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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...
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...
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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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This map layer is extracted from a grid map of North America including the Caribbean and most of Mexico. The map layer is an excerpt from a global assessment of forest fragmentation (Riitters et al., 2000). Each pixel value represents an index of forest fragmentation for the surrounding 81 sq. km. The map layer was created by applying spatial algorithms to a 1 sq. km. resolution map of global land cover (Loveland and Belward 1997) known as NAIGBP1_2L, obtained from the USGS Center for EROS Distributed Active Archive Center (DAAC) as part of the Global Land Cover Characteristics database (GLCC)(Loveland et al. 1991, 1999). One of six categories of fragmentation was identified for each forested pixel in North...
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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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Habitat fragmentation is considered to be a leading cause that is responsible for the long-term population declines of Northern Bobwhites. There are numerous factors responsible for habitat fragmentation such as expanding suburbanization, intensification of agricultural and forestry practices, and invasions of exotic plants; the unifying theme is how people use land for settlement and the production of food and fiber. As patches of habitat become smaller and more isolated, populations experience a lower probability of persistence that results in local extinctions, which can lead to larger, and perhaps even regional extinctions. However, we lack a strong empirical and quantified basis that describes the numerical...
Categories: Data, Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2015, 2016, Academics & scientific researchers, Conservation Design, Conservation NGOs, All tags...
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Fragmentation and loss of natural habitat have important consequences for wild populations and can negatively affect long-term viability and resilience to environmental change. Salt marsh obligate species, such as those that occupy the San Francisco Bay Estuary in western North America, occupy already impaired habitats as result of human development and modifications and are highly susceptible to increased habitat loss and fragmentation due to global climate change. We examined the genetic variation of the California Ridgway’s rail ( Rallus obsoletus obsoletus), a state and federally endangered species that occurs within the fragmented salt marsh of the San Francisco Bay Estuary. We genotyped 107 rails across 11...
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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...
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...


map background search result map search result map 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 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. Forest Fragmentation Risk, Contiguous US Impacts of Habitat Fragmentation on Northern Bobwhites in the Gulf Coast Prairie Landscape Conservation Cooperative A Century of Landscape Disturbance and Urbanization of the San Francisco Bay Region affects the Present-day Genetic Diversity of the California Ridgway’s Rail (Rallus obsoletus obsoletus) 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 Impacts of Habitat Fragmentation on Northern Bobwhites in the Gulf Coast Prairie Landscape Conservation Cooperative Grassland Birds Mitigating swine odor with strategically designed shelterbelt systems: a review. Forest Fragmentation Risk, Contiguous US