Stewardship priorities focus on upland and intertidal resource management issues. Upland development, invasive species, resource use, habitat alteration and climate change are the major drivers to ecological change in the Great Bay estuary. The Reserve strives to protect the integrity of the estuarine system and its watershed by incorporating science and stewardship into management decisions that impact the natural resources. Community involvement is an important component to achieving this goal.
As a founding member of the Great Bay Resource Protection Partnership, the Reserve has taken a lead in land protection to reduce the ecological impacts of habitat fragmentation caused by development in the watershed. The Reserve has a management interest in 3,740 acres of uplands distributed over 71 parcels. Properties are managed to protect threatened species and sustain fish and wildlife populations in balance with human uses.
Stewardship activities are structured experimentally when possible so that their outcomes can be evaluated and used to guide management actions beyond Reserve properties. Myriad efforts are underway to minimize local impacts of population growth and land use change with the goal of sustaining a healthy Great Bay watershed and estuary. Key strategies include conserving undeveloped land, encouraging low impact development approaches, and controlling invasive species.
As climate change proceeds, coastal New Hampshire is likely to experience warmer temperatures and increased flooding from storm events and sea level rise. These changes have substantial implications for the Great Bay ecosystem, as species and habitats may shift in response to changes in temperature and water levels. In addition, human communities in the Great Bay watershed will be affected by increases in the magnitude and frequency of flood events due both to sea level rise and increased precipitation.
Great Bay Reserve's stewardship program is working to anticipate and assess ecological impacts due to climate and sea level change. Comprehensive mapping of salt marsh habitats along with distribution of tidal creeks, pools, and panes will allow us to track vegetative change and associated impacts in this habitat most immediately impacted by any change in sea level. The Reserve is also working with the University of New Hampshire's Jackson Estuarine Lab to place sediment elevation tables (SETs) in several salt marshes throughout the estuary. These instruments will allow scientists to measure future water levels in the marshes.
Establishment of long-term datasets of habitat characterization and other vertical control infrastructure allow Great Bay Reserve's lands to be a site-based living laboratory for research to further our understanding of our changing estuarine environment.
Maintaining the diverse and productive biological communities in the Great Bay estuary is a top priority of the Reserve and Fish and Game. In partnership with other agencies and organizations, the Reserve helps advance multifaceted efforts to protect and restore habitats and species with an emphasis on estuarine habitats such as seagrass beds and salt marshes, and species such as horseshoe crabs and marsh birds. The Reserve also has developed performance indicator monitoring protocols for evaluating the effectiveness of small-scale restoration projects.
Reserve lands are managed as Wildlife Management Areas per the rules and regulations set forth by Fish and Game and approved by the NH Legislature. Through the Great Bay Partnership, the Reserve is working with The Nature Conservancy to complete detailed resource inventories on our properties. From these inventories, we are able to prepare management abstracts that are consistent with the guidelines for a Wildlife Management Area and goals of the Partnership.
All lands unless posted otherwise are open to the public for non-motorized uses including hunting and fishing. Visitor use impacts are quantitatively assessed and key issues addressed in order to balance public enjoyment with maintenance of our native biological communities. The Reserve also developed a sensitive habitats co-occurrence model to guide the location of the Sweet Trail, a regional public access trail in the Crommet Creek watershed.
Conserving land around Great Bay has important implications for rare and endangered species. The Blanding's turtle, an endangered species in New Hampshire, needs large undeveloped landscapes with a diversity of habitat types including freshwater wetlands and vernal pools. Large areas of suitable habitat for Blanding's turtles are concentrated on lands managed by the Reserve.
Several protected properties within the Reserve are managed to protect and create early successional habitat. These areas are required by another endangered species in the state, the New England Cottontail. The return of abandoned agricultural fields to forests has resulted in this habitat type becoming relatively rare. Efforts to protect and restore early successional conditions have direct benefits for New England cottontails as well as other important species that use this habitat.
