Panmixia and Limited Interspecific Introgression in Coyotes (Canis latrans) from West Virginia and Virginia, USA.

The expansion of coyotes (Canis latrans) into the eastern United States has had major consequences for ecological communities and wildlife managers. Despite this, there has been little investigation of the genetics of coyotes across much of this region, especially outside of the northeast. Understanding patterns of genetic structure and interspecific introgression would provide insights into the colonization history of the species, its response to the modern environment, and interactions with other canids. We examined the genetic characteristics of 121 coyotes from the mid-Atlantic states of West Virginia and Virginia by genotyping 17 polymorphic nuclear DNA microsatellite loci. These genotypes were compared with those from other canid populations to evaluate the extent of genetic introgression. We conducted spatial clustering analyses and spatial autocorrelation to assess genetic structure among sampled coyotes. Coyotes across the 2 states had high genetic diversity, and we found no evidence of genetic structure. Six to sixteen percent of individuals displayed some evidence of genetic introgression from other species depending on the method and criteria used, but the population possessed predominantly coyote ancestry. Our findings suggested introgression from other canid populations has played less of a role in shaping the genetic character of coyotes in these states compared with populations closer to the Canadian border. Coyotes appear to display a panmictic population structure despite high habitat heterogeneity and heavy human influence in the spatial environment, underscoring the adaptability of the species.

Epizootiology of an epizootic hemorrhagic disease outbreak in West Virginia.

An outbreak of epizootic hemorrhagic disease virus, serotype 2 (EHDV-2) was responsible for localized white-tailed deer (Odocoileus virginianus) mortality in Hardy and Hampshire counties, West Virginia (USA), in the summer and fall of 1993. Using available historical data on regional herd immunity, data opportunistically collected during the epizootic, and postepizootic sampling of hunter-harvested deer, we grossly estimate certain epidemiologic parameters and compare findings to a hypothesis about hemorrhagic disease outbreaks in the Appalachian Mountains. During the epizootic, 57.9 km(2) were actively searched and 228 dead deer were found. Epizootic hemorrhagic disease virus, serotype 2 was isolated from seven of nine deer sampled in Hardy and Hampshire counties. Preepizootic exposure of deer to EHD viruses was unknown, but available data suggest that it was negligible. The geographic distribution of the outbreak was defined by plotting the locations of dead deer found during the outbreak, as well as the locations of deer harvested by hunters after the outbreak that had antibodies to EHDV-2 on a map sectioned into 16.65 km(2) rectangular sections. Sections that included one or more dead deer or hunter-harvested deer with antibodies to EHDV-2 were included in the defined outbreak area. Postoutbreak sampling revealed monospecific EHDV-2 antibodies in 12% of deer harvested by hunters within the defined outbreak area. Based on the available data and accepting certain assumptions, gross calculations suggest that this outbreak appears to have been isolated and probably killed a high percentage of the deer that were infected. This is consistent with the hypothesis that sporadic hemorrhagic disease outbreaks in the Appalachian Mountains are usually localized and severe.