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The Arizona Toad (Anaxyrus microscaphus) is restricted to riverine corridors and adjacent uplands in the arid southwestern United States. As with numerous amphibians worldwide, populations are declining and face various known or suspected threats, from disease to habitat modification resulting from climate change. The Arizona Toad has been petitioned to be listed under the U.S. Endangered Species Act and was considered "warranted but precluded" citing the need for additional information – particularly regarding natural history (e.g., connectivity and dispersal ability). The objectives of this study were to characterize population structure and genetic diversity across the species' range. We used reduced-representation genomic sequencing to genotype 3,601 single nucleotide polymorphisms in 99 Arizona Toads from ten drainages across its range. Multiple analytical methods revealed two distinct genetic groups bisected by the Colorado River; one in the northwestern portion of the range in southwestern Utah and eastern Nevada and the other in the southeastern portion of the range in central and eastern Arizona and New Mexico. We also found subtle substructure within both groups, particularly in central Arizona where toads at lower elevations were less connected than those at higher elevations. The northern and southern parts of the Arizona Toad range are not well connected genetically and could be managed as separate units. Further, these data could be used to identify source populations for assisted migration or translocations to support small or potentially declining populations. [ABSTRACT FROM AUTHOR]

Interbasin water transfers are becoming an increasingly common tool to satisfy municipal and agricultural water demand, but their impacts on movement and gene flow of aquatic organisms are poorly understood. The Grand Ditch is an interbasin water transfer that diverts water from tributaries of the upper Colorado River on the west side of the Continental Divide to the upper Cache la Poudre River on the east side of the Continental Divide. We used single nucleotide polymorphisms to characterize population genetic structure in cutthroat trout (Oncorhynchus clarkii) and determine if fish utilize the Grand Ditch as a movement corridor. Samples were collected from two sites on the west side and three sites on the east side of the Continental Divide. We identified two or three genetic clusters, and relative migration rates and spatial distributions of admixed individuals indicated that the Grand Ditch facilitated bidirectional fish movement across the Continental Divide, a major biogeographic barrier. Previous studies have demonstrated ecological impacts of interbasin water transfers, but our study is one of the first to use genetics to understand how interbasin water transfers affect connectivity between previously isolated watersheds. We also discuss implications on native trout management and balancing water demand and biodiversity conservation. [ABSTRACT FROM AUTHOR]

The delineation of intraspecific units that are evolutionarily and demographically distinct is an important step in the development of species-specific management plans. Neutral genetic variation has served as the primary data source for delineating “evolutionarily significant units,” but with recent advances in genomic technology, we now have an unprecedented ability to utilize information about neutral and adaptive variation across the entire genome. Here, we use traditional genetic markers (microsatellites) and a newer reduced-representation genomic approach (single nucleotide polymorphisms) to delineate distinct groups of white-tailed ptarmigan (Lagopus leucura), an alpine-obligate species that is distributed in naturally fragmented habitats from Alaska to New Mexico. Five subspecies of white-tailed ptarmigan are currently recognized but their distinctiveness has not been verified with molecular data. Based on analyses of 436 samples at 12 microsatellite loci and 95 samples at 14,866 single nucleotide polymorphism loci, we provide strong support for treating two subspecies as distinct intraspecific units—L. l. altipetens, found in Colorado and neighboring states; and L. l. saxatilis, found on British Columbia’s Vancouver Island—but our findings reveal more moderate patterns of divergence within the remainder of the species’ range. Results based on genetic and genomic datasets generally agreed with one another, indicating that in many cases microsatellite loci may be sufficient for describing major patterns of genetic structure across species’ ranges. This work will inform future conservation and management decisions for the white-tailed ptarmigan, a species that may be vulnerable to future changes in climate. [ABSTRACT FROM AUTHOR]

