To Flea or Not To Flea: Abiotic and Biotic Factors Driving Flea Parasitism on Wild Deer Mice

Author

• Parker Todd, University of Montana, MissoulaFollow
• Angela Luis, University of Montana, MissoulaFollow
• Mike Kinsella, Helm West LabFollow

Graduation Year

2026

Graduation Month

May

Document Type

Thesis

Degree Name

Bachelor of Science – Forestry

School or Department

Forestry and Conservation

Major

Wildlife Biology – Terrestrial

Faculty Mentor Department

Department of Ecological and Conservation Sciences

Faculty Mentor

Angela Luis

Keywords

Fleas, Hantavirus, Peromyscus maniculatus, Ectoparasites, Host-Parasite Relationships

Subject Categories

Terrestrial and Aquatic Ecology

Abstract

Deer mice (Peromyscus maniculatus) are an abundant North American rodent and the primary reservoir for Sin Nombre virus (SNV), a hantavirus with a 30-40% case fatality rate in humans. While ectoparasites, such as fleas, are not considered vectors of SNV, their bites may indirectly affect the transmission of SNV by impacting host condition or immune function. These impacts could potentially lead to an increase in host susceptibility and/or an increase in viral shedding, yet there is still little knowledge on what influences flea parasitism on deer mice in western Montana. This study looks to examine how mouse sex, mouse body mass, soil moisture, and soil temperature affect the presence and number of fleas in two populations of deer mice at MPG Ranch in Florence, Montana. For this study, I used preserved carcasses that were collected as a part of a longitudinal trapping effort at UM that took place from 2023-2025 with soil moisture/temperature being logged every 30 minutes at each site. Each mouse was individually examined for fleas. Preliminary results show that 154 of 546 (28%) mice were parasitized. We identified 266 total fleas to species and found 9 different species, 2 of which are species not commonly found in this area.

We analyzed the data using Generalized Linear Mixed Models to assess how biotic and abiotic factors are influencing the presence and abundance of fleas. These analyses will provide insight on the patterns of flea infestation on wild deer mice in Montana.

GLI Capstone Project

no

Recommended Citation

Todd, Parker; Luis, Angela; and Kinsella, Mike, "To Flea or Not To Flea: Abiotic and Biotic Factors Driving Flea Parasitism on Wild Deer Mice" (2026). Undergraduate Theses, Professional Papers, and Capstone Artifacts. 595.
https://scholarworks.umt.edu/utpp/595