Great Basin Naturalist


Published records of fleas collected from the northern grasshopper mouse, Onychomys leucogaster, indicate that these mice have a great deal of intimate environmental contact with other rodents or their burrows. Fifty-seven species of fleas have been collected from the omnivorous grasshopper mouse. The range of this mouse overlaps much of the distribution of plague, Yersinia pestis, in the western United States; and nearly one-half of the flea species collected from O. leucogaster are known to be of importance in the epizoology of plague. This article discusses the importance of the association of fleas with a hospitable secondary host in the maintenance and transmission of wild rodent plague.