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A joint venture involving the National Atlas programs in Canada (Natural Resources Canada), Mexico (Instituto Nacional de Estadística Geografía e Informática), and the United States (U.S. Geological Survey), as well as the North American Commission for Environmental Co-operation, has led to the release (June 2004) of several new products: an updated paper map of North America, and its associated geospatial data sets and their metadata. These data sets are available online from each of the partner countries both for visualization and download. The North American Atlas data are standardized geospatial data sets at 1:10,000,000 scale. A variety of basic data layers (e.g. roads, railroads, populated places, political...
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This ArcGIS Map Package contains information on brook trout occupancy in the southern portion of the brook trout range (PA and south). Fish sample data from a number of state and federal agencies/organizations were used to define patches for brook trout as groups of occupied contiguous catchment polygons from the National Hydrography Dataset Plus Version 1 (NHDPlusV1) catchment GIS layer. After defining patches, NHDPlusV1 catchments were assigned occupancy codes. Then state and federal agencies reviewed patches and codes to verify data accuracy. A similar effort is currently being conducted by the Eastern Brook Trout Joint Venture to develop occupancy data for the remainder of the brook trout range including states...
The 1966-2019 North American Breeding Bird Survey (BBS) dataset contains avian point count data for more than 700 North American bird taxa (species, races, and unidentified species groupings). These data are collected annually during the breeding season, primarily in June, along thousands of randomly established roadside survey routes in the United States and Canada. Routes are roughly 24.5 miles (39.2 km) long with counting locations placed at approximately half-mile (800-m) intervals, for a total of 50 stops. At each stop, a citizen scientist highly skilled in avian identification conducts a 3-minute point count, recording every bird seen or heard within a quarter-mile (400-m) radius. Surveys begin 30 minutes...


map background search result map search result map Brook Trout Occupancy Modeling in 2012 for the Southern Portion of Their Range (PA and south): ArcGIS Map Package North American Atlas - Populated Places Brook Trout Occupancy Modeling in 2012 for the Southern Portion of Their Range (PA and south): ArcGIS Map Package North American Atlas - Populated Places