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We capitalized on a regional-scale, anthropogenic experiment?the reduction of black-tailed prairie dog (Cynomys ludovicianus) towns across the Great Plains of North America?to test the hypothesis that decline of this species has led to declines in diversity of native grassland vertebrates of this region. We compared species richness and species composition of non-volant mammals, reptiles and amphibians at 36 prairie dog towns and 36 paired sites in the Panhandle Region of Oklahoma during the summers and falls of 1997, 1998 and 1999. We detected 30 species of mammals, 18 species of reptiles and seven species of amphibians. Comparisons between communities at prairie dog towns and paired sites in the adjacent landscape...
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...
Climate changes impose requirements for many species to shift their ranges to remain within environmentally tolerable areas, but near-continuous regions of intense human land use stretching across continental extents diminish dispersal prospects for many species. We reviewed the impact of habitat loss and fragmentation on species? abilities to track changing climates and existing plans to facilitate species dispersal in response to climate change through regions of intensive land uses, drawing on examples from North America and elsewhere. We identified an emerging analytical framework that accounts for variation in species' dispersal capacities relative to both the pace of climate change and habitat availability....
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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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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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Synopsis: Recent reports clearly indicate that odor emitted from concentrated livestock production facilities in the Midwest of the US is a significant social problem that negatively impacts rural and state economies, human health, and the quality of rural life. A potential incremental approach to dealing with livestock odor is the use of shelterbelts arranged in strategic designs near and within livestock facilities. This review outlines the various ways that shelterbelts can be effective technology which biophysically mitigates odor thereby reducing social conflict from odor nuisance. The biophysical potential of shelterbelts to mitigate livestock odor arises from the tree/shrub impacts on the central characteristics...
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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...
Abstract (from http://www.sciencedirect.com/science/article/pii/S1470160X15005518): Although localized effects of individual dams on stream fish assemblages have been relatively well-studied, less is known about the effects of multiple dams within a stream network on fishes and the patterns that emerge when the combined effects of individual and multiple dams are viewed across entire river basins, ecoregions, and states. This study evaluated multiple stream network fragmentation metrics representing localized (e.g., distance-to-dams) and cumulative (e.g., total upstream reservoir storage) dam influences on streams in Michigan, Wisconsin, and Minnesota, developing an approach for identifying suitable fish indicators...
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Synopsis: Researchers measured the effects of grassland amount and fragmentation on upland and wetland songbird and duck densities and nest success across 16 landscapes in southern Alberta. By comparing these landscape-level effects with local-scale responses, including distance to various edges and vegetation characteristics, the study demonstrated that 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. Landscape level effects were much less apparent when local characteristics were included in the models. Therefore, researchers concluded that local habitat...
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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...
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...
Landscape connectivity is critical to species persistence in the face of habitat loss and fragmentation. Graph theory is a well-defined method for quantifying connectivity that has tremendous potential for ecology, but its application has been limited to a small number of conservation scenarios, each with a fixed proportion of habitat. Because it is important to distinguish changes in habitat configuration from changes in habitat area in assessing the potential impacts of fragmentation, we investigated two metrics that measure these different influences on connectivity. The first metric, graph diameter, has been advocated as a useful measure of habitat configuration. We propose a second area-based metric that combines...
Conclusions:Forest clearcutting differentialy affects birds of different ages. There is a threshold distance between reserves below which birds do not mind crossing clear cuts, making corridors more important as clearcut area and distance between forest reserves expandsThresholds/Learnings:
Conclusions:Results indicated that system and species-specific considerations are important when assessing the potential outcome of habitat loss and fragmentation on regional biotaThresholds/Learnings:
Climate changes impose requirements for many species to shift their ranges to remain within environmentally tolerable areas, but near-continuous regions of intense human land use stretching across continental extents diminish dispersal prospects for many species. We reviewed the impact of habitat loss and fragmentation on species? abilities to track changing climates and existing plans to facilitate species dispersal in response to climate change through regions of intensive land uses, drawing on examples from North America and elsewhere. We identified an emerging analytical framework that accounts for variation in species' dispersal capacities relative to both the pace of climate change and habitat availability....
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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: 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....
This cooperative effort by USDA Forest Service Research and the National Forest System assesses the state of knowledge related to the conservation status of four forest carnivores in the western United States: American marten, fisher, lynx, and wolverine. The conservation assessment reviews the biology and ecology of these species. It also discusses management considerations stemming from what is known and identifies information needed. Overall, we found huge knowledge gaps that make it difficult to evaluate the species' conservation status. In the western United States, the forest carnivores in this assessment are limited to boreal forest ecosystems. These forests are characterized by extensive landscapes with...
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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...
map background search result map search result map Area requirements of grassland birds: a regional perspective. 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 Grassland Birds 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. Ecological determinants of species loss in remnant prairies. Mitigating swine odor with strategically designed shelterbelt systems: a review. A multi-scale analysis of avian response to habitat amount and fragmentation in the Canadian dry mixed-grass prairie. Relationships among grizzly bears, highways, and habitat in Banff-Bow Valley, Alberta, Canada. A multi-scale analysis of avian response to habitat amount and fragmentation in the Canadian dry mixed-grass prairie. Minimum habitat requirements for establishing translocated cutthroat trout populations. Ecological determinants of species loss in remnant prairies. Factors influencing the dispersion and fragmentation of endangered mountain caribou populations Ecosystem Goods and Services Southern Alberta Assessment of Natural Asset Condition Area requirements of grassland birds: a regional perspective. Grassland Birds Mitigating swine odor with strategically designed shelterbelt systems: a review. Effects of habitat fragmentation on birds and mammals in landscapes with different proportions of suitable habitat: a review.