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A key challenge in aquatic restoration efforts is documenting locations where ecological connectivity is disrupted in water bodies that are dammed or crossed by roads (road crossings). To prioritize actions aimed at restoring connectivity, we argue that there is a need for systematic inventories of these potential barriers at regional and national scales. Here, we address this limitation for the North American Great Lakes basin by compiling the best available spatial data on the locations of dams and road crossings. Our spatial database documents 38 times as many road crossings as dams in the Great Lakes basin, and case studies indicate that, on average, only 36% of road crossings in the area are fully passable...
Categories: Data,
Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2011,
2011,
2012,
2012,
2013,
Our goal was to predict road culvert passability, as defined by culvert outlet drop and outlet water velocity, for three fish swimming groups using remotely collected environmental variables that have been shown to influence the passability of road culverts.We generated four boosted regression tree models, one for road culvert outlet drop and one each for the three culvert outlet water velocities, and predicted the probability of impassable road culverts on low-order streams based on the models. Independent variables in the modelsincluded the upstream area draining to the culvert, slope at the culvert, stream segment gradient and stream reach gradient.Gradient of the stream segment was the most important predictor...
Categories: Data,
Publication;
Types: Citation,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
OGC WMS Service;
Tags: 2011,
2011,
2012,
2012,
2013,
Pacific trout Oncorhynchus spp. in western North America are strongly valued in ecological, socioeconomic, and cultural views, and have been the subject of substantial research and conservation efforts. Despite this, the understanding of their evolutionary histories, overall diversity, and challenges to their conservation is incomplete. We review the state of knowledge on these important issues, focusing on Pacific trout in the genus Oncorhynchus. Although most research on salmonid fishes emphasizes Pacific salmon, we focus on Pacific trout because they share a common evolutionary history, and many taxa in western North America have not been formally described, particularly in the southern extent of their ranges....
Understanding local and geographic factors influencing species distributions is a prerequisite for conservation planning. Our objective in this study was to model local and geographic variability in elevations occupied by native and nonnative trout in the northwestern Great Basin, USA. To this end, we analyzed a large existing data set of trout presence (5,156 observations) to evaluate two fundamental factors influencing occupied elevations: climate-related gradients in geography and local constraints imposed by topography. We applied quantile regression to model upstream and downstream distribution elevation limits for each trout species commonly found in the region (two native and two nonnative species). With...
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