Hampton-Seabrook Estuary Habitat Restoration Compendium

The goal of this report is to identify restoration opportunities within the watershed derived from data on habitat change. Many other factors exist that are important in the identification and selection of restoration projects, including water quality and non-point source pollution, water withdrawal, harbor maintenance, recreational impacts, human history, and socioeconomic factors, among others. Although information regarding these factors is not explicitly included in this analysis, these factors must be considered and addressed as they may limit the potential for success in specific restoration effort

Hampton-Seabrook Estuary Restoration Compendium

The Hampton-Seabrook Estuary Habitat Restoration Compendium (HSEHRC) is a compilation of information on the historic and current distributions of salt marsh and sand dune habitats and diadromous fishes within the Hampton-Seabrook Estuary watershed. These habitats and species groups were selected due to the important ecological role they play within the watershed and with effective restoration and conservation efforts, will continue to play. Other ecologically important habitats and species, such as avifauna, shellfish and eelgrass beds, currently are or historically were present within the watershed. Shellfish and seagrass are recognized as important habitats within the Estuary, but were not included in the current report because a different analytical approach may be required for such dynamic and/or short-lived species. A recent report by the New Hampshire (NH) Audubon Society details modern bird use of the Hampton-Seabrook Estuary (McKinley and Hunt 2008). Restoration opportunities have been identified within the watershed by evaluating habitat loss and changes in land use over time. Restoration opportunities are not prioritized in order to allow the goals and objectives of each restoration practitioner to govern project selection. However, in accordance with an ecosystem-based approach to restoration, areas containing multi-habitat restoration opportunities are considered to be of the highest priority. Furthermore, restoration efforts should ensure processes critical for the support of restored components are maintained or reestablished. The goal of this report is to identify restoration opportunities within the watershed derived from data on habitat change. Many other factors exist that are important in the identification and selection of restoration projects, including water quality and non-point source pollution, water withdrawal, harbor maintenance, recreational impacts, human history, and socioeconomic factors, among others. Although information regarding these factors is not explicitly included in this analysis, these factors must be considered and addressed as they may limit the potential for success in specific restoration efforts We present a series of maps detailing changes in the extent of sand dune and salt marsh habitats over time, the current and historic distribution of seven diadromous fish species, and restoration opportunities within the Hampton-Seabrook Estuary and watershed. A narrative describes the methods used, the results of analyses and examples of prominent restoration projects. Each major section concludes with references used in the narrative and maps. The maps are available for viewing as portable document format (.pdf) files. For those with GIS capabilities, the ArcMap 9.2 project files, associated data files and metadata are included on the compact disc as well. The underlying concept and methods for the HSEHRC stem from a previous project conducted within the Great Bay Estuary, the Great Bay Estuary Restoration Compendium (Odell et al. 2006)

Great Bay Estuary Restoration Compendium

Single species approaches to natural resource conservation and management are now viewed as antiquated and oversimplified for dealing with complex systems. Scientists and managers who work in estuaries and other marine systems have urged adoption of ecosystem based approaches to management for nearly a decade, yet practitioners are still struggling to translate the ideas into practice. Similarly, ecological restoration projects in coastal systems have typically addressed one species or habitat. In recent years, efforts to focus on multiple species and habitats have increased. Our project developed an integrated ecosystem approach to identify multi-habitat restoration opportunities in the Great Bay estuary, New Hampshire. We created a conceptual site selection model based on a comparison of historic and modern distribution and abundance data, current environmental conditions, and expert review. Restoration targets included oysters and softshell clams, salt marshes, eelgrass beds, and seven diadromous fish species. Spatial data showing the historical and present day distributions for multiple species and habitats were compiled and integrated into a geographic information system. A matrix of habitat interactions was developed to identify potential for synergy and subsequent restoration efficiency. Output from the site selection models was considered within this framework to identify ecosystem restoration landscapes. The final products of these efforts include a series of maps detailing multi-habitat restoration opportunities extending from upland freshwater fish habitat down to the bay bottom. A companion guidance document was created to present project methods and a review of restoration methods. The authors hope that this work will help to stimulate and inform new restoration projects within the Great Bay estuarine system, and that it will serve as a foundation to be updated and improved as more information is collected

Rethinking the Freshwater Eel: Salt Marsh Trophic Support of the American Eel, Anguilla rostrata

