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Road features were identified using TIGER line data and those features mapped as freeways, secondary roads and local roads were selected. A moving window analysis was applied, which used a window area of 640 acres to determine the miles of road per 640 acres. Output from the analysis was scored where road density values less than 3 miles/640acres were scored as a 3 (“preferred”) and road density values greater than 3 miles/640acres received a score of 1 (“lower quality”).
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Conclusions: Caribou subpopulation persistence and landscape occupancy depends highly on the degree of forest cover, cover type, and distance from human presence. Thresholds/Learnings: Synopsis: This study evaluates factors influencing the persistence and landscape occupancy of caribou subpopulations in southern British Columbia. Data from 235 radio-collared caribou across 13 subpopulations were used to derive a landscape occupancy index. The index was analyzed against 33 landscape variables including, land cover, terrain, climate, and human influence. At the metapopulation level, the persistence of subpopulations correlated with the extent of wet climate conditions and the distribution of old forests and alpine...
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Road densities derived from the TIGER data were analyzed to determine the relationship between road density and Bald eagle potential suitable habitat. The quality of a HUC in relation to road density was defined as good (3), fair (2), or poor (1). The score indicates the threat level for each attribute. A low score indicates a low threat, a medium score indicates a medium threat, and a high score indicates a high threat to the species. The values for each score were characterized in relation to road density by >10 km/km2 = good, 5-10 km/km2 = fair, and 2 = poor.
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This tabular data set represents select basin characteristics compiled for two spatial components of the NHDPlus version 2 data suite (NHDPlusv2) for the conterminous United States; 1) individual reach catchments and 2) reach catchments accumulated upstream through the river network. The select variables in this data set are parsed out into six different file themes as follows: BASIN_CHAR_XXX_CONUS.txt (where XXX is CAT flowline catchment value, ACC is divergence routed accumulated value, and TOT is total upstream routed accumulated value) contains information on stream slope (percent rise, also referred to as the percent slope), basin slope (percent rise, also referred to as the percent slope), basin area, minimum...
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Road features were identified using TIGER line data and those features mapped as freeways, secondary roads and local roads were selected. A moving window analysis was applied, which used a window area of a square kilometer to determine kilometers of road per square kilometer. Output from the analysis was scored based on the following criteria where road density values less than 0.18km/km2 were scored as a 3 (“preferred”), densities between .18 and 1.0518 km/km2 scored as a 2, and road density values greater than 1.0518km/km2 received a score of 1 (“lower quality”)
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Conclusions: Report describes the development of a multi-metric, fish-based Index of Biological Integrity (IBI) to assess the health of aquatic ecosystems on the Battle River, Alberta. The IBI was highly sensitive to cumulative anthropogenic disturbance. Impaired integrity of fish assemblages was detectable at road densities as low as 0.7km/km2 Thresholds/Learnings: Impaired integrity of fish assemblages was detectable at road densities as low as 0.7km/km2. Synopsis: Report describes the development of a multi-metric, fish-based Index of Biological Integrity (IBI) to assess the health of aquatic ecosystems on the Battle River, Alberta. The IBI was highly sensitive to cumulative anthropogenic disturbance. Impaired...
We attempted a complete review of the empirical literature on effects of roads and traffic on animal abundance and distribution. We found 79 studies, with results for 131 species and 30 species groups. Overall, the number of documented negative effects of roads on animal abundance outnumbered the number of positive effects by a factor of 5; 114 responses were negative, 22 were positive, and 56 showed no effect. Amphibians and reptiles tended to show negative effects. Birds showed mainly negative or no effects, with a few positive effects for some small birds and for vultures. Small mammals generally showed either positive effects or no effect, mid-sized mammals showed either negative effects or no effect, and large...
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Conclusions: Habitat associations of prairie rattlesnakes appear to differ depending on whether snakes are hibernating, foraging, or reproducing. Most rattlesnake hibernacula occur within 4 km of a major river, drainage, or coulee, on relatively gentle slopes, but they migrate as far as 25 km away from dens in summer. High road densities present unfavorable habitat conditions for snakes because they are a significant cause of mortality. *Note that this study generated landscape level models with coarse variables, and the thresholds and values used may not be directly applicable to other areas or for site-specific analysis. Thresholds: Most rattlesnake hibernacula occur within 4 km of a major river, drainage, or...
Conclusions:The occurence of bull trout in mid-boreal stream is negatively related to two metrics of industrial activity: percent forest harvesting and road density. Bull trout abundance was positively related to elevation, and negatively related to stream width, slope, and levels of forest harvesting.Thresholds/Learnings:Timber harvest on up to 35% or more of individual subbasins is projected to result in the extripation of bull trout from up to 43% of stream reaches, especially those that support high densities of bull trout.
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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...
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Road densities derived from the TIGER data were analyzed to determine the relationship between road density and Bald eagle potential suitable habitat. The quality of a HUC in relation to road density was defined as good (3), fair (2), or poor (1). The score indicates the threat level for each attribute. A low score indicates a low threat, a medium score indicates a medium threat, and a high score indicates a high threat to the species. The values for each score were characterized in relation to road density by >10 km/km2 = good, 5-10 km/km2 = fair, and 2 = poor.
