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Mark S Boyce

Fragmentation is a growing threat to wildlife worldwide and managers need solutions to reverseits impacts on species’ populations. Populations of grizzly bears (Ursus arctos), often considered an umbrellaand focal species for largemammal conservation, are fragmented by human settlement and major highways inthe trans-border region of southern British Columbia, northern Montana, Idaho, and northeasternWashington. To improve prospects for bear movement among 5 small fragmented grizzly bearsubpopulations, we asked 2 inter-related questions: Are there preferred linkage habitats for grizzly bearsacross settled valleys with major highways in the fragmented trans-border region, and if so, could we predictthem using a combination...
Detailed empirical models predicting both species occurrence and fitness across a landscape are necessary to understand processes related to population persistence. Failure to consider both occurrence and fitness may result in incorrect assessments of habitat importance leading to inappropriate management strategies. We took a two-stage approach to identifying critical nesting and brood-rearing habitat for the endangered Greater Sage-Grouse (Centrocercus urophasianus) in Alberta at a landscape scale. First, we used logistic regression to develop spatial models predicting the relative probability of use (occurrence) for Sage-Grouse nests and broods. Secondly, we used Cox proportional hazards survival models to identify...
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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