Assessing a landscape barrier using genetic simulation modelling: Implications for raccoon rabies management

• Published in: Preventive veterinary medicine Vol. 86; no. 1; pp. 107 - 123
• Main Authors: Rees, Erin E., Pond, Bruce A., Cullingham, Catherine I., Tinline, Rowland, Ball, David, Kyle, Christopher J., White, Bradley N.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15.08.2008; Amsterdam; New York: Elsevier
• Subjects: animal diseases; animal ecology; Animals; Barrier; Computer Simulation; Demography; disease control; DNA, Mitochondrial - analysis; Female; Genetic; genetic distance; genetic simulation modelling; Genetic Variation; Haplotypes; Landscape; landscape barriers; landscape position; Male; Modelling; Molecular Epidemiology; New York; Ontario; Population Surveillance - methods; Procyon lotor; Rabies; Rabies - prevention & control; Rabies - transmission; Rabies - veterinary; Raccoon ( Procyon lotor); Raccoons - genetics; Raccoons - virology; Risk Assessment; Rivers; simulation models; Space-Time Clustering; wildlife damage management; Wildlife disease; wildlife-livestock relations; New York; Ontario; Landscape; Rabies; Genetic; Wildlife disease; Barrier; Modelling; Raccoon ( Procyon lotor)
• ISSN: 0167-5877; 1873-1716
• DOI: 10.1016/j.prevetmed.2008.03.007

Landscape barriers influence movement patterns of animals, which in turn, affect spatio-temporal spread of infectious wildlife disease. We compare genetic data from computer simulations to those acquired from field samples to measure the effect of a landscape barrier on raccoon ( Procyon lotor) movement, enabling risk assessment of raccoon rabies disease spread across the Niagara River from New York State into Ontario, an area currently uninfected by rabies. An individual-based spatially explicit model is used to simulate the expansion of a raccoon population to cross the Niagara River, for different permeabilities of the river to raccoon crossings. Since the model records individual raccoon genetics, the genetic population structure of neutral mitochondrial DNA haplotypes are characterised in the expanding population, every 25 years, using a genetic distance measure, ϕ ST, Mantel tests and a gene diversity measure. The river barrier effect is assessed by comparing genetic measures computed from model outputs to those calculated from 166 raccoons recently sampled from the same landscape. The “best fit” between modelled scenarios and field data indicate the river prevents 50% of attempts to cross the river. Founder effects dominated the colonizing genetic population structure, and, as the river barrier effect increased, its genetic diversity decreased. Using gene flow to calibrate the effect of the river as a barrier to movement provides an estimate of the effect of a river in reducing the likelihood of cross-river infection. Including individual genetic markers in simulation modelling benefits investigations of disease spread and control.