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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: 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: This paper summarizes significant findings from literature related to the effect of noise on wildlife, emphasizing the effects of road traffic noise on birds. Many studies from the United States and the Netherlands indicate that road noise has a negative effect on bird populations, particularly during breeding season in a variety of species. In this paper, ‘effect distances’—distances at which bird density decreases—are reported at a range of two to three thousand meters from the road. Effect distances tend to increase with traffic density, being the greatest near large, multilane highways. In a study of woodland species, 26 of 43 (60%) were found to show a decrease in population densities with effect...
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:
Conclusions:Generally, mimimum buffer widths may help maintain natural physical and chemical characteristics of resources whereas greater buffer widths may be required to maintain biological components of many wetlands and streams. Fixed width buffers do not consider site-specific conditions, and therefore may not adequately buffer aquatic resources. Variable width buffers, albeit more site specific and effective, are more expensive and offer less predictability for planning purposes.Thresholds/Learnings:Stream buffers should be a minimum of 15 to 30m in width to be effective in protecting the ecological integrity of wetlands and streams.
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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: One of the most important trends in biodiversity is the increase in the number of species as the land area increases. Botanists call this trend the species-area relationship, and it is one of the most dependable rules in biology. Many human activities on the landscape, influence species directly by disrupting their habitat, by removing other organisms upon which they may depend, or by injuring or killing them. Less direct, but in many cases equally as disruptive to the native species of an area, is the introduction of exotic species. In this study, data from published studies on flora over the last two centuries was used to produce contour maps of flora size and percentage of exotic species in North America...
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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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Conclusions: Watersheds with low indices of biotic integrity (IBI) have been heavily developed. The biggest factors contributing to low IBIs were the presence of large dams, introduced fish, and road density. Dams at low to middle elevations had the greatest effect on IBI. Thresholds/Learnings: Dams at low to middle elevations had the greatest effect on IBI. Synopsis: Researchers developed a watershed index of biotic integrity to evaluate the biological health of 100 watersheds in the Sierra Nevada of California. In general, watersheds with low indices of biotic integrity (IBI) have been heavily developed by hydraulic mining, agriculture, and hydroelectric dams. The biggest factors contributing to low IBIs were...
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Synopsis: Researchers analyzed variation in crop pollination services provided by native, unmanaged, bee communities on organic and conventional farms situated along a gradient of isolation from natural habitat. Pollination services from native bees were significantly, positively related to the proportion of upland natural habitat in the vicinity of farm sites, but not to any other factor studied, including farm type, insecticide usage, field size and honeybee abundance. The scale of this relationship matched bee foraging ranges. Stability and predictability of pollination services also increased with increasing natural habitat area. This strong relationship between natural habitat area and pollination services...
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Synopsis: The individual species and aggregate community contributions of native bees to crop pollination are documented, on farms that varied both in their proximity to natural habitat and management type (organic versus conventional). On organic farms near natural habitat, we found that native bee communities could provide full pollination services even for a crop with heavy pollination requirements (e.g., watermelon, Citrullus lanatus), without the intervention of managed honey bees. Agricultural intensification diminished these pollination services by roughly 3- to 6-fold. The decline of native bee pollination services with agricultural intensification resulted in significant reductions in both diversity and...
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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: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: 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: 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: When isolated, larger patch size correlates with higher species density and occurence in area-sensitive grassland birds Thresholds/Learnings: Synopsis: This paper examines the influence of landscape fragmentation and isolation of Conservation Reserve Program (CRP) grasslands on grassland breeding bird populations in the northern Great Plains states. The study explores the relationship between species occurrence and density, and patch size by tracking 15 bird species on 303 restored grassland areas. Locating CRP grassland fields near existing grasslands, or establishing one large CRP field rather than several small fields, benefits area-sensitive grassland bird species. Caveats: Inconsistent findings...
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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...
map background search result map search result map Great Plains Toad (Bufo cognatus) Area requirements of grassland birds: a regional perspective. Weidemeyer's Admiral Distribution of caribou and wolves in relation to linear corridors Changing Patterns in the Number of Species in North American Floras. Synthesis of noise effects on wildlife populations. Spatial distribution of greater sage-grouse nests in relatively contiguous sagebrush habitats. 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. Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review. Effects of site, landscape features, and fire regime on vegetation patterns in presettlement southern Wisconsin Evaluating the biotic integrity of watersheds in the Sierra Nevada, California. Crop pollination from native bees at risk from agricultural intensification The area requirements for an ecosystem serivce: crop pollination by native bee communities in California Prairie Falcon. Spatial patterns and factors influencing small vertebrate fauna road-kill aggregations. 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. Distribution of caribou and wolves in relation to linear corridors Crop pollination from native bees at risk from agricultural intensification The area requirements for an ecosystem serivce: crop pollination by native bee communities in California Evaluating the biotic integrity of watersheds in the Sierra Nevada, California. Spatial patterns and factors influencing small vertebrate fauna road-kill aggregations. Spatial distribution of greater sage-grouse nests in relatively contiguous sagebrush habitats. Great Plains Toad (Bufo cognatus) Area requirements of grassland birds: a regional perspective. Population fragmentation and inter-ecosystem movements of grizzly bears in western Canada and the northern United States. Synthesis of noise effects on wildlife populations. Changing Patterns in the Number of Species in North American Floras. Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review.