Project Title:
Community Dynamics of Micromammals and their Resident Ectoparasites

Project Description (short):
Tick species show preference in what host they choose to parasitize. This preference may affect survival and tick population growth if the size of the host population changes. Data from our studies in Adair County, indicate that Peromyscus is the most common mouse and that this species is a very important host for larval Dermacentor variabilis (dog tick). The specific objective of this project is to determine if there is a relationship in the patterns of population dynamics in Permoysucs and D. variabilis. We will address this objective by analyzing and adding to our multi-year data of rodent and tick populations. Students involved in this research will learn a variety of field and statistical methods. (Longer description here.)

Skills needed:
Both students will need to demonstrate the following:

• The ability to conduct field work under arduous environmental conditions.
• Willingness to handle and sacrifice small mammals, ticks and other parasites of small mammals.
• Willingness to engage problems and issues outside their discipline.
• Willingness to follow directions and execute independently.
• Willingness to work as a member of an interdisciplinary team.

Biology:

• Required Coursework:, STAT190 (Introduction to Statistics)
• Preferred Coursework: BIOL 301 (Introduction to Ecology)
• Preferred Experience: Handling and sacrificing insects and small mammals

Mathematics Students:

• Required Coursework: STAT 290 (Introduction to Statistics)
• Preferred Coursework: STAT 378 (Regression), STAT 375 (ANOVA), STAT 570/571 (Mathematical Statistics), BIOL 100 (General Biology)
• Preferred Experience: SPSS, R, Excel, SAS

Start Date:
January 2009

End Date:
August 2009 or later

Mentors:
Prof. Stephanie Foré (Biology), sfore@truman.edu
Prof. Hyun-Joo Kim (Statistics), hjkim@truman.edu

Current RLC Students:

• Tad Dallas (Biology)
• Will Petry (Biology)
• Georgia Mueller (Mathematics)

About Prof. Foré:
Dr. Foré has resided in Kirksville for eleven years, the longest she has lived in any one place or state. She received her B.S. in Biology from St. Andrews Presbyterian College, a very small liberal arts school, a M.S. in Plant Pathology from North Carolina State University and a Ph. D. in Botany from Miami University. Before coming to Truman she did postdoctoral work in the Department of Zoology at Miami University and was a Research Ecologist at Savannah River Ecology Laboratory. She is transitioning from primarily plant population biology to animal population/community ecology and is enjoying her collaboration with Dr. Fielden and Dr. Kim and many wonderful students. She loves to take long walks in wild, unpopulated places, spin and dye her own yarn which she then knits, and eat richly spiced food and therefore has learned to cook ethnic food.

About Prof. Kim:
Dr Kim was born and raised in Seoul Korea. She completed her M.S. (1998) and Ph.D.(2000) in Statistics department at the University of Missouri-Columbia. She is interested in various applied statistics including statistical modeling, model selection criteria, Biostatistics, computational statistics, longitudinal statistics, and Bayesian statistics. She has enjoyed MathBio undergraduate research program working as a team of Biology faculty and students and Mathematics/Statistics faculty and students. She has a three and a half year old daughter (Juni) and a one and half old son (Minu). She enjoys doing yoga, walking, eating Korean food and cuddling with her kids.

She has a two and a half year old daughter (Juni) and a four month old son (Minu) who claims most of her free time. She enjoys doing yoga, walking, eating Korean food and cuddling with her kids.

Project Description (long):

Dynamics in the communities of small mammals and ticks is likely interdependent. Both rodents (Swihart and Slade 1990, Brady and Slade 2004, Calisher et al. 2005) and ticks have been demonstrated to have annuals peaks (Sonenshine 1993, Sonenshine et al. 1966). Interannual trends in rodent populations, revealed from a six year study (Calisher et al. 2005b), have been attributed to the interaction between temperature and precipitation. Previous work in our lab has shown that there are a variety of small mammals in our study sites at the Truman State University farm. The most common species is Peromyscus leucopus, but the communities also include other rodents and shrews.

Mammal community dynamics (changes in abundance of different mammal species over time) are likely to be important in determining tick population size from year to year as changes in the number of potential hosts are likely to impact tick success in finding a host. We have collected three species of ticks, Dermacentor variabilis, Ambylomma americanum and Ixodes scapularis, living off-host. However, we have found the larval and nymphal stages of only one of these species, D. variabilis, on rodents. No ticks have been observed on shrews. Although A. americanum is the most common tick in these habitats and I. scapularis is known to use rodents as a host, none have been observed in our two year data set on rodents.

The specific objective of this project is to determine if there is a relationship in the patterns of population dynamics in Permoysucs and D. variabilis populations. For the past several years our lab group has been monitoring the populations of small mammals and ticks on and off-host in two different habitats. We will continue the monitoring of these populations and work to analyze this growing body of data. Understanding the relationship in the dynamics of these different populations can lead to models that predict the size of dog tick populations. As the dog tick is a vector of several diseases of human and veterinarian importance, such of model would be useful in predicting disease risks.

Methods:

To address these questions we use mark-recapture to estimate the number of Peromyscus over short periods (days) and longer periods (months) of time. Seasonal and daily patterns of activity of ticks off host are assessed by drag sampling and/or bait stations. Meteorological variables, such as temperature and humidity, will be assessed at the regional scale.

References:

• Brady, M.J. and N.A. Slade. 2004. Long-term dynamics of a grassland rodent community. J Mammalogy 85: 552-561.
• Calisher, C.H., J.N. Mills, W.P. Sweeney, J.J. Root, S.A. Reeder, E.S. Jentes, K. Wagoner and B.J. Beaty. 2005. Population dynamics of a diverse rodent assemblage in mixed grass-shrub habitat, southeastern Colorado, 1995-2000. JWildlife Dis 41: 12-28.
• Sonenshine, D.E. 1993. Biology of Ticks. Vol 2 New York, Oxford University Press.
• Sonenshine, D.E., E.L. Atwood and J.T. Lamb, Jr. 1966. The ecology of ticks transmitting Rocky Mountain spotted fever in a study area in Virginia. Ann Entomol Soc Amer 59 (6): 1234-1262.
• Swihart, R.K., and N.A. Slade. 1990. Long-term dynamics of an early successional small mammal community. Amer Midl Nat 123: 372-382.