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Fish occurrence data to support high-resolution distribution models and test various community and macroecological hypotheses have not been available at the national scale. We present IchthyMaps, a database of high-quality historical fish occurrences covering fishes of the conterminous United States. Designed on the principles of metacommunity ecology, IchthyMaps is a compilation of presence records from atlases up to 1990, at the resolution of the 1:100,000 National Hydrography Database Plus (NHDPlus) inter-confluence stream segment, readily aggregated into hierarchically coarser units (e.g. hydrologic unit code 8-digit and 12-digit watersheds). IchthyMaps contains about 606,550 presence records for 1,038 species...
Categories: Data,
Publication;
Types: Citation;
Tags: Alabama,
Arizona,
Arkansas,
Biological Data,
Biological sampling,
Wood load, channel parameters and valley parameters were surveyed in 50 contiguous stream segments each 25 m in length along 12 streams in the Colorado Front Range. Length and diameter of each piece of wood were measured, and the orientation of each piece was tallied as a ramp, buried, bridge or unattached. These data were then used to evaluate longitudinal patterns of wood distribution in forested headwater streams of the Colorado Front Range, and potential channel-, valley- and watershed-scale controls on these patterns. We hypothesized that (i) wood load decreases downstream, (ii) wood is non-randomly distributed at channel lengths of tens to hundreds of meters as a result of the presence of wood jams and (iii)...
Categories: Publication;
Types: Citation,
Journal Citation;
Tags: Colorado Front Range,
Earth Surface Processes and Landforms,
large woody debris,
mountain streams,
spatial distribution,
Conclusions: Reduction in landscape carrying capacity for wolf population distribution and viability depends largely on the degree of road density, public land ownership, amount of forest cover and high elk densities (another indicator of suitable habitat). Synopsis: This study employed two types of spatial models to evaluate the potential of wolf reintroduction in the southern Rocky Mountain region. A multiple logistic regression was used to develop a resource-selection function relating wolf distribution in the Greater Yellowstone region with regional-scale habitat variables. Researchers also used a spatially explicit population model to predict wolf distribution and viability at several potential reintroduction...
Categories: Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: Colorado,
Dynamic models,
Land use configuration,
Landscape fragmentation,
New Mexico,
We studied the associations of crayfish with reach-scale instream habitat and water quality variables and watershed-scale variables of riparian and watershed land cover, runoff, impervious surfaces, and hydrologic soil type in west-central Indiana. Crayfish assemblage was measured by abundance, species richness, and diversity (Shannon's H) at 180 sites. The western portion of the study area, within the Interior River Lowland ecoregion, has been heavily impacted by agriculture, while the eastern portion, within the Interior Plateau ecoregion, is more heavily wooded and less impacted. The ability of variables at each spatial extent to predict crayfish assemblage was assessed using multiple linear regression analysis....
Categories: Publication;
Types: Citation;
Tags: ASFA 1: Biological Sciences & Living Resources,
Abundance,
Agricultural development,
Agriculture,
Biology--Entomology,
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