Loading…
US-IALE 2018 has ended
Back To Schedule
Tuesday, April 10 • 11:15am - 11:30am
INVASIVE SPECIES: Fire Regimes, Plant Invasions, and Tick-Borne Disease Risk Across a Climate Gradient in the Southeast U.S.

Sign up or log in to save this to your schedule, view media, leave feedback and see who's attending!

AUTHORS: Whalen W. Dillon*, University of Florida; Brian F. Allan, University of Illinois; Michael C. Dietze, Boston University; S. Luke Flory, University of Florida

ABSTRACT: Ecological theory predicts that climate change will alter vector-borne disease risk through a variety of direct and indirect pathways, but the relative importance of various pathways is poorly understood for most systems. We are exploring several factors hypothesized to affect the risk of exposure to tick-borne diseases (TBDs) on Department of Defense (DoD) installations along a gradient of climatic conditions across the southeastern United States. Specifically, we are examining the effects of fire regimes and plant invasions on abundances of ticks and wildlife hosts, focusing on non-native cogongrass (Imperata cylindrica) and the lone star tick (Amblyomma americanaum). Our overarching hypothesis is that fire and plant invasions are dominant factors directly and indirectly affecting exposure risk to TBDs on DoD installations in this region. In the first year of this multi-year study we visited six DoD installations, collecting data on forest structure, the plant community, and abundances of ticks and wildlife hosts at 29 plots primarily in pine-dominated landscapes varying from 0 to 11 years since the last prescribed fire. Cogongrass management efficacy on DoD installations limited the number of untreated invaded areas to eight plots, with six of these burned less than three years prior. Tick-host abundance was greater at 0-1 years than 2+ years, following fire. Tick abundance was greater in uninvaded plots, increasing with time since fire, litter cover, and over-story canopy cover. Climate effects based on the latitudinal gradient of installations weren’t detectable in our preliminary data set. Our initial results provide evidence suggesting that fire and forest vegetation and structure have significant effects on TBD risk as we predicted. Frequent prescribed fires are a typical management goal to maintain pine ecosystems, and we show the additional benefit of lowering TBD risk by reducing canopy and litter cover.

Tuesday April 10, 2018 11:15am - 11:30am CDT
Spire Parlor

Attendees (3)