Climate change and its impact on parasite range and abundance is a major driver of wildlife and ecosystem health. Describing how climate change is affecting parasite-host systems through changes in parasite behavior and survival probability can help wildlife managers target practices toward specific high-risk habitats or time periods. This project will use a classic hierarchical field acarology study alongside an experimental deployment study to understand how microclimate conditions and habitat affect winter tick distribution and survival in Northwestern Wyoming. Winter ticks (Dermacentor albipictus) are a serious pest for moose (Alces alces) across the southern extent of their range, but the winter tick-moose system has yet to be well-described in montane ecosystems. Climate change may be affecting winter tick populations through two major avenues: changing host behavior and physiology or changing environmental variables that then influence tick survival. In this study we will collect questing ticks across a range of habitats, microclimate conditions, and in areas with different moose densities and migration statuses while also conducting an experimental deployment study to determine the habitat and microclimate conditions associated with winter tick survival and questing larva rates.
Results/Conclusions
Twenty fed adult female ticks will be deployed in each of 50 experimental plots across a range of habitats and microclimate conditions in Spring 2020. Questing larva abundance will be quantified the following Fall. Microclimate conditions will be monitored throughout the deployment period and later used in climate prediction models to estimate temporal risk to winter tick infestations. Additionally, a wider winter tick detection study during the Fall larval questing period will describe distribution and relative abundance of winter ticks across a range of habitats and microclimate conditions. Areas surveyed will also differ in the density of local moose herds and their migratory status. Together, these studies will identify the conditions where winter ticks are more likely to occur, which conditions they best survive in, and whether those conditions or some aspect of moose density or migration status better explain their distribution and abundance. These data will ultimately be informative for moose managers in montane ecosystems but also demonstrate how incorporating both host and parasite responses to climate change will better describe how these systems may change in the future.