Onychomys leucogaster

The northern grasshopper mouse (''Onychomys leucogaster'') is a North American carnivorous rodent of the family Cricetidae. It ranges over much of the western part of the continent, from southern Saskatchewan and central Washington to Tamaulipas in northeast Mexico.

Background information

The northern grasshopper mouse is found in North America, but primarily in dry areas. They are similar in body size to other mice; on average they are long and about in weight. The tail is most often less than 30% of the total body length, whereas other mice tend to have longer tails adding to long body lengths. The grasshopper mouse is a reddish-black/grey color with white hair on the belly. Unlike most rodents, this one has a mostly carnivorous diet mainly consisting of small insects, other mice, and even snakes; no more than a quarter of its diet is plant-based. This rodent is also nocturnal. Throughout the night, the grasshopper mouse makes high-pitched noises to claim its territory.

Habitat

This grasshopper mouse can be found in prairies with low grass, dry areas, and also pasture lands of the central and southwestern parts of the United States. ''O. leucogaster'' has been known to associate positively with black-tailed prairie dogs, possibly due to their preference for disturbed areas, suitable habitat in the form of burrows, or food supply.Choate, J. R. and D. M. Terry. 1974. Observations on habitat preference of Onychomys leucogaster (Rodentia: Muridae) on the central Great Plains. Transactions of the Kansas Academy of Science 76:263-265.Stapp, P. 1997. Habitat selection by an insectivorous rodent: patterns and mechanisms across multiple scales. Journal of Mammalogy 78: 1128-1143.Bala Thiagarajan. 2006
Community dynamics of rodents, fleas and plague associated with the black-tailed prairie dogs
Doctoral dissertation submitted to Kansas State University. The northern grasshopper mouse lives in burrows underground, by either digging its own or inhabiting burrows that have been disowned. These mice have a system of multiple burrows, with each burrow serving a different function. The nest burrow is the primary area of activity during the day; since they are nocturnal, they do not need to be in a burrow during the night. To keep moisture in during the day, they close up the opening. A retreat burrow serves for quick escape from predators. Its design is about 10 inches into the ground at a 45° angle. The cache burrow is used for storing seeds. The signpost burrows are small and filled with glandular secretions that mark the boundaries of their territory. All of these burrows are found within a large area of territory.

Reproduction

The northern grasshopper mouse has about two or three litters a year consisting of two to seven young, with the average being four. They have a gestation of 32–47 days, and the young are born in either late fall or early winter, between September and February. The male gathers and provides food for the female while she is pregnant and taking care of her young.Burt, W.H., R.P. Grossenheider. 1976. The Peterson Field Guide Series: A Field Guide to the Mammals. Peterson, R.A. (Ed.). Houghton Mifflin Company, Boston, p.166-67. The northern grasshopper mouse is an altricial species; baby mice are naked with closed eyes when they are born, and weigh about three grams. Both sexes reach their sexual maturity at three months, but the lifespan of a typical mouse living in the wild is only a few weeks to a few months.

Diseases

Susceptibility studies on grasshopper mice from areas with plague and from those areas that have been historically free of plague by Thomas et al. (1988)Thomas, R. E., A. M. Barnes, T. J. Quan , M. L. Beard , L. G. Carter, and C. E. Hopla. 1988. Susceptibility to ''Yersinia pestis'' in the northern grasshopper mouse (Onychomys leucogaster). Journal of Wildlife Diseases 24:327–33. showed the animals from areas with a history of plague were more resistant to the plague bacterium ''Yersinia pestis'' than the animals from a historically plague-free area, hence they were considered to be a potential alternate host for plague. Grasshopper mice have also been shown to harbor 57 species of fleas, many of which are vectors of plague.6) Thomas, R. E. 1988. A review of flea collection records from ''Onychomys leucogaster'' with observations on the role of grasshopper mice in the epizoology of wild rodent plague. Great Basin Naturalist 48: 83-95. Given the abundance and diversity of fleas on the grasshopper mouse and their use of prairie dog burrows and interaction with other rodent species, they are considered to be important for the maintenance and transmission of plague in the prairie dog ecosystem.Gage, K. L., and M. Y. Kosoy. 2005. Natural history of the plague: perspectives from more than a century of research. Annual Review of Entomology 50:505 - 528. They are also found frequently infected with another hemotropic intracellular pathogen ''Bartonella'' and Ying et al. 2007Ying, B., M. Kosoy, J. F. Cully, T. Bala, C. Ray, AND S. Collinge. 2007. Acquisition of non-specific ''Bartonella'' strains by the northern grasshopper mouse (''Onychomys leucogaster''). FEMS Micro. Ecol. 61 (3): 438–448. showed that they can acquire different strains of ''Bartonella'' from multiple rodent species.

References

External links

The Mammals of Texas - Online Edition Entry

{{Taxonbar, from=Q1769900

Onychomys
Mammals described in 1841