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This is an antiquated version of the North American Breeding Bird Survey (BBS) dataset that has been superseded by a more recent release. Unless visitors have a specific need for these archived data, they should return to the Main BBS Dataset Page and choose the most recent data release, as that one will include all BBS data released to date. The 1966-2021 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...
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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...
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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 dataset includes all North American Breeding Bird Survey data collected in Mexico between 2008-2018. These data were used as the basis for all analyses discussed in an associated publication: The North American Breeding Bird Survey in Mexico, 2008-2018 — A Status Report; https:doi.org/10.3133/cir1479. The records include avian point count data for all reported taxa (species, races, and unidentified species groupings). In addition to avian count data, this dataset also contains survey date, survey start and end times, start and end weather conditions, a unique observer identification number, route identification information, and route location information including country, state, and BCR, as well as geographic...
The 1966-2022 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 all birds seen within a quarter-mile (400-m) radius and all birds heard. Surveys begin 30...
This is an antiquated version of the North American Breeding Bird Survey (BBS) dataset that has been superseded by a more recent release. Unless visitors have a specific need for these archived data, they should return to the Main BBS Dataset Page and choose the most recent data release, as that one will include all BBS data released to date. 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...
This is an antiquated version of the North American Breeding Bird Survey (BBS) dataset that has been superseded by a more recent release. Unless visitors have a specific need for these archived data, they should return to the Main BBS Dataset Page and choose the most recent data release, as that one will include all BBS data released to date. The 1966-2018 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...
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This geodatabase 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 of...
This is an antiquated version of the North American Breeding Bird Survey (BBS) dataset that has been superseded by a more recent release. Unless visitors have a specific need for these archived data, they should return to the Main BBS Dataset Page and choose the most recent data release, as that one will include all BBS data released to date. The 1966-2017 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...
This page provides access to antiquated versions of the North American Breeding Bird Survey (BBS) dataset that had been used in earlier analyses. Unless visitors have a specific need for these archived data, they should return to the Main BBS Dataset Page and choose the most recent data release, as that one will include all BBS data released to date. Accessing Historic Data The “Child Items” section below links to the historic data releases. Each archived release had included: all data that had been included in the previous release, plus one subsequent year of data, plus all taxonomic updates, data corrections, and/or other minor adjustments that had occurred in that intervening year Release Schedule The BBS...
This is an antiquated version of the North American Breeding Bird Survey (BBS) dataset that has been superseded by a more recent release. Unless visitors have a specific need for these archived data, they should return to the Main BBS Dataset Page and choose the most recent data release, as that one will include all BBS data released to date. The 1966-2016 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...
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Synopsis: A simulation model, modified from percolation theory, was empirically tested to determine if population distribution patterns correlated with different landscape patterns, for different species across a landscape. Using two grasshopper species in a short-grass prairie of north-central Colorado, the experiment found that the threshold for population aggregation (random to clumped distribution) was differentially affected by dispersal ranges and habitat specialization for habitat generalists and habitat specialists, respectively. Habitat generalists aggregated differentially depending on dispersal abilities. Generalist species with good dispersal abilities aggregated when <35% of the landscape consisted...
In 1998, the Quaker Neck Dam was removed from the Neuse River near Goldsboro, North Carolina, restoring access to more than 120 km of potential main-stem spawning habitat and 1,488 km of potential tributary spawning habitat to anadromous fishes. We used plankton sampling and standardized electrofishing to examine the extent to which anadromous fishes utilized this restored spawning habitat in 2003 and 2004. Evidence of spawning activity was detected upstream of the former dam site for three anadromous species: American shad Alosa sapidissima, hickory shad A. mediocris, and striped bass Morone saxatilis. The percentages of eggs and larvae collected in the restored upstream habitat were greater in 2003, when spring...
This is the primary ScienceBase page for accessing North American Breeding Bird Survey (BBS) data. The BBS project measures bird populations on an annual basis. It has been in operation for more than 50 years, monitors 700+ types of birds, and spans the continent (map at right shows sample locations in red). More information about BBS history, methods, and past and ongoing applications of project data can be found in the "Related External Resources" section below. Accessing the Data The BBS releases its data on an annual basis. The “Child Items” section below provides links to the most recent as well as historic data releases. Each annual release includes all previously released data, plus all subsequent taxonomic...
This page provides access to antiquated versions of the North American Breeding Bird Survey (BBS) dataset. These versions are in an older, legacy format and are presented here under one digital object identifier, doi:10.5066/P9YASED1. Please note that this supersedes two prior identifiers, doi:10.5066/F7Q81B46 (original 1966-2014 release) and doi:10.5066/F71R6NK8 (original 1966-2015 release). Unless visitors have a specific need for these archived data, they should return to the Main BBS Dataset Page and choose the most recent data release, as that one will include all BBS data released to date: www.sciencebase.gov/catalog/item/52b1dfa8e4b0d9b325230cd9. These data were released prior to the October 1, 2016 effective...
    map background search result map search result map Brook Trout Occupancy Modeling in 2012 for the Southern Portion of Their Range (PA and South) Critical thresholds in species responses to landscape structure. Brook Trout Occupancy Modeling in 2012 for the Southern Portion of Their Range (PA and south): ArcGIS Map Package North American Atlas - Populated Places Critical thresholds in species responses to landscape structure. Brook Trout Occupancy Modeling in 2012 for the Southern Portion of Their Range (PA and South) Brook Trout Occupancy Modeling in 2012 for the Southern Portion of Their Range (PA and south): ArcGIS Map Package North American Atlas - Populated Places