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Stream fragmentation alters the structure of aquatic communities on a global scale, generally through loss of native species. Among riverscapes in the Great Plains of North America, stream fragmentation and hydrologic alteration (flow regulation and dewatering) are implicated in the decline of native fish diversity. This study documents the spatio–temporal distribution of fish reproductive guilds in the fragmented Arkansas and Ninnescah rivers of south-central Kansas using retrospective analyses involving 63 years of fish community data. Pelagic-spawning fishes declined throughout the study area during 1950–2013, including Arkansas River shiner (Notropis girardi) last reported in 1983, plains minnow (Hybognathus...
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: CATFISHES/MINNOWS, Colorado, Colorado, FISH, Federal resource managers, All tags...
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Genetic, demographic, and environmental processes affect natural populations synergistically, and understanding their interplay is crucial for the conservation of biodiversity. Stream fishes in metapopulations are particularly sensitive to habitat fragmentation because persistence depends on dispersal and colonization of new habitat but dispersal is constrained to stream networks. Great Plains streams are increasingly fragmented by water diversion and climate change, threatening connectivity of fish populations in this ecosystem. We used seven microsatellite loci to describe population and landscape genetic patterns across 614 individuals from 12 remaining populations of Arkansas darter ( Etheostoma cragini) in...
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Within grassland communities of the GPLCC one such key indicator species is the Lesser Prairie-chicken (Tympanuchus pallidinctus). Lesser Prairie-chicken range extends across the southern portion of the GPLCC area throughout Texas, Oklahoma, New Mexico, and Kansas. Lesser Prairie-chickens are a good target species because they are widely distributed across the southern GPLCC, are a species of conservation concern, have large home ranges, and are likely sensitive to anthropogenic disturbances. Similarly, the Greater Prairie-chicken (Tympanuchus cupido), is a species of conservation concern, with large home range, distributed across the northern portion of the GPLCC including portions of Oklahoma, Kansas, Nebraska,...
Little is known about the population biology of midget faded rattlesnakes, a sensitive subspecies of the Western Rattlesnake, despite conservation efforts to protect them. We conducted a molecular genetic study of midget faded rattlesnakes in southwestern Wyoming to investigate population genetic structure in this area, particularly with reference to Flaming Gorge Reservoir and its associated human activities, and to document levels of genetic diversity. We genotyped 229 snakes from 11 sampling sites using 9 microsatellite loci. We found significant levels of genetic structure among sites that were better explained by geographic region and isolation by distance than by position relative to waterways. Sites on either...
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This data set contains genetic information collected from eelgrass (Zostera marina) populations along the Pacific coast of North America from Alaska to Baha California. A total of 447 samples were collected comprising 401 unique individuals (genets) and 46 clones (ramets) from which 10 microsatellite DNA loci were obtained.
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Biodiversity in stream networks is threatened globally by interactions between habitat fragmentation and altered hydrologic regimes. In the Great Plains of North America, stream networks are fragmented by 19,000 anthropogenic barriers, and flow regimes are altered by surface water retention and groundwater extraction. We documented the distribution of anthropogenic barriers and dry stream segments in five basins covering the central Great Plains to assess effects of broad-scale environmental change on stream fish community structure and distribution of reproductive guilds. We used an information-theoretic approach to rank competing models in which fragmentation, discharge magnitude, and percentage of time streams had...
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: CATFISHES/MINNOWS, Colorado, Colorado, FISH, Federal resource managers, All tags...
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Genetic, demographic, and environmental processes affect natural populations synergistically, and understanding their interplay is crucial for the conservation of biodiversity. Stream fishes in metapopulations are particularly sensitive to habitat fragmentation because persistence depends on dispersal and colonization of new habitat but dispersal is constrained to stream networks. Great Plains streams are increasingly fragmented by water diversion and climate change, threatening connectivity of fish populations in this ecosystem. We used seven microsatellite loci to describe population and landscape genetic patterns across 614 individuals from 12 remaining populations of Arkansas darter ( Etheostoma cragini) in...
The distribution and abundance of the greater sage-grouse (Centrocercus urophasianus) have declined dramatically, and as a result the species has become the focus of conservation efforts. We conducted a range-wide genetic survey of the species which included 46 populations and over 1000 individuals using both mitochondrial sequence data and data from seven nuclear microsatellites. Nested clade and STRUCTURE analyses revealed that, in general, the greater sage-grouse populations follow an isolation-by-distance model of restricted gene flow. This suggests that movements of the greater sage-grouse are typically among neighbouring populations and not across the species, range. This may have important implications if...