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Conclusions: Results offer support for the use of land cover as an indicator of biotic integrity estimated by both vegetation and bird communities. Strong, significant predictions of IBI scores in plant and bird communities were achieved using land cover data from every spatial extent. Plant-based IBI scores were best predicted using data from 100 m buffers and bird-based IBI scores were best predicted using data extracted from 500 m buffers. Road density and measures of the proportion of disturbed land were consistent predictors of IBI score, suggesting their universal importance to plant and bird communities. Thresholds/Learnings: Road effects on bird communities were most pronounced at the 500m spatial extent....
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Synopsis: This study attempts to build a forest fragmentation database for the conterminous United States by utilizing high-resolution NLCD data, roads, and a series of fragmentation indices that quantify forest landscape patterns. The paper outlines a methodology for assessing forest fragmentation and provides a comprehensive data set to be used as a base for further investigation at smaller scales. Conclusions: A forest fragmentation database for the conterminous United States was built to quantify forest landscape patterns nationwide. The paper outlines a methodology for assessing forest fragmentation and provides a comprehensive data set to be used as a base for further investigation at smaller scales. Thresholds/Learnings:...
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Conclusions: Elk habitat selection ratios varied in response to road pattern. Regularly spaced roads negatively influenced habitat selection, whereas a clumped pattern supported larger blocks of road-free habitat. Road density threshold at which elk could still occur in high numbers: 1.5 km/km⊃2; Thresholds/Learnings: Road density threshold at which elk could still occur in high numbers: 1.5 km/km⊃2; Synopsis: This study tested 3 aspects of an elk road density model to determine patterns of elk behavior relative to road density and configuration. The study compared model predictions with observed values of elk habitat selection at varying levels of road density. It also compared the effect of different spatial...
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Road features were identified using TIGER line data and those features mapped as freeways, secondary roads and local roads were selected.A moving window analysis was applied, which used a window area of 640 acres to determine the miles of road per 640 acres. Output from the analysis was scored where road density values less than 3 miles/640acres were scored as a 3 (“preferred”) and road density values greater than 3 miles/640acres received a score of 1 (“lower quality”).
We attempted a complete review of the empirical literature on effects of roads and traffic on animal abundance and distribution. We found 79 studies, with results for 131 species and 30 species groups. Overall, the number of documented negative effects of roads on animal abundance outnumbered the number of positive effects by a factor of 5; 114 responses were negative, 22 were positive, and 56 showed no effect. Amphibians and reptiles tended to show negative effects. Birds showed mainly negative or no effects, with a few positive effects for some small birds and for vultures. Small mammals generally showed either positive effects or no effect, mid-sized mammals showed either negative effects or no effect, and large...
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Synopsis: Species status assessments are often hindered by a paucity of demographic, abundance, or distributional data. Although extinction-risk correlates have been identified, their wide applicability may be compromised by differences in the variables examined, modeling technique, and phylogenetic or distributional scale. Here, we apply a common analytical approach to examine 14 possible extinction-risk correlates for mammals, fishes, and birds throughout Canada. Among mammals, risk is positively and strongly correlated with road density and age at maturity for land animals and weakly with body size for sea dwellers. Delayed maturity is of primary importance to predicting risk status in fishes, with small body...
    map background search result map search result map Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Elk distribution and modeling in relation to roads Forest fragmentation of the coterminous United States: assessing forest intactness through road density and spatial characteristics. Impacts of landscape change on wolf restoration success: planning a reintroduction program based on static and dynamic spatial models. A fish-based index of biological integrity for assessing river condition in Central Alberta The accuracy of land cover-based wetland assessments is influenced by landscape extent. Prairie Rattlesnake. Correlates of Vertebrate Extinction Risk in Canada. Attributes for NHDPlus Version 2.1 Catchments and Modified Routing of Upstream Watersheds for the Conterminous United States: Select Basin Characteristics BLM REA NGB 2011 Road Density near Bald Eagle suitable habitat (GAP) (Winter) BLM REA NGB 2011 Road Density for Modeled Mule Deer Winter and Year long Habitat BLM REA NGB 2011 Road Density Score for Modeled Pronghorn Habitat BLM REA NGB 2011 Road Density near Bald Eagle suitable habitat (GAP) (Summer) BLM REA NGB 2011 Road Density for Modeled Mule Deer Summer and Year long Habitat Elk distribution and modeling in relation to roads Prairie Rattlesnake. The accuracy of land cover-based wetland assessments is influenced by landscape extent. A fish-based index of biological integrity for assessing river condition in Central Alberta Factors influencing the dispersion and fragmentation of endangered mountain caribou populations BLM REA NGB 2011 Road Density for Modeled Mule Deer Winter and Year long Habitat BLM REA NGB 2011 Road Density Score for Modeled Pronghorn Habitat BLM REA NGB 2011 Road Density for Modeled Mule Deer Summer and Year long Habitat BLM REA NGB 2011 Road Density near Bald Eagle suitable habitat (GAP) (Winter) BLM REA NGB 2011 Road Density near Bald Eagle suitable habitat (GAP) (Summer) Impacts of landscape change on wolf restoration success: planning a reintroduction program based on static and dynamic spatial models. Forest fragmentation of the coterminous United States: assessing forest intactness through road density and spatial characteristics. Attributes for NHDPlus Version 2.1 Catchments and Modified Routing of Upstream Watersheds for the Conterminous United States: Select Basin Characteristics Correlates of Vertebrate Extinction Risk in Canada.