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Conclusions:Variability in buffer width across a landscape has important effects on landscape discharge. A variable- width buffer retains less material than a uniform-width buffer of equivalent average width.Thresholds/Learnings:
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Synopsis: Prior to European settlement, the Northern Mixed-grass Prairie was a mosaic of wetland, grassland and grass-shrub habitats, with riparian and floodplain forests along major drainages. Even today, the physiographic area can be characterized as being one of the largest still relatively intact grassland landscapes that persist in North America. It is the continent’s most important production area for waterfowl and is the heart of the breeding range for some of North America’s rarest species of grassland birds. A comparison of relative abundance estimates among physiographic areas sampled by the North American Breeding Bird Survey indicates that more than 40% of the world’s population of Baird’s Sparrows,...
Conclusions:This report sets out guidelines intended to provide BCEAG member jurisdictions with a coordinated approach to recommendations regarding the management of human use activities within wildlife corridors and habitat patches in the Bow Valley of Alberta. The guidelines provide an advisory framework for decision making related to wildlife management as well as recommendations for mitigating the negative effects of human activity on wildlife in the region.Thresholds/Learnings:Male and female cougars avoided areas of high human use and where human use levels exceeded 250-500 users per month.
Conclusions:Landscapes dominated by woody vegetation had significantly more patches, smaller patches and patch core areas, more total edge, and higher patch diversity than landscapes dominated by anthropogenic cover types. Results indicate that expanding juniper is exacerbating the fragmentation process initiated by previous human activityThresholds/Learnings:
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Conclusions: In fragmented watersheds, macrohabitat attributes measured at the patch scale were far more effective in predicting trout translocation success than measurements taken at the landscape scale Thresholds/Learnings: As a course filter indicator of cutthroat trout translocation success, the study found that translocations have a greater than 50% chance of fruitful establishment in watersheds >14.7km2 in area. Synopsis: This study aimed to identify stream-scale and basin-scale macrohabitat attributes limiting successful translocation and persistence of native cutthroat trout populations in fragmented landscapes along the Rio Grande. The study developed models of habitat attributes measured at two scales...
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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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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...
Conclusions:Wetlands and riparian zones should be strategically placed in watersheds to optimize nitrogen removal, as, for example, in tile-drained farmlands prone to high concentrations of nitrateThresholds/Learnings:Restoring 10 million hectares of riparian zones and wetlands, representing 3.4% of the Mississippi River basin, would reduce nitrogen in the Mississippi River Basin and its tributaries by an average of 40%
Conclusions:Report presents draft outcomes, indicators, and targets for the Red Deer River Basin in three topic areas: wetlands, riparian areas, and land use. Targets established were based on a detailed literature review, combined with Geographic Information Systems (GIS) queries of existing conditions.Thresholds/Learnings:Specific thresholds for the region include: wetland cover should comprise >7.5% of the watershed; peatland cover should comprise > 6.0% in the upper headwaters; 82% of all riparian areas (variable width) in the watershed should have perennial vegetation cover; 97% of all riparian areas (variable width) in the Upper Headwaters should have perennial vegetation cover
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This report is synthesizes and summarizes major findings from literature relating to the direct and indirect ecological impacts of paved highways on birds. It represents a meta-analysis of contributing factors of road mortality, effects of roadway lighting, traffic noise, traffic volume, and roadway contaminants on bird populations, which may help guide conservation efforts within the Yellowstone to Yukon ecoregion. Traffic volume and noise are believed to be the most important factors affecting breeding bird population densities near roads. The number of affected species increases with traffic volume but the relationship appears to reach threshold at an average daily traffic volume of 30,000 vehicles a day. In...
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Conclusions: Report presents a framework for assessing the condition of Southern Alberta’s natural assets and their ability to provide ecosystem goods and services. Measurable indicators of ecosystem services, including broad and fine scale landscape indicators, were also distilled from a literature review. Thresholds/Learnings: Wetland cover should be maintained at >15% for watersheds with high potential for phosphorus loading & eutrophication. Impervious cover should be maintained at or below 25% in heavily urbanizing watersheds. Synopsis: This report develops a framework for assessing the condition of Southern Alberta’s natural assets and their resulting ability to provide ecosystem goods and services. The...
