Landscape Effects on Disease Dynamics in Prairie Dogs
Investigators:
Bala Thiagarajan, Ph.D. Student
Dr. Jack Cully
Project Supervisor:
Dr. Jack Cully
Funding:
NSF, USGS, KDWP Cooperators
Sharon Collinge, Chris Ray, Ken Gage, and Michael Kosoy
Location:
Western Great Plains
Completion:
April 2007
Objectives:
Identify rodent associates of black-tailed prairie dogs, identify fleas as potential plague vectors, and identify potential routes of interspecific disease transmission.
Progress and Results:
Black-tailed prairie dogs (Cynomys ludovicianus) are epizootic hosts for plague (Yersinia pestis); however, alternate enzootic hosts are important for the maintenance of the pathogen. We determined small rodents and prairie dog associations and quantified rodent and flea relationships in the presence and absence of prairie dog colonies and plague. We identified potential alternate hosts and flea vectors for the maintenance and transmission of plague in the prairie ecosystem. This is the first multi-year study to investigate associations between prairie dogs, rodents and fleas across the range of the black-tailed prairie dog. Two rodent species associated with black-tailed prairie dogs and were found to be highly abundant on colonies. Rodent species implicated in plague were present at study areas with and without plague. Peromyscus maniculatus and Onychomus leucogaster, two widely occurring species, were more abundant on colonies and in areas with a recent history of plague. Flea community characteristics varied within each study area in the presence and absence of prairie dogs. Based on flea diversity on rodents, and the role of rodents and fleas in plague, we identified P. maniculatus and O. leucogaster and their associated fleas, Aetheca wagneri, Malareus telchinus, Orchopeas leucopus, Peromyscopsylla hesperomys, and Pleochaetis exilis to be important for the dynamics of sylvatic plague in our study areas. Peromyscus maniculatus and O. leucogaster were consistently infected with Bartonella spp., another blood parasite. Presence of prairie dog fleas on other rodents at both off and on prairie dog colonies suggests the potential for intra and interspecific transmission of fleas between rodent hosts, and between other small rodents and prairie dogs.
Products:
Peer-reviewed Publications:
Brinkerhoff, R.J., C. Ray, B. Thiagarajan, S. K. Collinge, J. F. Cully, Jr., B. Holmes, and K. L. Gage. 2008. Keystone hosts: Prairie dogs affect occurrence patterns of disease vectors on small mammals. Ecography 31:654-662.
T. Bala, Y. Bai, K. L. Gage, and J. F. Cully, Jr. 2008. Prevalence of Yersinia pestis in rodents and fleas associated with black-tailed prairie dogs at Thunder Basin National Grassland, Wyoming. Journal of Wildlife Diseases 44: 731-736.
Thiagarajan, B., J. F. Cully, Jr., T. M. Loughin, J. A. Montenieri, and K. L. Gage. 2008. Geographic variation in rodent-flea relationships in the presence of black-tailed prairie dog colonies. Journal of Vector Ecology 33:178-190.
Bai, Y., M. J. Kosoy, J. F. Cully, Jr., T. Bala, C. Ray, S. K. Collinge. 2007. Acquisition of nonspecific Bartonella strains by the northern grasshopper mouse (Onychomys leucogaster). FEMS Microbiol Ecol 61:438-448.
Thesis or Dissertation:
Bala, T. 2006. (Advisor: Cully). Community dynamics of rodents, fleas and plague associated With black-tailed prairie dogs. Ph. D. Dissertation. Division of Biology, KSU.
Presentations:
Thiagarajan, B., J. F. Cully, Jr., and K. L. Gage. 2008. Ecology of rodents and fleas associated with black-tailed prairie dogs in areas with plague. Symposium on the Ecology of plague and its effects on wildlife, Fort Collins, CO.
Bala, T., J. Cully, T. M. Loughin, Y. Bai, M. Kosoy, and K. L. Gage. Prevalence of Bartonella species in rodents and fleas associated with black-tailed prairie dogs. 62nd Annual Meeting, International Conference on Diseases in Nature Communicable to Man, Madison, WI, August 12-14, 2007.
Bala, T., Ying Bai, Micheal Kosoy, Ken Gage, Tom Loughin and J. F. Cully, Jr. 2006. Prevalence of Bartonella in rodents and fleas associated with the black-tailed prairie dogs. 55th Annual Conference of the Wildlife Disease Association, University of Connecticut, Storrs, CT.
Thiagarajan, B., and J. F. Cully, Jr. 2003. Sylvatic plague and Bartonella in small rodents associated with black-tailed prairie dogs. 58th International Conference on Diseases in Nature Communicable to Man. Flagstaff, AZ.
Thiagarajan, B., and J. F. Cully, Jr. 2003. Dynamics of sylvatic plague in black-tailed prairie dogs colonies. Kansas State University, Division of Biology 29th Annual Graduate Student Research Forum, Manhattan, KS.
