Inter-annual home range fidelity of wild and ranched white-tailed deer in Florida: implications for epizootic hemorrhagic disease virus and bluetongue virus intervention

Epizootic hemorrhagic disease virus (EHDV) and bluetongue virus (BTV) are vector-borne orbiviruses affecting ranched and wild white-tailed deer ( Odocoileus virginianus ) in North America. Currently, limited data exist on EHDV and BTV transmission dynamics in ranched and wild herds. To identify long-term site-specific EHDV and BTV intervention strategies (e.g., integrated pest or animal husbandry management), it is important to understand inter-annual home range fidelity (site fidelity). This study examined inter-annual site fidelity of ranched and wild deer in FL, USA. We estimated and compared inter-annual site fidelity of individual ranched and wild deer during the EHDV and BTV transmission season (May 1–October 31) for two consecutive years. GPS collars were attached to 11 wild and 4 ranched animals. Inter-annual site fidelity was calculated using the overlap function in the continuous-time movement modeling (ctmm) package in R, which estimates a Bhattacharyya coefficient (BC) between years. BC values range from 0 to 1, with values closer to 1 representing high degrees of overlap (site fidelity) between annual home ranges. The mean BC overlap was 0.876 (± 0.056 SE) and 0.831 (± 0.108 SE) for wild and ranched animals, respectively. We observed high levels of inter-annual site fidelity for 10 of 11 wild deer and 3 of 4 ranched deer. High inter-annual home range fidelity suggests EHDV and BTV intervention strategies, such as food plot (wild, ranches) or feeder (ranches) movements, or exclusion fencing to reduce deer time in vector habitat, may have multi-year impacts.