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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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The metrics used to assess the size of core habitat fragments was developed by considering the average home range for mule deer in the intermountain west. Habitat fragment size does not pertain to the minimum habitat area, but rather reflects landscape fragments that are easily traversed by mule deer as they move between patches of suitable habitat. Using the Habitat Core Area (HCA) toolset developed by WHCWG (2010), large, contiguous core habitat fragments were identified that presented no permeability restrictions and retained high levels of naturalness (i.e., core areas characterized by a relatively light human footprint). Habitat fragments larger than 500 ha were considered good, fragments between 300-500ha...
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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...
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The metrics used to assess the size of core habitat fragments was developed by considering the average home range for mule deer in the intermountain west. Habitat fragment size does not pertain to the minimum habitat area, but rather reflects landscape fragments that are easily traversed by mule deer as they move between patches of suitable habitat. Using the Habitat Core Area (HCA) toolset developed by WHCWG (2010), large, contiguous core habitat fragments were identified that presented no permeability restrictions and retained high levels of naturalness (i.e., core areas characterized by a relatively light human footprint). Habitat fragments larger than 500 ha were considered good, fragments between 300-500ha...
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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: 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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Magnitude of habitat fragmentation indicated by largest patch size, by terrestrial ecoregion. We considered agriculture, urban infrastructure, roads, and railroads as “fragmenting” features to the landscape and areas not converted to agriculture, urban infrastructure, roads, or railroads as “nonfragmented” terrestrial landscape patches. We used input spatial data from JRC’s GLC 2000 (2003), CIESIN et al. (2004), Defense Mapping Agency (1992), and South American Conservation Region (2005). To produce the data, we constructed a global map grid of fragmenting features (Mollweide projection, based on the WGS 1984 datum; 1 km2 resolution); this grid was then combined with the GLC 2000, adding a new “fragmenting features”...
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Habitat size refers to the size of the habitat patch extracted from the WAFWA dataset and is used to characterize the quality of the analysis unit by determining the size of patches and grading them based on size thresholds (>75 km2 is considered good, less than 75 km2 is considered poor).
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Using the patch habitat GIS layer outputs for the pronghorn, the habitat patch layer was classified based on the patch acreage ranges established for this indicator and assigned associated values between 1 and 3. Where a value of ‘1’ represented ‘Lower Quality” (500ha).
Conclusions:Unsuitable habitat surrounding a patch of suitable habitat creates islands of high species density from which successful dispersion becomes difficult. Therefore, habitat surrounding a patch, rather than the quality of the patch itself, may be a more important determining factor of species abundance.Thresholds/Learnings:
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Synopsis: The study examined the effects of road networks on suburbanizing ecosystems, using grassland bird distribution to explore the relative ecological importance of variables relative to linear disturbances and the effect of road traffic volumes. The study found that roads primarily affect ecological variables for 1) distance from road and 2) habitat patch size. The study also found that road traffic volumes are correlated to avian distribution, suggesting that traffic volumes have an ecological effect. The research suggests that traffic noise is the primary ecological effect of roads and that roads with higher traffic volumes extend the road effect zone outwards of 100 m and up to 1,200 m. Given the ecological...
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Synopsis: Large-scale patterns of land use and fragmentation have been associated with the decline of many imperiled wildlife populations. Lesser prairie-chickens (Tympanuchus pallidicinctus) are restricted to the southern Great Plains of North America, and their population and range have declined by > 90% over the past 100 years. Our objective was to examine scale-dependent relationships between landscape structure and change and long-term population trends for lesser prairie-chicken populations in the southern Great Plains. We used a geographic information system (GIS) to quantify landscape composition, pattern and change at multiple scales (extents) for fragmented agricultural landscapes surrounding 10 lesser...
    map background search result map search result map Area requirements of grassland birds: a regional perspective. Road traffic and nearby grassland bird patterns in a suburbanizing landscape. Grassland Birds Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review. Multi-scale effects of habitat loss and fragmentation on lesser prairie-chicken populations in the US souther Great Plains. Magnitude of Habitat Fragmentation by Terrestrial Ecoregion BLM REA NGB 2011 Habitat Size Assessment for Bighorn Sheep Habitat BLM REA NGB 2011 Patch Habitat Score for Modeled Pronghorn Habitat BLM REA NGB 2011 Habitat Patch Assessment for Modeled Mule Deer Winter and Year Long Habitat BLM REA NGB 2011 Habitat Patch Assessment for Modeled Mule Deer Summer and Year Long Habitat Road traffic and nearby grassland bird patterns in a suburbanizing landscape. Multi-scale effects of habitat loss and fragmentation on lesser prairie-chicken populations in the US souther Great Plains. BLM REA NGB 2011 Habitat Size Assessment for Bighorn Sheep Habitat BLM REA NGB 2011 Patch Habitat Score for Modeled Pronghorn Habitat BLM REA NGB 2011 Habitat Patch Assessment for Modeled Mule Deer Winter and Year Long Habitat BLM REA NGB 2011 Habitat Patch Assessment for Modeled Mule Deer Summer and Year Long Habitat Area requirements of grassland birds: a regional perspective. Grassland Birds Magnitude of Habitat Fragmentation by Terrestrial Ecoregion Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review.