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David E. Naugle

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Genetic networks can characterize complex genetic relationships among groups of individuals, which can be used to rank nodes most important to the overall connectivity of the system. Ranking allows scarce resources to be guided towards nodes integral to connectivity. The greater sage-grouse (Centrocercus urophasianus) is a species of conservation concern that breeds on spatially discrete leks that must remain connected by genetic exchange for population persistence. We genotyped 5,950 individuals, from 1,200 greater sage-grouse leks distributed across the entire species’ geographic range. We found a small world network composed of 458 nodes connected by 14,481 edges that are described here. The files associated...
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Rapid expansion of cropland threatens grassland ecosystems across western North America and broad-scaleplanning can be a catalyst motivating individuals and agencies to accelerate conservation. Sprague’s Pipit(Anthus spragueii) is an imperiled grassland songbird whose population has been declining rapidly in recent decades.Here, we present a strategic framework for conservation of pipits and their habitat in the northern GreatPlains.We modeled pipit distribution across its million-km2 breeding range in Canada and the U.S.We describefactors shaping distribution, delineate population cores and assess vulnerability to future grassland losses. Pipitsselected landscapes with a high proportion of continuous grassland...
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Functional connectivity, quantified using landscape genetics, can inform conservation through the identification of factors linking genetic structure to landscape mechanisms. We used breeding habitat metrics, landscape attributes, and indices of grouse abundance, to compare fit between structural connectivity and genetic differentiation within five long-established Sage-Grouse Management Zones (MZ) I–V using microsatellite genotypes from 6,009 greater sage-grouse (Centrocercus urophasianus) collected across their range. We estimated structural connectivity using a circuit theory-based approach where we built resistance surfaces using thresholds dividing the landscape into “habitat” and “nonhabitat” and nodes were...
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Temperate grassland ecosystems are imperiled globally, and habitat loss in North America has resulted in steepdeclines of endemic songbirds. Commercial livestock grazing is the primary land use in rangelands that supportremaining bird populations. Some conservationists suggest using livestock as “ecosystem engineers” to increasehabitat heterogeneity in rangelands because birds require a spectrum of sparse to dense vegetation cover.However, grazing effects remain poorly understood because local studies have not incorporated broad-scaleenvironmental constraints on herbaceous growth. We surveyed grassland birds across a region spanning26 500 km2 in northeast Montana, United States to assess how distribution and abundance...
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