Pennsylvania Project: Linking Genetics to Movements of White-tailed deer to Assist Surveillance for CWD Epidemiology

Pennsylvania Project

Linking Genetics to Movements of White-tailed deer to Assist Surveillance for CWD Epidemiology

July 2019 - August 2024

Personnel

Participating Agencies

Pennsylvania Game Commission
Ecosystem Mission Area, Disease Cyclical Funds

Surveillance for chronic wasting disease (CWD) in deer is often in response to finding a new disease foci with direction of surveillance controlled by some arbitrary distanced buffer around a diseased animal. Understanding large-scale gene flow across a region can identify the most likely transmission path of CWD because gene flow identifies historic ancestry of deer across a landscape. Combining landscape genetics with CWD surveillance would provide natural resource agencies a more structured approach to surveillance by providing disease units more reflective of the underlying subpopulation structure of deer in a region.

Research Publications

Research Publications	Publication Date
Bauder, J.M., C.S. Anderson, H.L. Gibbs, M.J. Tonkovich, and W.D. Walter. 2021. Landscape features fail to explain spatial genetic structure in white-tailed deer across Ohio, USA. Journal of Wildlife Management 85(8):1669-1684. DOI: 10.1002/jwmg.22120 \| Abstract \| Publisher Website	October 2021	Landscape features influence wildlife movements across spatial scales and therefore have the potential to influence the spread of disease. Chronic wasting disease (CWD) is a fatal prion disease affecting members of the family Cervidae, particularly white-tailed deer (<i>Odocoileus virginianus</i>), and the first positive CWD case in a wild Ohio deer was recorded in 2020. While landscape genetics approaches are increasingly utilized to better understand potential pathways for CWD spread in white-tailed deer, little is known about genetic structure of white-tailed deer in Ohio. The objectives of our study were to evaluate spatial genetic structure in white-tailed deer across Ohio and compare the support for isolation by distance (IBD) and isolation by landscape resistance (IBR) models in explaining this structure. For genetic data we used microsatellite genotypes from 619 individuals from 24 counties across Ohio genotyped at 11 loci and a 547-bp fragment of the mitochondrial DNA Control Region from the same individuals. We used spatial and non-spatial genetic clustering tests to evaluate genetic structure in both types of genetic data and empirically optimized landscape resistance surfaces to compare IBD and IBR using microsatellite data. Non-spatial genetic clustering tests failed to detect spatial genetic structure while spatial genetic clustering tests indicated subtle spatial genetic structure. IBD models consistently outperformed IBR models including land cover, traffic volume, and streams. Our results indicated widespread genetic connectivity of white-tailed deer across Ohio and negligible barrier effects of landscape features. These patterns likely reflect some combination of minimal resistive effects of landscape features on white-tail deer movement in Ohio and the effects of regional recolonization or translocation. We encourage continued CWD surveillance in Ohio, particularly in the proximity of confirmed cases.

Presentations

Presentations	Presentation Date
Fameli, A., C.S. Rosenberry, K.L. Schuler, M.J. Tonkovich, J.E. Edson, and W.D. Walter. 2024. Large-scale assessment of genetic structure of white-tailed deer: applications to genetic assignment tests. Joint Meeting of The Pennsylvania Chapter of Wildlife Society and the Pennsylvania Biological Survey, State College, PA, 22-23 March 2024.	March 2024

Cooperative Fish and Wildlife Research Units Program: Pennsylvania Education, Research and Technical Assistance for Managing Our Natural Resources