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Mosquito ditches are a prolific physical feature of Atlantic coast salt marshes, dug most intensely since the 1930s to control the breeding of salt marsh mosquitoes. Removal of ditches by filling or other methods is under consideration as a restoration alternative at a Fire Island, New York, salt marsh. This study evaluated sediment dynamics and marsh landscape structure of the ditched marsh, thereby providing information to better support efforts to predict marsh responses to restoration alternatives. Field surveys, historic and recent aerial photography analysis, and radiometric dating techniques were used. The estimated average natural sedimentation rate within the ditches was 0.52 cm y-1, a rate greater than the accretion rate of the adjacent marsh surface. The average time for a Fire Island ditch to naturally fill would be 175 years from present, but spatially this is highly variable, with some ditches completely filled and others showing no evidence of natural filling. Active filling of ditches may be a feasible restoration alternative, pending the findings of pilot studies, but given concerns for marsh submergence with accelerated rates of sea level rise, restoration design should provide a hydrologic network to facilitate adequate marsh drainage. [ABSTRACT FROM AUTHOR]

We designed a novel gear to quantitatively sample nekton (free-swimming fish and crustaceans) from salt-marsh ditches and small tidal creeks. This gear, the ditch net, is portable and inexpensive to manufacture, and many replicate samples can be simultaneously collected. The ditch net can sample ditches and tidal creeks as narrow as 25 cm and up to 1 m wide (or wider if the design is modified). The net is suspended between four stakes and covers a 1-m length of ditch bottom. To sample nekton, the mesh doors on both ends of the ditch net are raised, thus enclosing a known area of water and trapping nekton within the net. Catch efficiency of the ditch net was comparable with the actual density of fish traversing the ditch as estimated from video data. Recovery efficiency of the gear was high (99%), indicating that fish rarely escape after the net is triggered. A power analysis indicated that a sample size of 20 provided good power (>0.80 at an alpha level of 0.05) to detect temporal or site differences in nekton community composition. [ABSTRACT FROM AUTHOR]

Hydrologic restoration of Hatches Harbor, a tide-restricted marsh on Cape Cod (Massachusetts), has resulted in significant plant community changes 7 years following the reintroduction of seawater. Since 1999, incremental increases in flow through a tide-restricting dike have facilitated the rapid decline of salt-intolerant vegetation, while encouraging the expansion of native salt marsh taxa. These changes show strong spatial gradients and are correlated with marsh surface elevation, distance from the point of seawater entry, and porewater salinity. Common reed ( Phragmites australis) has not decreased in abundance but has migrated a considerable distance upslope. In the wake of this retreat native halophytes have proliferated. Now that maximum flow through the existing dike structure has been reached, continued recovery may be limited less by changing physicochemical conditions and more by rates of growth, seed dispersal, and seed germination of salt marsh taxa. [ABSTRACT FROM AUTHOR]

The article discusses the contributions of Jim Allen as coastal geomorphologists at the U.S. National Park Service. Allen devoted his career in scientific inquiry, evaluation of management actions and activities, conservation of coastal national parks' heritage. He is considered as an expert in causes and forecasts of shoreline change, beach/dune dynamics, historical alterations, coastal habitat and evolution of geographical information system. His efforts have tremendous impact on coastal parks in the eastern U.S.

This section presents an overview of the natural resources of the Boston Harbor Islands National Park area in Massachusetts. Boston Harbor Islands national park area includes 34 discrete islands and peninsulas, ranging in size from small rock outcrops to Worlds End, a complex of woodland, grassland, freshwater and coastal wetlands, and intertidal habitats. All of the islands have a rich history of human use; many islands have structures, and some islands are still occupied with institutional uses. These various landforms, the interface of marine and terrestrial environments and past land use within an urban region all contribute to a diversity of habitats found throughout the islands. Administratively, the Boston Harbor Islands were designated by the U.S. Congress as a national park in 1996.