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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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Synopsis: Remotely sensed data and GIS were used to compare the effects of clear-cutting and road-building on the landscape pattern of the Bighorn National Forest, Wyoming. Landscape patterns were quantified for each of 12 watersheds on a series of four maps that differed only in the degree of clear-cutting and road density. Researchers analyzed several landscape pattern metrics for the landscape as a whole and for the lodgepole pine and spruce/fir cover classes across the four maps to determine the relative effects of clear-cutting and road building on the pattern of each watershed. At both the landscape and cover class scales, clear-cutting and road building resulted in increased fragmentation as represented...
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Synopsis: Reviews information on grassland bird habitat requirements including a focus on the importance of grassland cover, size of contiguous patches, and other landscape factors. Some species require large blocks of unbroken grassland habitat for nesting. In general, where large blocks of undisturbed grassland occur, grassland birds are able to fulfill most of their requirements during the nesting season. For many bird species, these habitats provide winter and migration cover as well. The more grassland available in an area, particularly in large unbroken blocks, the greater the number of area-sensitive grassland birds the area is able to support. Pastures and crop fields also often provide attractive cover...
Conclusions:Landscape features affect rates of brood parasitism. Rates of parasitism correlate with proximity to woody vegetation along patch edges. Influx of woody vegetation is associated with roadsides and grazing.Thresholds/Learnings:
Conclusions:distance from edge and the habitat heterogeneity were the most important variables affecting bryophyte and lichen species richnessThresholds/Learnings:Temperature and light intensity decreased, and humidity increased up to 15m from the edge of fragments in the study.
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Synopsis: Recensuses of 54 Wisconsin prairie remnants showed that 8 to 60 percent of the original plant species were lost from individual remnants over a 32- to 52-year period. The pattern of species loss was consistent with the proposed effects of fire suppression caused by landscape fragmentation. Short, small-seeded, or nitrogen-fixing plants showed the heaviest losses, as did species growing in the wettest, most productive environments. The interruption of landscape-scale processes (such as wildfire) by fragmentation is an often overlooked mechanism that may be eroding biodiversity in many habitats around the world. Conclusions: Fragmentation may interrupt landscape-scale processes, such as fire, that are key...
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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...
Synopsis: This paper aimed to quantify the relative importance of habitat area and configuration, as well as the contrast in resistance between habitat and non-habitat, on genetic differentiation patterns. Using spatially explicit, individual-based simulation modeling, researchers found that habitat configuration had stronger relationships with genetic differentiation than did habitat area. The pattern of habitat in a landscape will affect the distribution of the population and the degree of connectivity across it, resulting in differential patterns of gene flow. Researchers also evaluated the predictive ability of six widely used landscape metrics and found that patch cohesion and correlation length of habitat...
Synopsis: One recent study examining Eurasian watermilfoil (Myriophyllum spicatum L., hereafter milfoil) invasions using landscape-level variables found that the amount of forest land cover in the catchment is consistently negatively related to milfoil presence (Buchan and Padilla, 2000). These results suggest that further research is needed to examine the relationships between natural and anthropogenic landscape features and macrophyte cover. The ability of lake and landscape features to predict a variety of macrophyte cover metrics using 54 north temperate lakes were examined. Univariate regression analyses demonstrated that these macrophyte cover metrics are predicted by a wide range of predictor variables, most...


map background search result map search result map Effects of paved roads on birds: a literature review and recommendations for the Yellowstone to Yukon Ecoregion Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Minimum habitat requirements for establishing translocated cutthroat trout populations. Ecosystem Goods and Services Southern Alberta Assessment of Natural Asset Condition Assessing the influence of resource co-variates at multiple spatial scales: an application to forest-dwelling caribou faced with intensive human activity. Grassland Birds Gray wolf response to refuge boundaries and roads in Alaska. Watershed analysis of forest fragmentation by clearcuts and roads in a Wyoming forest Ecological determinants of species loss in remnant prairies. Partners in Flight Bird Conservation Plan for Northern Mixed-Grass Prairie American Badger. Assessing the influence of resource co-variates at multiple spatial scales: an application to forest-dwelling caribou faced with intensive human activity. Minimum habitat requirements for establishing translocated cutthroat trout populations. Gray wolf response to refuge boundaries and roads in Alaska. Ecological determinants of species loss in remnant prairies. Watershed analysis of forest fragmentation by clearcuts and roads in a Wyoming forest Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Ecosystem Goods and Services Southern Alberta Assessment of Natural Asset Condition Partners in Flight Bird Conservation Plan for Northern Mixed-Grass Prairie Effects of paved roads on birds: a literature review and recommendations for the Yellowstone to Yukon Ecoregion Grassland Birds