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Synopsis: The purpose of this model is to indicate potential habitat for olive-backed pocket mice (Perohnathus fasciatus) within the Milk River Basin. As this is a landscape level model with course variaqbles, it may not be directly applicable to other areas for site-specific analysis. Conclusions: Olive-backed pocket mice require high proportions of grassland habitat and low proportions of shrub cover. Sites with low densities of shrubs are preferred because they provide cover from large and aerial predators, such as owls. A threshold of below 40% shrub coverage represents ideal shrub cover proportions.
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Synopsis: In an attempt to better characterize the influence of human settlement patterns on wolf distribution, this paper examined how radio-collared gray wolves responded to different road types and human presence at the boundaries of Kenai National Wildlife Refuge in south-central Alaska. Wolves tended to avoid oilfield access roads that were open to the public, but were attracted to gated pipeline access roads and secondary gravel roads with limited human use. The low use access and secondary roads likely provided an easy travel corridor for wolves. Prior to intensive trapping and hunting from 1978-1979, wolves demonstrated little territorial adjustment in response to a heavily used highway. However, only after...
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Synopsis: Using multi-scale seasonal models, this study explored how broad scale landscape context and local resource heterogeneity influenced local resource selection among threatened forest-dwelling woodland caribou in southern Quebec. Caribou consistently avoided roads, however researchers identified thresholds in road proximity effects. The threshold distance at which caribou avoid roads is 1.25 km for active roads and 0.75 km from derelict roads. Open lichen woodlands were an important cover type for caribou during winter and spring, whereas deciduous forests, wetlands, and even young disturbed stands became important during calving and summer. Landscape cover type and amount explained more variation in habitat...
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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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Conclusions: Grizzly bears can use roaded habitats, but spatial avoidance will increase and survival will decrease as traffic levels, road densities and human settlement increases. Road density standards and road closure programmes should be developed and that these programmes incorporate seasonal habitat requirements of grizzly bears. Thresholds/Learnings: More than 80% of bear sitings occurred in blocks of undisturbed habitat >900 ha Synopsis: The study examined the relationships between grizzly bears, habitat and roads in the Swan Mountains, Montana. The study showed complex spatial and temporal relationships between grizzly bears and habitat resources. Resource selection was expressed relative to strength...
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Synopsis: This report evaluates habitat requirements of the American badger according to parameters of soil texture, graminoid cover, slope, and proximity to roads. Badgers tend to prefer sandy loam and silty loam, medium and moderately coarse textured soils. In terms of graminoid coverage, badgers generally prefer open grassland habitat, but can also be found in agriculturally dominated landscapes containing isolated pockets of Richardson 's ground squirrel colonies. Graminoid coverage of 23% was chosen as the minimum requirement for suitable badger habitat. As slope increases, habitat suitability decreases to a point at which the likelihood of badgers existing there (i.e. cliffs and badlands) is extremely low...
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Conclusions: Caribou demonstrated patterns of avoidance near linear features such as pipelines, roads, and other oil field structures. Females demonstrated heightened avoidance, especially during calving seasons. Thresholds/Learnings: Synopsis: This study documented the behavioural reactions of caribou to oil development in the circumpolar regions of the northern hemisphere. Researchers observed patterns of avoidance near linear features such as pipelines, roads, and other oil field structures. Female caribou, especially those accompanied by calves avoided these areas in particular. Male caribou were more apt to occupy areas influenced by oil field structures and activity. In summary, the patterns oil field development...
Conclusions:Woodland caribou cross roads less than expected for all time periods except calving and use areas close to roads less frequently than expected. Roads are semipermeable barriers to caribou movement with the greatest barrier effects occurring during late winter.Thresholds/Learnings:
Conclusions:Adult mortality appeared to be largely the result of predation, with cougars accounting for half of the known-cause mortalities. The much higher rate of mortality observed in the more developed portion of the study area supports a link between predation and forestry development.Thresholds/Learnings:
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Conclusions: Grizzly bear population fragmentation corresponded to the presence of settled mountain valleys and major highways. In these disturbed areas, the inter-area movements of female bears was affected more than for male bears. Without female connectivity, small subpopulations of grizzly bears are not viable over the long term. Thresholds/Learnings: Females grizzlies reduced their movement rates drastically when settlement increased to >20% of a given area. In highly settled areas (>50% settlement), both sexes demonstrated similar reductions in movement. Synopsis: Researchers studied the current state and potential causes of population fragmentation in grizzly bears over western Canada, the Greater Yellowstone...
Categories: Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Alberta, British Columbia, Canadian Rockies, Chilcotin Ranges and Fraser Plateau, Clear Hills and Western Alberta Upland, All tags...
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Conclusions: Grizzly bears avoid high volume roads (25,000 vehicles/day). High quality habitat determines movement decisions relative to roads. Grizzly bears will cross high volume roads to access high-quality habitat. Grizzly bears use areas close to roads more than expected, in particular low-volume roads (10,000 vehicles/day). Prevent loss of habitat connectivity with the following mitigation: maintain high-quality habitat adjacent to roads, install continuous highway fencing and create wildlife passages. Thresholds/Learnings: Synopsis: The study examined the relationships among grizzly bears, their habitats and roads in Banff National Park, a protected area characterized by a major transportation corridor. This...
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Conclusions: Despite the fact that valuable grizzly habitat tends to coincide with the location of roads, grizzlies strongly avoided roads regardless of traffic volume, suggesting that even a few vehicles can displace bears from adjacent habitats. Thresholds/Learnings: Grizzlies strongly avoided areas within 100m of all roads Synopsis: This study aimed to determine whether grizzly bears were displaced by roads associated with resource extraction industries in the Rocky Mountains. Since many habitats close to roads contained important bear foods, researchers expected bears to frequent these roads, despite the presence of human activity. However, study results indicated that grizzlies strongly avoided roads regardless...
