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Dr. Alexa McKerrow

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The Species Richness Maps included here are based on the Gap Analysis Project (GAP) habitat maps, which are predictions of the spatial distribution of suitable environmental and land cover conditions within the United States for individual species. Individual species habitat distribution models were summed to create the total richness for each vertebrate taxa. The summing process was coded in Python 2.7 and employed the arcpy module for geoprocessing steps. The code is documented in the log file which is included in the Sciencebase item along with the richness data for each taxa (See processing steps for file names and sciencebase urls). Mapped habitat distribution areas represent places where the environment is...
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The Species Richness Maps included here are based on the Gap Analysis Project (GAP) habitat maps, which are predictions of the spatial distribution of suitable environmental and land cover conditions within the United States for individual species. Individual species habitat distribution models were summed to create the total richness for each vertebrate taxa. The summing process was coded in Python 2.7 and employed the arcpy module for geoprocessing steps. The code is documented in the log file which is included in the Sciencebase item along with the richness data for each taxa (See processing steps for file names and sciencebase urls). Mapped habitat distribution areas represent places where the environment is...
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GAP species range data are coarse representations of the total areal extent a species occupies, in other words the geographic limits within which a species can be found (Morrison and Hall 2002). These data provide the geographic extent within which the USGS Gap Analysis Project delineates areas of suitable habitat for terrestrial vertebrate species in their species' habitat maps. The range maps are created by attributing a vector file derived from the 12-digit Hydrologic Unit Dataset (USDA NRCS 2009). Modifications to that dataset are described here. Attribution of the season range for each species was based on the literature and online sources (See Cross Reference section of the metadata). Attribution for each...
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Gap Analysis Project (GAP) habitat maps are predictions of the spatial distribution of suitable environmental and land cover conditions within the United States for individual species. Mapped areas represent places where the environment is suitable for the species to occur (i.e. suitable to support one or more life history requirements for breeding, resting, or foraging), while areas not included in the map are those predicted to be unsuitable for the species. While the actual distributions of many species are likely to be habitat limited, suitable habitat will not always be occupied because of population dynamics and species interactions. Furthermore, these maps correspond to midscale characterizations of landscapes,...
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The Species Richness Maps included here are based on the Gap Analysis Project (GAP) habitat maps, which are predictions of the spatial distribution of suitable environmental and land cover conditions within the United States for individual species. Individual species habitat distribution models were summed to create the total richness for each vertebrate taxa. The summing process was coded in Python 2.7 and employed the arcpy module for geoprocessing steps. The code is documented in the log file which is included in the Sciencebase item along with the richness data for each taxa (See processing steps for file names and sciencebase urls). Mapped habitat distribution areas represent places where the environment is...
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