The distribution of the Lesser Prairie-Chicken ( Tympanuchus pallidicinctus) has been markedly reduced due to loss and fragmentation of habitat. Portions of the historical range, however, have been recolonized and even expanded due to planting of conservation reserve program (CRP) fields that provide favorable vegetation structure for Lesser Prairie-Chickens. The source population(s) feeding the range expansion is unknown, yet has resulted in overlap between Lesser and Greater Prairie-Chickens ( T. cupido) increasing the potential for hybridization. Our objectives were to characterize connectivity and genetic diversity among populations, identify source population(s) of recent range expansion, and examine hybridization with the Greater Prairie-Chicken. We analyzed 640 samples from across the range using 13 microsatellites. We identified three to four populations corresponding largely to ecoregions. The Shinnery Oak Prairie and Sand Sagebrush Prairie represented genetically distinct populations ( F > 0.034 and F > 0.023 respectively). The Shortgrass/CRP Mosaic and Mixed Grass ecoregions appeared admixed ( F = 0.009). Genetic diversity was similar among ecoregions and N ranged from 142 (95 % CI 99-236) for the Shortgrass/CRP Mosaic to 296 (95 % CI 233-396) in the Mixed Grass Prairie. No recent migration was detected among ecoregions, except asymmetric dispersal from both the Mixed Grass Prairie and to a lesser extent the Sand Sagebrush Prairie north into adjacent Shortgrass/CRP Mosaic ( m = 0.207, 95 % CI 0.116-0.298, m = 0.097, 95 % CI 0.010-0.183, respectively). Indices investigating potential hybridization in the Shortgrass/CRP Mosaic revealed that six of the 13 individuals with hybrid phenotypes were significantly admixed suggesting hybridization. Continued monitoring of diversity within and among ecoregions is warranted as are actions promoting genetic connectivity and range expansion. [ABSTRACT FROM AUTHOR]

Gunnison Sage-grouse are an obligate sagebrush species that has experienced significant population declines and has been proposed for listing under the U.S. Endangered Species Act. In order to examine levels of connectivity among Gunnison Sage-grouse leks, we identified 13 novel microsatellite loci though next-generation shotgun sequencing, and tested them on the closely related Greater Sage-grouse. The number of alleles per locus ranged from 2 to 12. No loci were found to be linked, although 2 loci revealed significant departures from Hardy-Weinberg equilibrium or evidence of null alleles. While these microsatellites were designed for Gunnison Sage-grouse, they also work well for Greater Sage-grouse and could be used for numerous genetic questions including landscape and population genetics. [ABSTRACT FROM AUTHOR]

Greater sage-grouse ( Centrocercus urophasianus) within the Bi-State Management Zone (area along the border between Nevada and California) are geographically isolated on the southwestern edge of the species' range. Previous research demonstrated that this population is genetically unique, with a high proportion of unique mitochondrial DNA (mtDNA) haplotypes and with significant differences in microsatellite allele frequencies compared to populations across the species' range. As a result, this population was considered a distinct population segment (DPS) and was recently proposed for listing as threatened under the U.S. Endangered Species Act. A more comprehensive understanding of the boundaries of this genetically unique population (where the Bi-State population begins) and an examination of genetic structure within the Bi-State is needed to help guide effective management decisions. We collected DNA from eight sampling locales within the Bi-State ( N = 181) and compared those samples to previously collected DNA from the two most proximal populations outside of the Bi-State DPS, generating mtDNA sequence data and amplifying 15 nuclear microsatellites. Both mtDNA and microsatellite analyses support the idea that the Bi-State DPS represents a genetically unique population, which has likely been separated for thousands of years. Seven mtDNA haplotypes were found exclusively in the Bi-State population and represented 73 % of individuals, while three haplotypes were shared with neighboring populations. In the microsatellite analyses both STRUCTURE and FCA separate the Bi-State from the neighboring populations. We also found genetic structure within the Bi-State as both types of data revealed differences between the northern and southern part of the Bi-State and there was evidence of isolation-by-distance. STRUCTURE revealed three subpopulations within the Bi-State consisting of the northern Pine Nut Mountains (PNa), mid Bi-State, and White Mountains (WM) following a north-south gradient. This genetic subdivision within the Bi-State is likely the result of habitat loss and fragmentation that has been exacerbated by recent human activities and the encroachment of singleleaf pinyon ( Pinus monophylla) and juniper ( Juniperus spp.) trees. While genetic concerns may be only one of many priorities for the conservation and management of the Bi-State greater sage-grouse, we believe that they warrant attention along with other issues (e.g., quality of sagebrush habitat, preventing future loss of habitat). Management actions that promote genetic connectivity, especially with respect to WM and PNa, may be critical to the long-term viability of the Bi-State DPS. [ABSTRACT FROM AUTHOR]