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Conclusions: The negative effects of patch size and isolation on species may not occur until the landscape consists of less than 10% suitable habitat for birds, and 30% suitable habitat for mammals. Thresholds/Learnings: The negative effects of patch size and isolation on species may not occur until the landscape consists of less than 10% suitable habitat for birds, and 30% suitable habitat for mammals. Synopsis: This study involved a review of studies on birds and mammals in habitat patches in landscapes with different proportions of suitable habitat. The findings demonstrate that there exists a threshold in proportion of suitable habitat in the landscape, above which fragmentation becomes pure habitat loss....
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Synopsis: This study examined the spatial patterns and factors influencing small terrestrial vertebrate road-kill aggregations in the Bow River Valley of Alberta, Canada. Mammal and bird road-kill indices were consistently higher on low volume parkway roads than on the high-speed, high volume Trans-Canada highway (TCH). Birds were more vulnerable to collisions than mammals on the TCH. Low volume parkway road-kills were less likely to occur on raised sections of road, and tended to occur close to vegetative cover far from wildlife passages and culverts. Highway sections with forested medians were less significant barriers to forest birds than open grassy medians. Since forest dwelling birds are reluctant to cross...
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Conclusions: Caribou mortalities attributed to wolf predation were generally closer to a corridor, indicating that linear corridors may enhance wolf predation efficiency. Therefore, caribou existing closer to linear corridors are at a higher risk of depredation than those farther from corridors. Thresholds/Learnings: Synopsis: This study tested the hypothesis that linear corridors affect caribou and wolf activities by examining the distribution of telemetry locations of caribou and wolves, as well as locations of caribou mortality and caribou predation by wolves relative to linear corridors caused by roads, seismic lines, power lines, and pipeline rights-of-way. Caribou mortalities attributed to wolf predation...
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Conclusions: Richardson's ground squirrels prefer short grass native prairie / pasture but can also occupy small isolated islands within cropland. These squirrels prefer open prairies and tend to select against heavily forested areas. *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/Learnings: A threshold amount of 20% graminoid coverage is the minimum suitable proportion for habitat suitability for Richarson's ground squirrel. Areas with less than 20% forest/shrub cover were considered sutiable habitat, while those greater than 40% were considered unsuitable*. ...
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Conclusions: Summarizes findings from a review of literature intended to identify critical thresholds for conservation based in empirical studies of landscape fragmentation. Presents a conceptual overview of landscape fragmentation and habitat loss, as well as guidelines and thresholds relating to landscape indicators such as patch size, habitat amount, edge effects, riparian buffers, and habitat connectivity. Thresholds/Learnings: Many. See Kennedy et al. 2003. Synopsis: This report summarizes findings from a review of literature intended to identify critical thresholds for conservation based in empirical studies of landscape fragmentation. In presenting a conceptual overview of landscape fragmentation and habitat...
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Conclusions: Elk consistently selected for big basin sagebrush, greasewood, and tree cover; and consistently selected against Wyoming sagebrush, mixed shrub, and bare ground/sand. Selection patterns were similar during the winter, except big basin sagebrush and mixed shrubs were selected in proportion to their availability. Elk tend to prefer areas characterized by edge habitat where quality forage and cover habitats are in close proximity to one another. Thresholds/Learnings: Elk use was highest in summer in areas characterized by diverse habitats and >2800m away from major roads. High use areas during winter were similar, although elk tended to use areas slightly closer to roads (>2100m away), which is largely...
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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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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...


map background search result map search result map Caribou in the Changing North Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Distribution of caribou and wolves in relation to linear corridors Conservation Thresholds for Land Use Planners Elk distribution and modeling in relation to roads Seasonal distribution and habitat use patterns of elk in the Jack Morrow Hills Planning Area Assessing the influence of resource co-variates at multiple spatial scales: an application to forest-dwelling caribou faced with intensive human activity. Gray wolf response to refuge boundaries and roads in Alaska. Impacts of landscape change on wolf restoration success: planning a reintroduction program based on static and dynamic spatial models. Population fragmentation and inter-ecosystem movements of grizzly bears in western Canada and the northern United States. Grizzly bears and resource extraction industries: effects of road on behavior, habitat use, and demography. Relationships among grizzly bears, highways, and habitat in Banff-Bow Valley, Alberta, Canada. Relationships among grizzly bears, roads, and habitat in the Swan Mountains, Montana. Richardson's Ground Squirrel. Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review. Olive-backed Pocket Mouse. Spatial patterns and factors influencing small vertebrate fauna road-kill aggregations. American Badger. Elk distribution and modeling in relation to roads Relationships among grizzly bears, highways, and habitat in Banff-Bow Valley, Alberta, Canada. Seasonal distribution and habitat use patterns of elk in the Jack Morrow Hills Planning Area Assessing the influence of resource co-variates at multiple spatial scales: an application to forest-dwelling caribou faced with intensive human activity. Distribution of caribou and wolves in relation to linear corridors Gray wolf response to refuge boundaries and roads in Alaska. Spatial patterns and factors influencing small vertebrate fauna road-kill aggregations. Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Impacts of landscape change on wolf restoration success: planning a reintroduction program based on static and dynamic spatial models. Richardson's Ground Squirrel. Population fragmentation and inter-ecosystem movements of grizzly bears in western Canada and the northern United States. Caribou in the Changing North Conservation Thresholds for Land Use Planners Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review.