Abstract Tidal flow to salt marshes throughout the northeastern United States is often restricted by roads, dikes, impoundments, and inadequately sized culverts or bridge openings, resulting in altered ecological structure and function. In this study we evaluated the response of vegetation and nekton (fishes and decapod crustaceans) to restoration of full tidal flow to a portion of the Sachuest Point salt marsh, Middletown, Rhode Island. A before, after, control, impact study design was used, including evaluations of the tide-restricted marsh, the same marsh after reintroduction of tidal flow (i.e., tide-restored marsh), and an unrestricted control marsh. Before tidal restoration vegetation of the 3.7-ha tide-restricted marsh was dominated by Phragmites australis and was significantly different from the adjacent 6.3-ha Spartina -dominated unrestricted control marsh (analysis of similarities randomization test, p < 0.001). After one growing season vegetation of the tide-restored marsh had changed from its pre-restoration condition (analysis of similarities randomization test, p < 0.005). Although not similar to the unrestricted control marsh, Spartina patens and S. alterniflora abundance increased and abundance and height of Phragmites significantly declined, suggesting a convergence toward typical New England salt marsh vegetation. Before restoration shallow water habitat (creeks and pools) of the unrestricted control marsh supported a greater density of nekton compared with the tide-restricted marsh (analysis of variance, p < 0.001), but after one season of restored tidal flow nekton density was equivalent. A similar trend was documented for nekton species richness. Nekton density and species richness from marsh surface samples were similar between the tide-restored marsh and unrestricted control marsh. Fundulus heteroclitus and Palaemonetes pugio were the numerically dominant fish and decapod species in all sampled habitats. This study provides an example of a... [ABSTRACT FROM AUTHOR]

Abstract Assessing the response of salt marshes to tidal restoration relies on comparisons of ecosystem attributes between restored and reference marshes. Although this approach provides an objective basis for judging project success, inferences can be constrained if the high variability of natural marshes masks differences in sampled attributes between restored and reference sites. Furthermore, such assessments are usually focused on a small number of restoration projects in a local area, limiting the ability to address questions regarding the effectiveness of restoration within a broad region. We developed a hierarchical approach to evaluate the performance of tidal restorations at local and regional scales throughout the Gulf of Maine. The cornerstone of the approach is a standard protocol for monitoring restored and reference salt marshes throughout the region. The monitoring protocol was developed by consensus among nearly 50 restoration scientists and practitioners. The protocol is based on a suite of core structural measures that can be applied to any tidal restoration project. The protocol also includes additional functional measures for application to specific projects. Consistent use of the standard protocol to monitor local projects will enable pooling information for regional assessments. Ultimately, it will be possible to establish a range of reference conditions characterizing natural tidal wetlands in the region and to compare performance curves between populations of restored and reference marshes for assessing regional restoration effectiveness. [ABSTRACT FROM AUTHOR]

BSTRACT Wetland protection regulations and guidelines often require the delineation of precise wetland boundaries on a case-by-case basis. In this study, conducted in the New Jersey Pinelands, an ecological characterization of vegetation composition, soil and hydrologic relationships along upland to wetland Pinus rigida - dominated transittions provided the basis for a multiparameter approach to wetland boundary delineation. The transitional data set was analyzed by direct gradient analysis, cluster analysis and ordination. It is concluded that vegetation composition can be a principal factor in delineating wetland boundaries along natural upland to wetland transitions. However, where distinct vegetation changes are not observed, a feature of our study sites, a multiparameter approach should be used. [ABSTRACT FROM AUTHOR]

Geographic signatures are physical, chemical, biotic, and human-induced characteristics or processes that help define similar or unique features of estuaries along latitudinal or geographic gradients. Geomorphologically, estuaries of the northeastern U.S., from the Hudson River estuary and northward along the Gulf of Maine shoreline, are highly diverse because of a complex bedrock geology and glacial history. Back-barrier estuaries and lagoons occur within the northeast region,but the domiant type is the drowned-river valley, often with rocky shores. Tidal range and mean depth of northeast estuaries are generally greater when compared to estuaries of the more southern U.S. Atlantic coast and Gulf of Mexico. Because of small estuarine drainage basins, low riverine flows, a bedrock substrate, and dense forest cover, sediment loads in northeast estuaries are generally quite low and water clarity is high. Tidal marshes, seagrass meadows, intertidal mudflats, and rocky shores represent major habitat types that fringe northeast estuaries, supporting commercially-important fauna, forage nekton and benthos, and coastal bird communities, while also serving as links between deeper estuarine waters and habitats through detritus-based pathways. Regarding land use and water quality trends, portions ofthe northeast have a history of over a century of intense urbanization as reflected in increased total nitrogen and total phosphorus loadings to estuaries, with wastewater treatment facilities and atmospheric deposition being major sources. Agricultural inputs are relativelyminor throughout the northeast, with relative importance increasing for coastal plain estuaries. Identifying geographic signatures provides an objective means for comparing the structure, function, and processes of estuaries along latitudinal gradients. [ABSTRACT FROM AUTHOR]