Despite the fact that Anguilla rostrata (American eel) are frequently captured in salt marshes, their role in salt marsh food webs and the influence of human impacts, such as tidal restrictions, on this role remains unclear. To better understand salt marsh trophic support of A. rostrata, eels were collected from tidally restricted and unrestricted salt marsh creeks within three New England estuaries. Gut contents were examined, and eel muscle tissue was analyzed for carbon and nitrogen stable isotope values and entered into MixSir mixing models to understand if salt marsh food sources are important contributors to eel diet. Data suggest that eel prey rely heavily on salt marsh organic matter and eels utilize salt marsh secondary production as an energetic resource over time, and thus can be considered salt marsh residents. Gut contents indicate that A. rostrata function as top predators, feeding primarily on secondary consumers including other fish species, crustaceans, and polychaetes. Higher A. rostrata trophic position measured upstream of reference creeks suggests that severe tidal restrictions may result in altered food webs, but it is not clear how this impacts the overall fitness of A. rostrata populations in New England salt marshes.University of New Hampshire. Sea Grant ProgramUniversity of New Hampshire. Marine Program (William R. Spaulding Endowment

Erosion and Accretion Trends of New Hampshire Beaches from December 2016 to March 2020: Results of the Volunteer Beach Profile Monitoring Program

New Hampshire Atlantic beaches were monitored from December 2016 to March 2020 to determine seasonal changes in morphology and elevation, assess the response of the beaches to storms with respect to erosion and subsequent recovery, and develop a baseline to determine long-term trends in beach size, elevation, and position. A unique aspect of this study was the involvement of community volunteers working together with the University of New Hampshire (UNH) Center for Coastal and Ocean Mapping, UNH Cooperative Extension, New Hampshire Sea Grant, and the New Hampshire Geological Survey. The monitoring network consisted of thirteen stations located at six of the major beaches, including each of the state beaches. Monitoring stations were located at Wallis Sands, Jenness Beach, North Hampton Beach, North Beach, Hampton Beach, and Seabrook Beach. At least two stations were located at each beach (Seabrook Beach had three stations). Beach elevation profiles were run routinely at each station at approximately three- to four-week intervals. Additional measurements were made following several major storms. In total, approximately 400 elevation profiles were run at the thirteen stations. The elevation profiles were run using the Emery (1961) method which utilizes two calibrated rods and the horizon for leveling. Sediment volume calculations were made for each profile that approximated the amount of material in the intertidal zone for that profile at that point in time for a one-meter wide swath of the beach. Seasonal changes and storm impacts on beach elevations, profile characteristics, and sediment volumes are discussed in detail for each beach and the major conditions and processes that control their stability discussed

Evaluation of New England Salt Marsh Support of the American Eel, Anguilla rostrata, and the Impacts of Hydrologic Restriction

American eels are frequently captured in saltmarsh habitats yet little is known about eel use of these systems. Coastal systems such as salt marshes are vulnerable to habitat impacts due to high rates of coastal development, including impacts from undersized culverts that result in tidally restricted systems upstream. Given the decline in the American eel population, a need exists for a clearer understanding of the functional difference of hydrologically restricted and unrestricted salt marshes in the support of eels. To address data gaps and inform saltmarsh management to support eels, laboratory and field experiments were employed that assessed the value of saltmarsh habitats to the life history of the American eel. Eels held in the laboratory were subject to a diet switch to determine the rates at which eel mucus, fin, muscle, and liver tissue assimilate the carbon and nitrogen isotope values of the diet (turnover rate) and the level of discrimination in each tissue relative to the diet (trophic discrimination factors). These data were used to inform the interpretation of data collected from hydrologically restricted and unrestricted creeks in three New England estuaries. Isotope data indicated strong evidence of salt marsh primary producers contributing to the basal diet of eels as well as consumption of marsh resident secondary consumers. Eel gut contents also contained abundant saltmarsh secondary consumers, confirming that eels serve as top predators and are residents in salt marshes. Greater eel trophic position measured upstream of reference creeks indicates that tidal restrictions may result in an altered food web in the tidally restricted marsh. Models were developed for predicting muscle and liver δ15N and δ13C from mucus and fin to provide a non-lethal alternative for sampling yellow eels for stable isotope analysis. Trends in data from a telemetry study suggest that eels released upstream of an undersized culvert with a self-regulating tide gate travelled shorter distances than eels in the reference creeks and had delayed movements to downstream areas of the marsh relative to eels in the reference creek. This study addresses a critical data need for the management of salt marshes to support eels. It provides evidence of eel use of salt marshes as important foraging resources, negative impacts of tidal restriction on trophic support and movement of eels, as well as important data to support future stable isotope analysis of eels. The cumulative impact of marsh loss and degradation, such as through tidal restriction, may be a contributing factor in the decline of eel populations. Conservation and restoration of salt marshes as habitat and management of marshes to maintain ecological integrity will provide critical trophic support and access to essential resources for the American eel population