Bald eagles, a species on the increase, can be found in the winter along the shores of Great Bay. Management of a winter eagle roost site is a top priority for the Reserve. Another species making a strong recovery is the osprey. There are numerous osprey nests within the Great Bay Estuary and the Reserve works with the Project Osprey partnership to help monitor and protect nesting sites.
In addition to changes in the major land uses, invasive species can also substantially affect the structure and quality of habitats in the Great Bay watershed. Invasive species are not native to the region, and they can be introduced through a variety of activities. Clearing land or manipulating habitats creates disturbed conditions under which invasive species thrive. Once invasive species are introduced, they can trigger a series of ecological impacts by outcompeting and eventually replacing native plants. This loss of native species has direct implications for wildlife species that depend on them for food or habitat.
Since 2005, the Great Bay NERR has mapped twenty of the most ecologically damaging invasive plant species on all Reserve properties. Over 4,000 stands of these species have been documented within the Reserve boundary. The most prevalent invasive species include Japanese barberry, common barberry, bush honeysuckle, glossy and common buckthorn, multiflora rose, and autumn olive. Phragmites, or common reed, is the major invasive species in salt marshes, although both native and invasive forms of this plant are present in marshes around Great Bay.
Within the Great Bay NERR, mapping invasive populations has supported strategic prioritization of areas to focus control efforts. By overlaying locations of the most ecologically damaging invasive species and the most ecologically sensitive natural areas, priority areas for removing invasives can be identified. In addition, monitoring and mapping invasive populations enables their early detection before they become prevalent throughout the landscape.
In 2008, the Great Bay NERR began control of Norway maple, purple loosestrife, and black swallowwort. These species were selected for initial control efforts because mapping efforts had determined that only small populations had recently become established within the Reserve. Thus, it was more likely these species could be eradicated without becoming re-established from other nearby populations, thereby increasing the chance they could be removed from within the Reserve for the long term.
In most cases though, invasive species cannot be controlled through isolated efforts. Their aggressive colonization and growth potential requires a management approach that extends across property lines, as eradication of a population on one property does not prevent it from becoming re-established from a population on a neighboring property. For this reason, the Great Bay NERR works closely with local and regional partners to more effectively mitigate the spread of invasive species in the area.
The Great Bay NERR is a key partner in the New Hampshire Coastal Watershed Invasive Plant Partnership (NH CWIPP), which brings together eleven agencies and organizations to assess the extent and control the spread of invasive species in New Hampshire's coastal watershed. Partners in the NH CWIPP work corroboratively to inventory, monitor, and prevent the spread of invasive plants across jurisdictional boundaries. It also works with municipalities, private landowners, and state and federal land managers to control native species and restore native habitats.
In addition, the Reserve promotes and facilitates cooperative invasive species control efforts within its boundary. As an example, the Crommet Creek sub-watershed contains a mix of conservation lands and private properties. Within this watershed, the Great Bay NERR has worked closely with local landowners to document invasive species and build awareness of control options. Through hands-on workshops and demonstration projects, homeowners have learned to identify invasive species and practiced effective ways of removing them.
As the Great Bay NERR's efforts to control invasive species proceed, treatments are being applied using experimental designs that will allow for statistical comparisons of the effectiveness of different control options. By rigorously evaluating the effectiveness of control techniques and tracking conditions that may influence treatment outcomes, efforts by the Great Bay NERR to control invasive species on Reserve properties will provide lessons that are useful beyond its boundary. Ultimately, these experiences will be shared with landowners and management agencies to guide their future decisions about controlling invasive species on private and public lands.
The Stewardship program encourages public participation in managing Reserve lands. Through the Land Stewards program, volunteers monitor properties seasonally and help Reserve staff with management activities such as the removal of trash and debris. To help track illegal dumping as well as the presence of marine debris, the Reserve developed a standardized database to record the type and location of trash.
The Stewardship Coordinator also works closely with the University of New Hampshire instructing Wildlife Management students on how to complete a natural resource inventory and develop management plans. Reserve lands serve as the perfect laboratory for students learning about natural resource management issues.
Great Bay National Estuarine Research Reserve
New Hampshire Fish and Game Department