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In the absence of obvious barriers to dispersal microsatellite studies of vagile mammalian carnivores frequently find panmictic-like genetic structure over wide scales, whereas high levels of differentiation at much finer scales are detected with mitochondrial DNA (mtDNA). Given the maternal inheritance of mtDNA, these differences are often attributed to male-biased dispersal, remnants of postglacial range expansion, or both. Based on such contrasting results, it is not always clear how to delineate contemporary populations. We investigated the genetic structure of American black bears (Ursus americanus) over a wide geographic area (>1,700 km) that has no obvious physiogeographic barriers to gene flow. We analyzed a 315-base pair fragment of the mtDNA control region from 660 individual bears from 23 regions of Ontario, Canada. Relative to black bear studies based on nuclear data, mitochondrial analyses revealed much stronger patterns of genetic structure among regions (0.09 < FST < 0.44), even at small-scale intervals (<150 km), which likely reflects strong female philopatry combined with male-biased dispersal. The patterns of genetic differentiation among regions were consistent with previously described historical patterns in black bears, specifically the division of the species into 2 phylogeographic clades (coastal and continental). We confirmed that further subdivision of the continental clade occurs in a region where obvious physiogeographic barriers do not exist. We postulate that this small-scale differentiation can be explained by residual patterns from postglacial recolonization routes on either side of the Great Lakes. We suggest that it was maintained through extreme female philopatry due to habitat saturation following the postglacial geographic expansion. Based on our results, we propose that a combination of several molecular markers can be more useful in defining population units for conservation and management decisions than biparentally inherited microsatellites. [ABSTRACT FROM AUTHOR]

Interpretation of the genetic composition and taxonomic history of wolves in the western Great Lakes region (WGLR) of the United States has long been debated and has become more important to their conservation given the recent changes in their status under the Endangered Species Act. Currently, the two competing hypotheses on WGLR wolves are that they resulted from hybridization between (i) grey wolves ( Canis lupus) and western coyotes ( C. latrans) or (ii) between grey wolves and eastern wolves ( C. lycaon). We performed a genetic analysis of sympatric wolves and coyotes from the region to assess the degree of reproductive isolation between them and to clarify the taxonomic status of WGLR wolves. Based on data from maternal, paternal and bi-parental genetic markers, we demonstrate a clear genetic distinction between sympatric wolves and coyotes and conclude that they are reproductively isolated and that wolf-coyote hybridization in the WGLR is uncommon. The data reject the hypothesis that wolves in the WGLR derive from hybridization between grey wolves and western coyotes, and we conclude that the extant WGLR wolf population is derived from hybridization between grey wolves and eastern wolves. Grey-eastern wolf hybrids ( C. lupus × lycaon) comprise a substantial population that extends across Michigan, Wisconsin, Minnesota and western Ontario. These findings have important implications for the conservation and management of wolves in North America, specifically concerning the overestimation of grey wolf numbers in the United States and the need to address policies for hybrids. [ABSTRACT FROM AUTHOR]

We have isolated and characterized 17 tetranucleotide microsatellite loci for Blanchard's cricket frog ( Acris crepitans blanchardi), an anuran common in the central USA. Sixteen loci were organized into four multiplex amplification reactions. These loci were highly polymorphic when screened in 55 individuals from two distant populations, with 11–48 alleles per locus (average = 24.8). Observed and expected heterozygosities ranged from 0.18 to 0.97 and from 0.17 to 0.96, respectively. Nine loci were also polymorphic in Acris crepitans crepitans, with seven polymorphic in Acris gryllus. Five loci amplified in all three taxa. These loci will be useful for population- and species-level investigations of this widespread group. [ABSTRACT FROM AUTHOR]

This study examined the genetic nature and relatedness of Canis latrans (Coyotes) in eastern Massachusetts (i.e., eastern Coyotes). We characterized 67 animals at the mitochondrial DNA control region, and 55 of those at 8 microsatellite loci. Structure analysis and factorial correspondence analysis of the microsatellite genotypes indicated that the eastern Coyotes in Massachusetts clustered with other northeastern Canis populations and away from western Coyotes, C. lycaon (Eastern Wolves), and C. lupus (Gray Wolves). They contained mitochondrial haplotypes from both western Coyotes and Eastern Wolves, consistent with their hybrid origin from these two species. There was no evidence of either C. lupus familiaris (Domestic Dog) or Gray Wolf mitochondrial DNA in the animals. These results indicate that the eastern Coyote should more appropriately be termed "Coywolf" to reflect their hybrid (C. latrans x lycaon) origin. Genetic data were also used to assess parental and kinship relationships, and confirmed that family units typically contain an unrelated breeding pair and their offspring. Lastly, a synthesis of knowledge of the eastern Coyote as well as implications for Wolf recovery in the northeast US is provided. [ABSTRACT FROM AUTHOR]

Sampling of feces for genetic studies of wild populations can be problematic because of the low quality and quantity of template DNA obtained. We used cotton swabs in the field to isolate the mucous layer on the surface of fresh wolf (Canis lupus, C. lycaon, and their hybrids) scats followed by immediate preservation, and compared microsatellite genotyping of DNA from these fresh field swabs (FS) to that of previously frozen laboratory swabs (LS). In single polymerase chain reactions (PCRs) of 2 multiplexes, amplification at 8 loci was higher in the FS samples (FS = 50%, LS = 15%; P 5 0.02) because proportion, quantity, and quality of large fragment wolf nuclear DNA from these samples was greater (2.5-25%, 6.25-62.5 ng/swab, 35% amplified at 1,000 base pairs [bp]) than from the LS samples (1.9%-10%, 4.7-25 ng/ swab, 10% amplified at 1,000 bp). Paired blood and fresh field-swabbed samples had identical genotypes. In 84 multiplex PCRs we found no evidence of allelic dropout associated with low template quality or quantity. We conclude that field swabbing of fresh wolf scat facilitates field storage and reduces the need for multiple amplifications at single microsatellite loci, thereby reducing the genotyping costs for wildlife projects that use noninvasive samples. [ABSTRACT FROM AUTHOR]