Owning and maintaining waterfront property can be an expensive commitment. Residents across the Chesapeake Bay watershed must contend with shoreline erosion and rising sea level, while adapting to environmental regulations that protect water quality. One strategy for tackling all of these issues has gained increasing popularity: living shorelines that not only protect human property, but also utilize and even enhance the Bay’s unique natural habitat.
Scott Hardaway and Karen Duhring are marine scientists and living shoreline experts at the Virginia Institute of Marine Science (VIMS), which sits at the mouth of the York River in Gloucester Point, Va.
Scott Hardaway began working for VIMS in 1979, and is now the director of the Shoreline Studies Program. He is a leading authority on the design and implementation of “headland breakwaters,” a living shoreline technique that creates protected “pocket beaches” like those constructed at VIMS in 2010.
Headland breakwater systems are built using large stone structures called “headlands,” which sit offshore and disrupt the incoming waves that can cause shoreline erosion. Mathematical formulas determine the necessary angle, shape and placement of each headland. Wider gaps between breakwaters create long, narrow pocket beaches, while narrow gaps create wide, circular beaches.
Their wave-blocking action creates a calm, shallow lagoon between the breakwaters, which are connected to shore by a sandbar called a “tombolo.”
Additional sand must be brought in to form the tombolo and stabilize the beach. This raises the cost of these projects, but is critical to the final phase of construction: planting native beach and dune vegetation.
Karen Duhring is an educator and researcher at the VIMS Center for Coastal Resources Management (CCRM), where she helps manage and monitor living shoreline projects.
According to Duhring, on-shore plantings serve key ecological functions that enhance the effectiveness of living shorelines. On sandy beaches, plant roots stabilize loose material and improve water quality, as they filter pollutants from upland runoff.
Living shorelines use native plants—smooth and saltmeadow cordgrass here in the Bay—that have adapted to thrive and reproduce in a specific environment. Once established, cordgrass recruits naturally along the beach, dispersing seeds and rhizomes that spread horizontally beneath the sand to establish new plants in empty areas.
Beach plantings are susceptible to damage from foot traffic, so precautions should be taken to prevent the trampling of plants. Access restrictions allowed for more expensive plantings on the VIMS western shore, while heavy use from research activities limited plantings on the other.
During high tides, organic material washes onto the beach and provides nutrients for the growing plants, which in turn provide habitat and food for native wildlife.
Headland breakwaters themselves also provide habitat for crabs, mollusks and other aquatic species that thrive on underwater reefs. Along the VIMS shoreline, oysters have settled on the granite rocks to form the beginnings of a complex reef community.
According to Hardaway, headland breakwaters are not always the perfect solution for every sandy shoreline. Whenever possible, existing habitat for submerged aquatic vegetation and shellfish should remain undisturbed. While the costly structures do come with some tradeoffs, they also offer invaluable protection for human infrastructure. The once-vulnerable VIMS shoreline, for instance, has withstood Hurricanes Irene and Sandy—thanks to its headland breakwaters.
As the living shorelines at VIMS demonstrate, projects such as these—which successfully address the needs of both humans and nature—are critical to Bay restoration. Through the work of experts like Hardaway and Duhring, these living shorelines continue to serve both practical and educational purposes, teaching the public how we can responsibly manage our natural resources today in order to preserve them long into the future.
View full-resolution photos on the Chesapeake Bay Program Flickr page.
The federal agencies leading the watershed-wide effort to restore the Chesapeake Bay have released a progress report highlighting the work that was completed last year.
Federal agencies and state and local partners have added 20 new monitoring stations to the Bay and its tributaries, expanding their ability to track changes in water quality and pollution. They have established conservation practices across Bay farms and forests, installing streamside fencing to keep livestock out of waterways and planting cover crops to reduce the need for nutrient-laden fertilizers. And they have planted close to 100 acres of oyster reefs in a Maryland tributary and opened more than 30 miles of Virginia and Pennsylvania streams to eels, shad and other diadromous fish, restoring habitat for some of the watershed’s most critical critters.
But much remains to be done, and the Federal Leadership Committee for the Chesapeake Bay has outlined future work in a 2013 action plan.
