Geology topics

Kenneth A. Logan

Publications and source records attributed to Kenneth A. Logan.

3 recordsLinked to original sources

USGS2023

Effects of hunting on mating, relatedness, and genetic diversity in a puma population

Hunting mortality can affect population abundance, demography, patterns of dispersal and philopatry, breeding, and genetic diversity. We investigated the effects of hunting on the reproduction and genetic diversity in a puma population in western Colorado, USA. We genotyped over 11,000 single nucleotide polymorphisms (SNPs), using double-digest, restriction site-associated DNA sequencing (ddRADseq) in 291 tissue samples collected as part of a study on the effects of hunting on puma population abundance and demography in Colorado from 2004 to 2014. The study was designed with a reference period (years 1–5), during which hunting was suspended, followed by a treatment period (years 6–10), in which hunting was reinstated. Our objectives were to examine the effects of hunting on: (1) paternity and male reproductive success; (2) the relatedness between pumas within the population, and (3) genetic diversity. We found that hunting reduced the average age of male breeders. The number of unique fathers siring litters increased each year without hunting and decreased each year during the hunting period. Mated pairs were generally unrelated during both time periods, and females were more closely related than males. Hunting was also associated with increased relatedness among males and decreased relatedness among females in the population. Finally, genetic diversity increased during the period without hunting and decreased each year when hunting was present. This study demonstrates the utility of merging demographic data with large-scale genomic datasets in order to better understand the consequences of management actions. Specifically, we believe that this study highlights the need for long-term experimental research in which hunting mortality is manipulated, including at least one non-harvested control population, as part of a broader adaptive, zone management scheme.

Colorado↗

USGS2015

Pathogen exposure varies widely among sympatric populations of wild and domestic felids across the United States

Understanding how landscape, host, and pathogen traits contribute to disease exposure requires systematic evaluations of pathogens within and among host species and geographic regions. The relative importance of these attributes is critical for management of wildlife and mitigating domestic animal and human disease, particularly given rapid ecological changes, such as urbanization. We screened >1,000 samples from sympatric populations of puma (Puma concolor), bobcat (Lynx rufus) and domestic cat (Felis catus) across urban gradients in six sites, representing three regions, in North America for exposure to a representative suite of bacterial, protozoal and viral pathogens (Bartonella sp., Toxoplasma gondii, feline herpesvirus-1, feline panleukopenea virus, feline calicivirus, feline immunodeficiency virus). We evaluated prevalence within each species, and examined host trait and land cover determinants of exposure-providing an unprecedented analysis of factors relating to potential for infections in domesticated and wild felids. Prevalence differed among host species (highest for puma and lowest for domestic cat) and was greater for indirectly transmitted pathogens. Sex was inconsistently predictive of exposure to directly transmitted pathogens only, and age infrequently predictive of both direct and indirectly transmitted pathogens. Determinants of pathogen exposure were widely divergent between the wild felid species. For puma, suburban landuse predicted increased exposure to Bartonella sp. in southern California, and FHV-1 exposure increased near urban edges in Florida. This may suggest inter-specific transmission with domestic cats via flea vectors (California) and direct contact (Florida) around urban boundaries. Bobcats captured near urban areas had increased exposure to T. gondii in Florida, suggesting an urban source of prey. Bobcats captured near urban areas in Colorado and Florida had higher FIV exposure, possibly suggesting increased intra-specific interactions through pile-up of home ranges. Beyond these regional and pathogen specific relationships, proximity to the wildland urban interface did not generally increase the probability of disease exposure in wild or domestic felids, emphasizing the importance of local ecological determinants. Indeed, pathogen exposure was often negatively associated with the wildland urban interface for all felids. Our analyses suggest cross-species pathogen transmission events around this interface may be infrequent, but followed by self-sustaining propagation within the new host species.

California, Colorado,Florida↗

USGS2012

Three pathogens in sympatric populations of pumas, bobcats, and domestic cats: Implications for infections disease transmission

Anthropogenic landscape change can lead to increased opportunities for pathogen transmission between domestic and non-domestic animals. Pumas, bobcats, and domestic cats are sympatric in many areas of North America and share many of the same pathogens, some of which are zoonotic. We analyzed bobcat, puma, and feral domestic cat samples collected from targeted geographic areas. We examined exposure to three pathogens that are taxonomically diverse (bacterial, protozoal, viral), that incorporate multiple transmission strategies (vector-borne, environmental exposure/ingestion, and direct contact), and that vary in species-specificity. Bartonella spp., Feline Immunodeficiency Virus (FIV), and Toxoplasma gondii IgG were detected in all three species with mean respective prevalence as follows: puma 16%, 41% and 75%; bobcat 31%, 22% and 43%; domestic cat 45%, 10% and 1%. Bartonella spp. were highly prevalent among domestic cats in Southern California compared to other cohort groups. Feline Immunodeficiency Virus exposure was primarily associated with species and age, and was not influenced by geographic location. Pumas were more likely to be infected with FIV than bobcats, with domestic cats having the lowest infection rate. Toxoplasma gondii s eroprevalence was high in both pumas and bobcats across all sites; in contrast, few domestic cats were seropositive, despite the fact that feral, free ranging domestic cats were targeted in this study. Interestingly, a directly transmitted species-specific disease (FIV) was not associated with geographic location, while exposure to indirectly transmitted diseases – vector-borne for Bartonella spp. and ingestion of oocysts via infected prey or environmental exposure for T. gondii – varied significantly by site. Pathogens transmitted by direct contact may be more dependent upon individual behaviors and intra-specific encounters. Future studies will integrate host density, as well as landscape features, to better understand the mechanisms driving disease exposure and to predict zones of cross-species pathogen transmission among wild and domestic felids.

PLoS ONE↗