Twenty-six polymorphic microsatellite markers were developed for the fox squirrel (Sciurus niger). The number of alleles ranged from 2 to 11 and observed heterozygosities ranged from 0.037 to 0.815. Preliminary screening revealed that numerous loci also were polymorphic in other squirrel species: Sciurus carolinensis and Tamiasciurus hudsonicus. These loci should be useful tools for investigating the social structure, mating tactics and movement behavior of fox squirrels. [ABSTRACT FROM AUTHOR]

The selection of an appropriate source population may be crucial to the long-term success of reintroduction programs. Appropriate source populations often are those that originate from the same genetic lineage as native populations. However, source populations also should exhibit high levels of genetic diversity to maximize their capacity to adapt to variable environmental conditions. Finally, it is preferable if source populations are genetically representative of historical lineages with little or no contamination from non-native or domesticated stocks. Here, we use nuclear (microsatellite) and cytoplasmic (mitochondrial control region) markers to assess the genetic suitability of a potential source population inhabiting the White River in Indiana: the last extant lake sturgeon population in the Ohio River drainage. The White River population exhibited slightly lower levels of genetic diversity than other lake sturgeon populations. However, the population's two private microsatellite alleles and three private haplotypes suggest a unique evolutionary trajectory. Population assignment tests revealed only two putative migrants in the White River, indicating the population has almost completely maintained its genetic integrity. Additionally, pairwise FST estimates indicated significant levels of genetic divergence between the White River and seven additional lake sturgeon populations, suggesting its genetic distinctiveness. These data indicate that the White River population may be the most suitable source population for future lake sturgeon reintroductions throughout the Ohio River drainage. Furthermore, the White River population appears to be a reservoir of unique genetic information and reintroduction may be a necessary strategy to ensure the persistence of this important genetic lineage. [ABSTRACT FROM AUTHOR]

The eastern gray squirrel ( Sciurus carolinensis) often serves as a model organism for investigations of wildlife ecology. The authors developed 11 polymorphic microsatellite markers to facilitate future research questions. The number of alleles per locus ranged from three to ten and observed heterozygosities ranged from 0.143 to 0.786. Interspecific screening revealed that several loci were polymorphic in Sciurus niger (eight loci) and Tamiasciurus hudsonicus (four loci). These markers will aid in investigations of movements, social structure and mating tactics of eastern gray squirrel populations. [ABSTRACT FROM AUTHOR]

Clark's nutcrackers are important seed dispersers for two widely-distributed western North American conifers, whitebark pine and limber pine, which are declining due to outbreaks of mountain pine beetle and white pine blister rust. Because nutcracker seed dispersal services are key to maintaining viable populations of these imperiled pines, knowledge of movement patterns of Clark's nutcrackers helps managers understand local extinction risks for these trees. To investigate population structure within Clark's nutcracker, we developed primers for and characterized 13 polymorphic microsatellite loci. In a screen of 22 individuals from one population, levels of variability ranged from 6 to 15 alleles. No loci were found to be linked, although 4 loci revealed significant departures from Hardy-Weinberg equilibrium and evidence of null alleles. These microsatellite loci will enable population genetic analyses of Clark's nutcrackers, which could provide insights into the spatial relationships between nutcrackers and the trees they help disperse. [ABSTRACT FROM AUTHOR]

