettaquamscutt Cove, the effects of lost marsh elevation are being felt by the salt marsh sparrow, a bird species of high conservation concern that builds nests down inside the deep swirls of grass that make up a healthy salt marsh. When marshes don’t accrete (build up their own sediment) enough to keep up with sea-level rise, the low nests are flooded and the sparrows’ eggs will wash away; already-hatched young will drown. Here, the U.S. Fish & Wildlife Service is in the early stages of perhaps the most drastic of remediation measures: dredging river-bottom sediment and depositing a skim of clean, tested dredge materials onto disappearing salt marsh (a technique known as thin-layer deposition).

Days-old salt marsh sparrows nest deep down in the thick, swirling marsh grasses. Credit: Margie Brenner/USFWS

“Depending on the sea-level rise, various models have the population going extinct in 50-60 years,” says wildlife biologist Nick Ernst, whose team at the Chafee refuge is using Hurricane Sandy resilience funding and years of accumulated research from the SHARP and I&M programs to try to improve conditions for the sparrows. “There’s not a lot of sediment to build up the salt marshes here; it’s a sediment-starved system. So we’re going to try to jump-start that process by putting thin-layer deposition—dredge material from the river—onto certain areas of the marsh to try to increase that elevation so the sparrows have a place to nest in the meantime, [while we] try to combat the sea-level rise we’re going to be witnessing over the next couple of decades.”

Test dredging and sediment deposit are scheduled to begin in late fall or early winter at the Chafee refuge, Ernst says, with full-scale implementation commencing in 2015-2016.

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For more information on how federal resilience funding is being used to clean, restore and enhance natural areas that were affected by Hurricane Sandy, please visit our Hurricane Sandy Recovery page. To read more detailed stories about funded projects in action, browse our blog posts here.

 

Birdseye View: Avian Science meets Hurricane Recovery

Tagging red knots on Cape Cod. The yellow tag is a geo-locator; the lime green alphanumeric flag means it was banded in the U.S. Credit: USFWS

While the  U.S. Fish and Wildlife Service continues to respond to damage from 2012’s Hurricane Sandy—clearing out wind-felled timber or hauling hundreds of tons of debris out of coastal salt marsh—the agency is also using science to assess the full scope of the storm’s ecological impact and establish a baseline for future conservation efforts. Some Service research that’s been integral to Hurricane Sandy recovery and resilience efforts is already visible in projects like the recently completed beach restorations along New Jersey’s Delaware Bay. This region has long been seen as indispensable to migrating shorebirds like the red knot, whose eastern population has plummeted 80 percent in the past decade.

While many of the most impacted bird species are shorebirds, studies by the Saltmarsh Habitat & Avian Research Program (SHARP), a collaborative effort between the Fish and Wildlife Service and several other academic, governmental, and privately funded partners, are focused more on marsh birds such as the seaside sparrow, the willet and the clapper rail. According to Randy Dettmers, a senior biologist with the Service, one project funded under the Hurricane Sandy umbrella (and preceded by supporting SHARP research) has targeted more than 1,700 observation points across tidal marshes from Maine to Virginia for post-Sandy monitoring of migratory bird populations.

Survey regions for USFWS/SHARP Tidal Marsh Bird monitoring.

Partners in the SHARP collaboration include the Universities of Maine, Delaware, New Hampshire, Connecticut and State University of New York (SUNY) College of Environmental Science and Forestry, as well as the Audubon Society, the National Park Service, the Maine Department of Inland Fisheries & Wildlife and many other state- and regionally based organizations. The program also employs dozens of graduate and undergraduate students who collect abundance, breeding and survival data by monitoring these sites and banding birds.

Student participants in the SHARP program, Left to Right: Chris Field, Univerity of Connecticut; Alison R. Kocek, SUNY College of Environmental Science and Forestry; Mo Correll and Meaghan Conway, University of Maine. Credit: Margie Brenner/USFWS

Another Sandy-funded project launched by Dettmers and Service colleagues Chris Dwyer and Scott Johnston examines the prevalence and distribution of submerged aquatic vegetation (SAV)—coastal plants that grow beneath the waterline and are primary food sources for wintering waterfowl, including the priority species Atlantic brant and American black duck. Studies of SAV in the wake of an intense storm like Sandy, Dettmers says, will provide an excellent picture of “how much of [the vegetation] is vulnerable to climate change impacts from sea-level rise and future major storm events and what the resulting impacts on wintering waterfowl populations are likely to be.”

American black ducklings nesting in coastal marsh. Credit: Peter McGowan/USFWS

Dettmers says the effects of predicted climate change will be increasingly challenging for coastal habitat and the species that depend on it. He expects that future storms and sea level rise will likely impact beach and tidal marsh habitats, affecting birds’ ability to find food and suitable nesting places, and that ultimately this may result in reduced bird populations.

