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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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The Randomized Shortest Path (RSP) raster delineates potential dispersal paths for male-mediated gene flow between grizzly bear (Ursus arctos) populations in the Greater Yellowstone Ecosystem (GYE) and the Northern Continental Divide Ecosystem (NCDE). A RSP algorithm was used to estimate the average number of net passages for all grid cells at a spatial resolution of 300 m in the study region which spans parts of Montana, Idaho, and Wyoming. RSP rasters identify potential movement paths for 3 levels of random deviation determined by the parameter Θ (i.e., Θ = 0.01, 0.001, and 0.0001) for bears moving from an origin to a destination node. Lower values of Θ result in greater exploration and more random deviation around...
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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: female connectivity, climate change, grizzly bears, Canadian Rockies, Coastal Western Hemlock, 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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For several decades, grizzly bear (Ursus arctos) populations in the Greater Yellowstone Ecosystem (GYE) and the Northern Continental Divide Ecosystem (NCDE) have increased in numbers and range extent. Whereas the NCDE population is contiguous with grizzly bear populations in the Canadian Rocky Mountains, genetic evidence suggests the GYE population remains isolated. Recent analyses indicate the effective population size of GYE grizzly bears has increased and is approaching levels needed for long-term viability. With only ~110 km distance separating current estimates of occupied range for these populations, the potential for immigration into the GYE from an NCDE migrant, or vice versa, is likely greater now than...
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This project will focus on analysis of 10 years of GPS telemetry data for 60 grizzly bears across the threatened and fragmented trans-border grizzly bear subpopulations in the Cabinet, Yaak, Purcell, and Selkirk Mountain (Proctor et al. 2012) with a goal to identify areas of high quality core habitat and understand the ecological characteristics that underpin habitat use. We will use Resource Selection Function habitat-use models for partitioned by sex and in each of 3 seasons to capture the variation of bear habitat use. We will also work to integrate our results to inform wildlife and land managers on where to concentrate their management efforts by season to promote population health and resilience in both the...
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The grizzly bear distribution boundary delineates the estimated geographic extent of occupied range of the Yellowstone grizzly bear population for the period 2000-2014. The distribution boundary was generated to provide reliable estimations of grizzly bear occupancy throughout time and for use as a monitoring tool in grizzly bear management and conservation. The boundary was delineated by the Interagency Grizzly Bear Study Team (IGBST) using an interpolation method based on grizzly bear telemetry and GPS locations as well as verified observations and signs of grizzly bears inside the Greater Yellowstone ecosystem during 2000 to 2014.
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Conclusions: Seismic cutline proportion did not explain landscape use by grizzly bears, but secondary effects of cutlines on landscape structure did. Declining use was mainly associated with increasing proportions of closed forest, and increasing variation of inter-patch distances, while use was mainly increasing with increasing mean patch size. Thresholds/Learnings: Bears appear to use areas more when landscape patches tend to be larger, and mean patch size is generally reduced with additional seismic cutlines. Also, bears appear to use areas more when landscape patches are consistently spaced, and the spacing between landscape patches becomes more variable with additional seismic cutlines. Synopsis: This study...


    map background search result map search result map 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. Seismic cutlines, changing landscape metrics, and grizzly bear landscape use in Alberta Relationships among grizzly bears, roads, and habitat in the Swan Mountains, Montana. Core Habitat Identification and Fine Scale Habitat Use of Grizzly Bears in the US Northern Rockies and Southern Canada Potential movement paths for male grizzly bear (Ursus arctos) dispersal between the Northern Continental Divide and Greater Yellowstone Ecosystems, 2000-2015 Randomized shortest paths for Grizzly Bear dispersal between the GYE and NCDE Distribution of the Yellowstone Grizzly Bear (2000-2014) Relationships among grizzly bears, highways, and habitat in Banff-Bow Valley, Alberta, Canada. Grizzly bears and resource extraction industries: effects of road on behavior, habitat use, and demography. Seismic cutlines, changing landscape metrics, and grizzly bear landscape use in Alberta Relationships among grizzly bears, roads, and habitat in the Swan Mountains, Montana. Distribution of the Yellowstone Grizzly Bear (2000-2014) Core Habitat Identification and Fine Scale Habitat Use of Grizzly Bears in the US Northern Rockies and Southern Canada Potential movement paths for male grizzly bear (Ursus arctos) dispersal between the Northern Continental Divide and Greater Yellowstone Ecosystems, 2000-2015 Randomized shortest paths for Grizzly Bear dispersal between the GYE and NCDE Population fragmentation and inter-ecosystem movements of grizzly bears in western Canada and the northern United States.