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NOTE: This download link includes Fish Regions, Freshwater Ecoregions, and Freshwater Resilience. Freshwater ecoregions provide a global biogeographic regionalization of the Earth's freshwater biodiversity. These units are distinguished by patterns of native fish distribution resulting from large-scale geoclimatic processes and evolutionary history. The freshwater ecoregion boundaries generally, though not always, correspond with those of watersheds. Within individual ecoregions there will be turnover of species, such as when moving up or down a river system, but taken as a whole an ecoregion will typically have a distinct evolutionary history and/or suite of ecological processes (Abell et al. 2008). The WWF defined...
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Resilient stream systems are those that will support a full spectrum of biodiversity and maintain their functional integrity even as species compositions and hydrologic properties change in response to shifts in ambient conditions due to climate change. We examined all connected stream networks in the Northeast and Mid-Atlantic for seven characteristics correlated with resilience. These included four physical properties (network length, number of size classes, number of gradients classes and number of temperature classes), and three condition characteristics (risk of hydrologic alterations, natural cover in the floodplain, and amount of impervious surface in the watershed). A network was defined as a continuous...
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The objective of this study was to provide a set of useful condition attributes for perennial stream and river segment in the northeast states (ME, NH, VT, MA, RI, CT, NY, PA, NJ, DE, MD, VA, WV, and DC.). Only perennial streams and rivers with catchments of one square mile or larger as mapped in the NHD Plus 1:100,000 Verson 1 dataset were included in this analysis because smaller streams were too inconsistently mapped. Stream and river reach flowlines were taken from the NHD Plus V1 1:100,000 dataset and tagged with geographic units (watersheds, states, ecoregions) and their simplified stream and river habitat types (23 types) as defined in the "Northeast Habitat Guides: A companion to the terrestrial and aquatic...
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The resistance surface is the basis for the landscape permeability analysis and has a great deal of influence on the final terrestrial landscape resilience scores. As such, great pains were taken to make this dataset as reflective of actual ground condition as possible. Each dataset used was evaluated at several locations, and multiple draft versions of the resistance surface were produced until reviewers were satisfied with the data.Each cell has been assigned a value, or weighting, representing it's hardness/ impermeability to species movement and ecological flows. Higher values are more difficult to cross, while lower values are easier. Natural lands are assigned a value of 1, meaning the cost to move across...
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This dataset is a component of a complete package of products from the Connect the Connecticut project. Connect the Connecticut is a collaborative effort to identify shared priorities for conserving the Connecticut River Watershed for future generations, considering the value of fish and wildlife species and the natural ecosystems they inhabit. Click here to download the full data package, including all documentation. This dataset identifies large and medium rivers within the Connecticut River watershed that provide habitat for five anadromous fish species: American shad, blueback herring, shortnose sturgeon, alewife, and sea lamprey. Habitat includes the mainstem and major tributaries of the Connecticut River...
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We have defined resilience as a function of both a site’s diversity of topoclimates and the site’s ability to support species movement, or terrestrial landscape permeability. Here, we posit that topoclimates provide species localized refugia from the direct effects of a changing climate, whereas landscape permeability reflects the ability of the landscape mosaic to facilitate terrestrial species movement to and between topoclimates as they shift in response to their respective climatic envelopes.90 m topoclimate data, scaled from 0.2 – 1, were multiplied with terrestrial landscape permeability data, scaled from 0 – 1, to generate a resilience value for every 90 m cell across the project area. A full description...
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Note: The download link includes Fish Regions, Freshwater Ecoregions, and Freshwater Resilience. Within each freshwater ecoregion, we defined one to four discrete fish regions using a cluster analysis of the USGS 8-digit Hydrologic Units (HUC) based on similarities in their native fish composition. The analysis was based on a previously developed list of native species present within each HUC (NatureServe, 2008). The cluster analysis defined up to four clusters within each freshwater ecoregion using similarity of composition (Linkage method: Flexible beta, Distance measure: Sorensen (Bray-Curtis), Flexible beta value of -0.250). To determine the faunal distinctiveness between clusters, we performed an indicator...


    map background search result map search result map Stream Reaches for Geospatial Condition Assessment of Northeast Stream and River Habitat Types Freshwater Resilience, All Streams, Stratified by Fish Region and Freshwater Ecoregion, Northeast U.S. Fish Regions, Northeast Freshwater Ecoregions, Northeast Anadromous Fish Index, CT River Watershed Landscape Resistance to Terrestrial Species Movement (90 m) Terrestrial Landscape Resilience to Climate Change (90 m) Anadromous Fish Index, CT River Watershed Stream Reaches for Geospatial Condition Assessment of Northeast Stream and River Habitat Types Freshwater Resilience, All Streams, Stratified by Fish Region and Freshwater Ecoregion, Northeast U.S. Landscape Resistance to Terrestrial Species Movement (90 m) Terrestrial Landscape Resilience to Climate Change (90 m) Fish Regions, Northeast Freshwater Ecoregions, Northeast