“Species like the saltmarsh sparrow and seaside sparrow are endemic to the Atlantic coast marshes of North America,” he says.  “They don’t occur anywhere else in the world, and they’re highly vulnerable to sea-level rise and major storm impacts such as are expected from climate change. If tidal marshes in this part of the world are lost, we’ll lose those species as well.”

He adds that beach-dependent species like the red knot—already a candidate for threatened status under the Endangered Species Act because of other threats to its population—“will only be pushed further toward the endangered end of the conservation concern spectrum” if the loss of coastal habitat can’t be somehow stabilized.

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A clapper rail chick. Credit: Don Freiday/USFWS

To read more about the U.S. Fish and Wildlife Service’s Migratory Birds program, click here. To read more about the SHARP program and its constituent collaborating agencies and institutions, click here.

The U.S. Fish and Wildlife Service has been working to repair and restore public lands on the Atlantic coast since Hurricane Sandy impacted them in October of 2012. To learn more about the Service’s ongoing efforts to facilitate habitat recovery and build coastal resilience that helps protect communities, please visit www.fws.gov/hurricane/sandy.

 

Weathering the storm

I’m Allison Ludtke, and you’ll be hearing from me regularly over the next few months! I am a Student Conservation Association intern for Science Applications, focusing on telling stories about how we are working with partners to develop and apply science for landscape conservation across the Northeast. When I am not serving as an intern, I am a senior at the University of Massachusetts-Amherst, double majoring in wildlife ecology and journalism while completing an honors capstone project specializing in narrative nonfiction. I am passionate about wildlife conservation and truly believe communication can make a difference in how we deal with major issues like climate change.

I grew up spending my summers on the Cape. When I traveled there for Thanksgiving, my family discussed the impending erosion many of their neighbors are facing. Living about one hundred yards from the beach, they joked that sooner than later they’ll own beachfront property. Extreme, yes, but unlikely, no. As sea levels rise with a changing climate, the geology of these areas change and their natural resilience to intense storms is threatened.

Imagine if your beach front “backyard” suddenly crumbled into the ocean, or the streets of your town filled with water. Imagine losing all of your belongings, photo albums and objects holding dear memories. More importantly, imagine if you were injured – or worse, a loved one or family member was killed from these natural impacts.

This is reality.

The recent one-year anniversary of Hurricane Sandy (October 29) came and went, but the destructive storm’s impact still lingers.

Flooded homes in Tuckerton, N.J., on Oct. 30 after Hurricane Sandy made landfall on the New Jersey coast on Oct. 29 (US Coast Guard via AFP/Getty Images)
Credit: Boston.com

It has been argued that warming ocean temperatures contributed to the strength and impact of Sandy. As oceans warm, tropical storms and hurricanes that gather heat and energy through contact with warm ocean waters become larger and more powerful.  In addition, as ocean water warms and expands, global sea levels rise. Increased melting of ice caps and glaciers also contribute to rising sea levels. Storm surge from hurricanes on top of these higher sea levels will add up to increased erosion and inundation of coastal communities.  Predicting at risk areas is crucial, yet difficult, as beaches, barriers, and marshes all respond differently to warming, rising seas and storms.

Long Island Sound, part of the Connecticut River Watershed, is a perfect example of these effects. Home to an estimated 8 million people, Long Island Sound is a hotspot for heavy storm damage, due to high storm surge flooding, coastal erosion and rising sea levels.. Scientists expect a sea level rise of approximately 4 feet or more by 2100 in this area. Coastal resilience tools have estimated billion dollar coasts in damages and interrupted business if preventative tools are not implemented.

Aerial view of Hurricane Sandy from NOAA’s GOES-13 satellite.
Credit: National Geographic

Most communities in the United States were built based on past rather than future trends. But, as storms like Hurricane Sandy devastate communities once thought to be safe, science is playing a key role in informing measures to protect human communities and help people and nature weather the storm.

The North Atlantic Landscape Conservation Cooperative (LCC), Northeast Climate Science Center and U.S. Geological Survey have joined forces on an effort to identify areas along the Atlantic Coast likely to be affected by stronger storms and rising sea levels and areas likely to be the most resilient. Mapping these areas will help inform better management decisions, ranging from preventative action to protection during a storm event. It is likely that more storms like Sandy are heading this way, so it only makes sense to learn from past experiences and plan for the future.

Destinations like Cape Cod and Long Island are bound to change. Residents are likely to see their backyards disappearing and the walk to the beach becoming shorter, some areas sooner than others. The question is not IF anymore, but when.

Our job now is to adapt, plan, and prevent.