“EPA and our other federal partners are pleased to report the tangible progress we’ve made over the past year, which will inform, guide and accelerate our collective actions going forward,” said EPA’s Nick DiPasquale, Chesapeake Bay Program Director. “The federal agencies and our partner jurisdictions are accountable to the citizens living near the local rivers and streams that also stand to benefit from this critical restoration work. Through our commitments, the prospects for increased momentum and improvements to the Bay’s health should be encouraging to everyone.
Harris Creek is a tributary of the Choptank River. Located on Maryland’s Eastern Shore, the waterway has been thrust into the spotlight as the first target of the oyster restoration goals set forth in the Chesapeake Bay Executive Order: to restore oyster populations in 20 Bay tributaries by 2025. Existing reefs will be studied, bars will be built, larvae will be raised and spat-on-shell will be planted in this federally mandated attempt to boost populations of the native bivalve.
Already home to productive and protected oyster reefs, Harris Creek’s good water quality and moderate salinity should allow for high rates of reproduction and low rates of disease—both critical factors in ensuring oyster survival. Indeed, natural “spat set,” or the settling of wild oysters on reefs, was observed in Harris Creek last year, and continued natural spat set could reduce the number of hatchery-raised oysters that are needed to complete the restoration plan.
Over the past two centuries, oyster populations across the Bay have experienced a dramatic decline. Habitat loss, disease and historic over-harvesting have taken their toll, and populations now stand at less than one percent of historic levels. But as filters of water and builders of reef habitat, oysters are critical to the health of the Bay.
As of December 2012, reef construction and seeding for more than a quarter of Harris Creek’s 377 targeted acres were complete, and partners project that more than half of the construction and seeding for the rest of the creek’s reefs will be complete by the fall of 2013.
But it will take a lot for a reef and a tributary to be deemed “restored.” Partners will look not just for the presence of oysters, but for the expansion of oyster populations in the years following restoration efforts. The goal is an ambitious one, but many believe the Harris Creek project will serve as a model for the restoration of other tributaries in support of the Executive Order goal.
Video produced by Steve Droter.
This winter saw an increase in waterfowl along Maryland’s Chesapeake Bay shoreline and Atlantic coast.
While pilots and biologists from the U.S. Fish and Wildlife Service (USFWS) and Maryland Department of Natural Resources (DNR) counted fewer diving and dabbling ducks this winter than they did in the 2012 Midwinter Waterfowl Survey, these same crews counted more geese.
According to a DNR news release, both Canada geese and snow geese were “noticeably more abundant during this year’s survey,” with crews counting 462,000 Canada geese—a three-year high—and 83,300 snow geese—a five-year high. Biologists have attributed the boost in goose numbers to two factors: last spring’s successful nesting season and December snow cover in New York and southern Canada, which encouraged geese to migrate into the Bay region right before the survey was taken.
While more geese could mean more damage to area farms—as the birds forage on green cover crops and grain crops—most farmers “have learned to deal with the problem,” said Larry Hindman, wildlife biologist and Waterfowl Project Leader with DNR. Fluttering plastic flags, bald eagle effigies placed in the middle of fields and the loud bang of a rifle or shotgun have all proven effective at deterring persistent geese, Hindman said, and those farmers who need extra help can find assistance and advice in the U.S. Department of Agriculture’s Wildlife Damage Management program.
Resident Canada geese can pose a problem for rural, suburban and urban residents alike, and are considered overabundant in the region. While the birds do provide hunters with a chance for recreation, resident geese can overgraze wetlands and lawns and leave their droppings to pollute local rivers and streams. While the Midwinter Waterfowl Survey does not make a distinction between resident and migratory geese—as both stocks look the same during an aerial survey—DNR researchers do monitor the resident population using leg bands recovered from hunters.
The Midwinter Waterfowl Survey is used as an index of long-term wintering waterfowl trends. The estimates measure waterfowl populations along the Atlantic Flyway, which is a bird migration route that follows North America’s Atlantic Coast and Appalachian Mountains.
Read the full waterfowl survey results on the DNR website.