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Biodiversity in stream networks is threatened globally by interactions between habitat fragmentation and altered hydrologic regimes. In the Great Plains of North America, stream networks are fragmented by 19,000 anthropogenic barriers, and flow regimes are altered by surface water retention and groundwater extraction. We documented the distribution of anthropogenic barriers and dry stream segments in five basins covering the central Great Plains to assess effects of broad-scale environmental change on stream fish community structure and distribution of reproductive guilds. We used an information theoretic approach to rank competing models in which fragmentation, discharge magnitude, and percentage of time streams...
Categories: Data, Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2012, CATFISHES/MINNOWS, CO-01, CO-02, CO-03, All tags...
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Genetic, demographic, and environmental processes affect natural populations synergistically, and understanding their interplay is crucial for the conservation of biodiversity. Stream fishes in metapopulations are particularly sensitive to habitat fragmentation because persistence depends on dispersal and colonization of new habitat but dispersal is constrained to stream networks. Great Plains streams are increasingly fragmented by water diversion and climate change, threatening connectivity of fish populations in this ecosystem. We used seven microsatellite loci to describe population and landscape genetic patterns across 614 individuals from 12 remaining populations of Arkansas darter ( Etheostoma cragini) in...
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...
The rapid expansion of road networks has reduced connectivity among populations of flora and fauna. The resulting isolation is assumed to increase population extinction rates, in part because of the loss of genetic diversity. However, there are few cases where loss of genetic diversity has been linked directly to roads or other barriers. We analysed the effects of such barriers on connectivity and genetic diversity of 27 populations of Ovis canadensis nelsoni (desert bighorn sheep). We used partial Mantel tests, multiple linear regression and coalescent simulations to infer changes in gene flow and diversity of nuclear and mitochondrial DNA markers. Our findings link a rapid reduction in genetic diversity (up to...
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Adult movement and natal dispersal data demonstrate that Northern Goshawks (Accipiter gentilis) are able to travel over long distances, suggesting a large functional population. However, these data are unable to determine whether these movements contribute to gene flow among adjacent breeding areas. We used eight microsatellite DNA loci and mitochondrial DNA control-region sequence data to assess population structure of Northern Goshawks breeding in Utah. Goshawks had moderate levels of genetic variation at microsatellite loci (observed heterozygosity = 50%), similar to levels found in other medium-sized, highly mobile birds. Overall estimates of interpopulation variance in microsatellite alleles (FST = 0.011) and...
Mitochondrial DNA control region sequences of spotted owls (Strix occidentalis) allowed us to investigate gene flow, genetic structure, and biogeographic relationships among these forest-dwelling birds of western North America. Estimates of gene flow based on genetic partitioning and the phylogeography of haplotypes indicate substantial dispersal within three long-recognized subspecies. However, patterns of individual phyletic relationships indicate a historical absence of gene flow among the subspecies, which are essentially monophyletic. The pattern of haplotype coalescence enabled us to identify the approximate timing and direction of a recent episode of gene flow from the Sierra Nevada to the northern coastal...
In the Sonoran Desert of North America, populations of the desert tortoise (Gopherus agassizii) occur in rocky foothills throughout southwestern Arizona and northwestern Mexico. Although tortoise populations appear to be isolated from each other by low desert valleys, individuals occasionally move long distances between populations. Increasingly, these movements are hindered by habitat fragmentation due to anthropogenic landscape changes. We used molecular techniques and radiotelemetry to examine movement patterns of desert tortoises in southern Arizona. We collected blood samples from 170 individuals in nine mountain ranges and analyzed variability in seven microsatellite loci to determine genetic differentiation...
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Conclusions: Grizzly bear population fragmentation corresponded to the presence of settled mountain valleys and major highways. In these disturbed areas, the inter-area movements of female bears was affected more than for male bears. Without female connectivity, small subpopulations of grizzly bears are not viable over the long term. Thresholds/Learnings: Females grizzlies reduced their movement rates drastically when settlement increased to >20% of a given area. In highly settled areas (>50% settlement), both sexes demonstrated similar reductions in movement. Synopsis: Researchers studied the current state and potential causes of population fragmentation in grizzly bears over western Canada, the Greater Yellowstone...
Categories: Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: Alberta, British Columbia, Canadian Rockies, Chilcotin Ranges and Fraser Plateau, Clear Hills and Western Alberta Upland, All tags...
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We used comparative landscape genetics to examine the relative roles of historical events, intrinsic traits and landscape factors in determining the distribution of genetic diversity of river fishes across the North American Great Plains. Spatial patterns of diversity were overlaid on a patch-based graphical model and then compared within and among three species that co-occurred across five Great Plains watersheds. Species differing in reproductive strategy (benthic vs. pelagic-spawning) were hypothesized to have different patterns of genetic diversity, but the overriding factor shaping contemporary patterns of diversity was the signature of past climates and geological history. Allelic diversity was significantly...
Categories: Data, Publication; Types: Citation, Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: CATFISHES/MINNOWS, Colorado, Colorado, FISH, Federal resource managers, All tags...