Twenty one polymorphic microsatellite loci for the Japanese dace ( Tribolodon hakonensis) were isolated and characterized. The number of observed alleles per locus in 32 individuals ranged from 3 to 30. The observed and expected heterozygosities ranged from 0.125 to 0.969 and from 0.175 to 0.973, respectively. All loci conformed to Hardy-Weinberg equilibrium, no linkage disequilibrium was observed between pairs of loci and no loci showed evidence of null alleles. These microsatellite loci will be useful for investigating the intraspecific genetic variation and population structure of this species. [ABSTRACT FROM AUTHOR]

The Broad-tailed Hummingbird ( Selaphorus platycercus) breeds at higher elevations in the central and southern Rockies, eastern California, and Mexico and has been studied for 8 years in Rocky Mountain National Park, Colorado. Questions regarding the relatedness of Broad-tailed Hummingbirds banded together and then recaptured in close time proximity in later years led us to isolate and develop primers for 10 polymorphic microsatellite loci. In a screen of 25 individuals from a population in Rocky Mountain National Park, the 10 loci were found to have levels of variability ranging from two to 16 alleles. No loci were found to depart from linkage disequilibrium, although two loci revealed significant departures from Hardy-Weinberg equilibrium. These 10 microsatellite loci will be applicable for population genetic analyses, investigation of mating systems and relatedness, and may help gain insight into the migration timing and routes for this species. [ABSTRACT FROM AUTHOR]

Primers for 10 microsatellite loci were developed specifically to amplify low quantity and quality DNA in the endangered Indiana Bat ( Myotis sodalis). In a screen of 20 individuals from a population in Missouri, the 10 loci were found to have levels of variability ranging from seven to 18 alleles. No loci were found to be linked, although two loci revealed significant departures from Hardy-Weinberg equilibrium. These microsatellite loci will be applicable for population genetic analyses and for use in mark-recapture studies that utilize DNA collected non-invasively from fecal pellets, which will ultimately aid in management efforts. [ABSTRACT FROM AUTHOR]

In order to analyze population genetic structure at multiple spatial scales, 12 polymorphic microsatellite loci were developed for the eastern hellbender ( Cryptobranchus alleganiensis alleganiensis). The number of alleles per locus ranged from 6 to 12 (mean of 9.25 per locus) and the observed heterozygosity ranged from 0.645 to 0.935 among 31 individuals. Two loci exhibited significant deviations from Hardy-Weinberg equilibrium. No evidence for linkage disequilibrium was detected between pairs of loci. These markers will be used to examine population genetic structure across the geographic range of this declining species. [ABSTRACT FROM AUTHOR]

Twenty-five polymorphic microsatellite markers were developed for the endangered red-cockadedwoodpecker (Picoides borealis). The number of alleles ranged from two to five and observed heterozygosities ranged from 0.036 to 0.750. These loci should be useful tools for conducting research towards the management and conservation of this species. [ABSTRACT FROM AUTHOR]

We describe eight new polymorphic microsatellite loci (5 dinucleotide and three trinucleotide) for the eastern phoebe (Sayornis phoebe) to complement five previously published loci. The number of alleles per locus ranged from 3 to 15 and observed heterozygosities ranged from 0.33 to 0.91. Preliminary screening revealed that loci were polymorphic in other Tyrannidae: Empidonax virescens (n = 10), Tyrannus tyrannus (n = 10), Tyrannus vociferans (n = 5), and Tyrannus melancholicus (n = 28). [ABSTRACT FROM AUTHOR]

A correction to the article "Hierarchical spatial genetic structure in a distinct population segment of greater sage-grouse" that was published in the July 2014 issue, is presented.