Contact structure of white-tailed deer in New York: Informing risk models and management decisions

Background/Question/Methods Managing populations at risk for contagious disease spread requires specific knowledge of disease dynamics as well as the frequency or rate of contact among individuals. Contact rates are an essential component of disease transmission and may be influenced by seasonal, behavioral, and spatial aspects of the population in question. Quantifying those rates empirically across time and space is difficult and has been limited historically by inadequate sampling. We used GPS movement data from 71 white-tailed deer to quantify potential direct (deer to deer) and indirect (deer to previously occupied space) contact rates across time and space in central New York.

Results/Conclusions We observed increased daily rates of direct contact in winter, dropping to low levels post-parturition through summer, and increasing during the rut to winter levels. Spatial contact structures resulted in distributions of primary contact probabilities across space which may inform managerial decisions for assessing risk and allocating resources in response to disease detection. Spatial contact structures were consistent across seasons, suggesting that despite seasonal differences in contact rates, those contacts occur proportionally across similar landscape extents.