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The black‐tailed prairie dog (Cynomys ludovicianus) is considered an indicator species for the short grass prairie of North America; however, this species currently occupies an estimated 2% of its original distribution. Persistent and pervasive poisoning, and sylvatic plague have fragmented the remaining populations. It is not well understood how these population fragments are connected in a heterogeneous landscape of land use practices and land cover types, but quantifying population isolation and individual measures of dispersal across the landscape are essential to predicting both the vulnerability of extinction due to stochastic processes and the probability of disease emergence. To better understand how land...
Categories: Data, Project; Types: Map Service, OGC WFS Layer, OGC WMS Layer, OGC WMS Service; Tags: 2011, BTPD, BTPD, Black-tailed Prairie Dog (Cynomys ludovicianus), Black-tailed Prairie Dog (Cynomys ludovicianus), All tags...
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On a global scale biodiversity within river networks is threatened by interactions between habitat fragmentation and altered hydrologic regimes. In the Great Plains of North America, stream networks are fragmented by >19,000 anthropogenic barriers and flow regimes are altered by surface water retention and groundwater extraction. We documented the distribution of anthropogenic barriers and dry stream segments in five basins covering the central Great Plains to assess effects of broad-scale environmental change on stream fish community structure, distribution of reproductive guilds, and genetic integrity of select populations. We used an information-theoretic approach to rank competing models involving fragmentation,...
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Habitat fragmentation and degradation impacts an organism's ability to navigate the landscape, ultimately resulting in decreased gene flow and increased extinction risk. Understanding how landscape composition impacts gene flow (i.e., connectivity) and interacts with scale is essential to conservation decision-making. We used a landscape genetics approach implementing a recently developed statistical model based on the generalized Wishart probability distribution to identify the primary landscape features affecting gene flow and estimate the degree to which each component influences connectivity for Gunnison sage-grouse (Centrocercus minimus). We were interested in two spatial scales: among distinct populations...


map background search result map search result map Gene flow and genetic characterization of Northern goshawks breeding in Utah Conservation status, genetics, and population vulnerability of Arkansas darter (Etheostoma cragini) in Colorado Patterns and Processes of Dispersal of Black-Tailed Prairie Dogs in a Heavily Managed Landscape of the Great Plains Landscape Conservation Cooperative Population fragmentation and inter-ecosystem movements of grizzly bears in western Canada and the northern United States. Conservation Priorities for Great Plains Fish Communities Based on Riverscape Connectivity and Genetic Integrity of Populations Analysis Data: Conservation status, genetics, and population vulnerability of Arkansas darter (Etheostoma cragini) in Colorado Final Report: Development of regional planning tools to assess the impacts of climate and land use change on a sensitive grassland bird Final Report: Conservation Priorities for Great Plains Fish Communities Based on Riverscape Connectivity and Genetic Integrity of Populations Eelgrass (Zostera marina) Microsatellite DNA Data; Pacific Coast of North America, 2000-2009 Publication: Fragmentation and dewatering transform Great Plains stream fish communities Publication: Fragmentation and drying ratchet down Great Plains stream fish diversity Publication: Comparative riverscape genetics reveals reservoirs of genetic diversity for conservation and restoration of Great Plains fishes Publication: Water availability strongly impacts population genetic patterns of an imperiled Great Plains endemic fish Gunnison sage-grouse predicted gene flow (conductance) surfaces, Colorado, United States Gunnison sage-grouse predicted gene flow (conductance) surfaces, Colorado, United States Conservation status, genetics, and population vulnerability of Arkansas darter (Etheostoma cragini) in Colorado Publication: Water availability strongly impacts population genetic patterns of an imperiled Great Plains endemic fish Analysis Data: Conservation status, genetics, and population vulnerability of Arkansas darter (Etheostoma cragini) in Colorado Gene flow and genetic characterization of Northern goshawks breeding in Utah Patterns and Processes of Dispersal of Black-Tailed Prairie Dogs in a Heavily Managed Landscape of the Great Plains Landscape Conservation Cooperative Conservation Priorities for Great Plains Fish Communities Based on Riverscape Connectivity and Genetic Integrity of Populations Final Report: Development of regional planning tools to assess the impacts of climate and land use change on a sensitive grassland bird Final Report: Conservation Priorities for Great Plains Fish Communities Based on Riverscape Connectivity and Genetic Integrity of Populations Publication: Fragmentation and dewatering transform Great Plains stream fish communities Publication: Fragmentation and drying ratchet down Great Plains stream fish diversity Publication: Comparative riverscape genetics reveals reservoirs of genetic diversity for conservation and restoration of Great Plains fishes Population fragmentation and inter-ecosystem movements of grizzly bears in western Canada and the northern United States. Eelgrass (Zostera marina) Microsatellite DNA Data; Pacific Coast of North America, 2000-2009