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USGS - science for a changing world

Thomas McMahon

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The project will utilize a 4.5 million acre study area on the Montana Glaciated Plains. The objectives are to (1) identify environmental conditions and management practices that will maintain habitat for grassland birds but not impact ranching sustainability, and (2) identify areas on the landscape that have the greatest conservation potential for grassland birds. This spatial analysis will provide the framework for a rigorous assessment of management actions on the Montana Glaciated Plains.
Land transformations occurring from energy development and agrarian use have altered the natural connectivity of fish communities inhabiting prairie waterways. The nation’s prairie waterways are obstructed by thousands of barriers that include road culverts, irrigation diversions, and dams. Connectivity is essential for the long term viability of aquatic species. One of the most promising adaptive management strategies for addressing impacts to aquatic systems by climate change and other landscape stressors is increasing connectivity. The purpose of this research is to characterize swimming abilities of three northern plains fish species; the sauger, the longnose dace, and the fathead minnow. The results of the...
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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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The Matador Ranch Grassbank is the most successful grassbank in the country, annually incentivizing conservation actions on over 200,000 acres of participating ranches. Incentives for management actions are in the form of discounts, which reduce the cost of leased grazing at the Matador Ranch. One of the required discounts for participating in the grassbank is a ranch management plan that guides grazing and benefits natural communities and the wildlife dependent upon them. This report details the results of our work to assess resource conditions and craft management plans with eight ranches on over 113,000 acres. Our analysis found that overall ranches implemented grazing management practices that maintained ecological...
Migration barriers and resulting habitat fragmentation are a major conservationconcern for freshwater fishes. Characterizing the swimming abilities of fish is vital forfishway design and identifying potential movement barriers. The objective of this studywas to assess the swimming performance of two of the most widely distributed prairiefishes, the large-bodied, large river sauger Sander Canadensis, and the small-bodied,small stream longnose dace Rhinichthys cataractae. Swimming performance for bothspecies was assessed using a variety of metrics (passage success, maximum ascentdistance, maximum sprint speed) in an open channel flume over a range of velocities(sauger, 51, 80, 93 cm/; dace, 39, 64, 78, and 90 cm/s),...
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