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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: Few species were in fact influenced by grassland amount or fragmentation. In contrast, distance to edge and local vegetation characteristics had significant effects on densities and nest success of many species. Thresholds/Learnings: Great Plains toads thrive when >75% of the landscape is composed of native prairie components (i.e. shrubs, graminoids, riparian areas, lakes, wetlands, and trees) . Synopsis: In Alberta, Great Plains toads are found in the dry mixed grass of the southeastern corner of the province. Typical breeding habitat tends to be in shallow ponds with relatively fresh, clear water in sandy soil. In this report habitat suitability was evaluated for the Great Plains toad according...
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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...
Conclusions:Stream biotic integrity and habitat quality were negatively correlated with the extent of agriculture and positively correlated with extent of wetlands and forest.Thresholds/Learnings:
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Conclusions: Successional changes resulting from a legacy of fire suppression and other agricultural and access disturbances combine to create the current hetergeneous landscape mosaic. Thresholds/Learnings: Synopsis: Disturbance is considered to be a major factor influencing landscape pattern and vegetation composition. However, the presettlement vegetation composition of three Ohio (U.S.A) counties was controlled largely by soil texture, soil drainage, and topography. In most cases, both disturbance regime and local site conditions can explain presettlement landscape pattern. This study examines the roles of edaphic conditions landscape features such as topography, and fire in contributing to (1) the abundance,...
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Synopsis: The short-horned lizard is Alberta's only lizard. It is indigenous to semi-arid, short grass portions of the northern Great Plains and usually found in rather rough terrain. This report evaluated habitat suitability requirements for the short-horned lizard according to the following parameters: Topographical Features: Most of the daily movement patterns during the summer rarely exceeded 30m, and generally occurred along the slopes of the valleys or valley bottoms. Consequently, all valleys and all prairie habitat within 100m of valleys are considered the best potential habitat. Native Prairie Class: Native Prairie Class (NPC) is derived from the Native Prairie Vegetation Baseline Inventory developed...
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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: Valleys are the only areas capable of sustaining sufficient habitat for the butterfly species, Weidemeyer's Admiral. Consequently, all other areas (i.e. plains, uplands, benches, escarpments, plateaus) were deemed unsuitable. Additionally, areas devoid of shrub cover did not meet the habitat requirements of this specialized species. Thresholds/Learnings: Synopsis: Two variables were selected to model potential habitat for the butterfly species, Weidemeyer's Admiral. Topographical features derived from the Agricultural Region of Alberta Soils Inventory Database (AGRASID) and percent shrub cover derived from the Native Prairie Vegetation Baseline Inventory developed by Alberta Environment were used to...
Conclusions:Native prairie was found to be the most suitable habitat for long-billed curlew. Agriculture lands were used secondarily to varying degrees, and shrublands were considered unsuitable. *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:Shrub coverage greater that 10% was considered undesirable for the long-billed curlew*
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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: The proportion of sage-grouse nests located within 3 vs 5 km suggested that a 5 km buffer around a lek encompassed the majority of nests. The results indicate that land managers should strive to maintain a 5 km buffer around known sage-grouse lek locations in order to ensure sage-grouse breeding success. Thresholds/Learnings: A 5000m buffer around sage-grouse leks encompassed the majority (64%) of sage-grouse nests. Synopsis: This study used radio-telemetry to determine nesting patterns of Greater Sage-Grouse relative to leks in a relatively contiguous sagebrush habitat in Wyoming. The proportion of nests located within 3 vs 5 km suggested that a 5 km buffer around a lek encompassed the majority of...
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Conclusions: At small spatial scales, where extirpation risks are high, landscape fragmentation will likely have long-term negative consequences on the genetic variation of individual assemblages of coastal cutthroat trout. Thresholds/Learnings: Synopsis: This study aimed to determine if coastal cutthroat trout were genetically structured within streams and to assess the effects of habitat fragmentation on coastal cutthroat trout genetic variation. Habitat fragmented by roads and other human disturbances acted as dispersal barriers, which strongly influenced coastal cutthroat trout genetic structure, diversity, and differentiation. At range-wide spatial scales, fragmentation potentially contributes to coastal cutthroat...
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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: 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...
Conclusions: Assessments of metapopulation structure must consider landscape pattern, but also the non-linear responses of organisms to such patterns Thresholds/Learnings: Synopsis: This study used beetles to empirically test the reliability of neutral percolation models to predict critical thresholds of landscape connectivity. Beetle movements declined sharply when grass cover dropped below 20% of the experimental plot. The findings of this study differed from what was predicted by the model, indicating that landscape connectivity is not dependent on spatial pattern alone, but is also highly dependent how individual organisms move within and among patches depending on the amount of cover. The results suggest that...
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: 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...
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Synopsis: This study examined the effect of road improvement and environmental variables on exotic and native plant diversity in roadside verges and adjacent semi-arid grassland, shrubland, and woodland communities of southern Utah. Researchers measured the cover of exotic and native species in roadside verges and both the richness and cover of exotic and native species in adjacent interior communities (50 meters beyond the edge of the road) along 42 roads stratified by level of road improvement (paved, improved surface, graded, and four-wheel drive track). Exotic species richness and cover were more than 50% greater, and the richness of native species 30% lower, at patch interiors adjacent to paved roads than those...
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Synopsis: This study monitored the response of a species of pine bark beetle, Trypodendron lineatum, to direct and indirect measures of habitat availability in a forest subjected to various levels of harvest intensities. Four stand types (conifer dominated, mixed, deciduous dominated, and deciduous dominated with conifer understory) were treated with four levels of harvest intensity (unharvested, 50%, 80%, and 90% harvested). Prior to harvest, the pine bark beetle was most abundant in stands with many host trees (conifer dominated stands). In the first and second summers after harvest, pine beetle abundance increased exponentially with percent spruce cover and the number of spruce stumps in the stand. Beetles were...


map background search result map search result map Great Plains Toad (Bufo cognatus) Weidemeyer's Admiral Distribution of caribou and wolves in relation to linear corridors Influences of barriers to movement on within-watershed genetic variation of coastal cutthroat trout Seasonal distribution and habitat use patterns of elk in the Jack Morrow Hills Planning Area Spatial distribution of greater sage-grouse nests in relatively contiguous sagebrush habitats. Relationships among grizzly bears, highways, and habitat in Banff-Bow Valley, Alberta, Canada. Richardson's Ground Squirrel. Effects of site, landscape features, and fire regime on vegetation patterns in presettlement southern Wisconsin A fish-based index of biological integrity for assessing river condition in Central Alberta Distribution of bark beetle, Trypodendron lineatum in a harvested landscape Short-horned Lizard Prairie Falcon. Prairie Rattlesnake. Roads as conduits for exotic plant invasions in a semi-arid landscape. Spatial patterns and factors influencing small vertebrate fauna road-kill aggregations. Influences of barriers to movement on within-watershed genetic variation of coastal cutthroat trout Effects of site, landscape features, and fire regime on vegetation patterns in presettlement southern Wisconsin 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 Weidemeyer's Admiral Short-horned Lizard Prairie Rattlesnake. Prairie Falcon. Distribution of bark beetle, Trypodendron lineatum in a harvested landscape A fish-based index of biological integrity for assessing river condition in Central Alberta Distribution of caribou and wolves in relation to linear corridors Spatial patterns and factors influencing small vertebrate fauna road-kill aggregations. Roads as conduits for exotic plant invasions in a semi-arid landscape. Spatial distribution of greater sage-grouse nests in relatively contiguous sagebrush habitats. Great Plains Toad (Bufo cognatus) Richardson's Ground Squirrel.