Meeting Abstract
Documenting potential vector species is an important first step in understanding the dynamics of vector-borne diseases. Plague, caused by Yersinia pestis, is a bacterial disease transmitted by multiple flea species, which are hosted by a variety of small mammals. In the Sierra Nevada mountains, sciurids and their fleas are important in the maintenance and transmission of plague. While many of these species are regularly tested for plague, in some cases relatively little is known about the specific ectoparasite assemblages they host. In particular, flea communities of the lodgepole chipmunk (Tamias speciosus) and especially the alpine chipmunk (T. alpinus) have been characterized infrequently, and usually with low sample sizes. These species are not primary transmitters of plague – though T. speciosus is known to transmit and succumb to the disease – however, they are of broad interest because they have exhibited divergent elevational range shifts over the past century, possibly due to climate change. Therefore, characterizing ectoparasitism in these species may shed light on the dynamics of flea infestation and disease transmission in changing environments. Here we report results from a study of T. alpinus (N=298) and T. speciosus (N=1014) trapped and combed for fleas in 2013-2015. The primary goals are to characterize the relationships between flea species and abundance and (1) host species; (2) host endogenous factors (species, sex, mass, behavior); (3) environmental factors (temperature, habitat). Ultimately, this study will help to establish ecological baselines for the focal species and will clarify the relationships between host, fleas, and environment in a plague- and climate-change-relevant system.
