Mammal Species of the World
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Onychomys leucogaster, the Northern grasshopper mouse, can be found from southwestern Canada throughout the western United States into northwestern Mexico. Its distribution ranges from the Pacific coast to western Minnesota and Iowa.
Biogeographic Regions: nearctic (Native )
Regularity: Regularly occurring
Type of Residency: Year-round
Regularity: Regularly occurring
Type of Residency: Year-round
Global Range: South-central Canada (southern Alberta, Saskatchewan, and southwestern Manitoba) south through the Great Plains to northern Tamaulipas, Mexico. Extends west through the Great Basin and southwestern deserts of Arizona and New Mexico, and also occurs in the Rocky Mountains. See Riddle and Choate (1986) and Riddle (1995) for information on biogeography.
Northern grasshopper mice have white ventral fur, and dorsal fur that ranges from brown to pink. The tail is short, averaging 42 mm in length, with a white tip. This is approximately one third of total body length, which averages 164mm. The hind feet average 22mm.
Juvenile O. leucogaster have white ventral surfaces, however the dorsal fur ranges from light to dark grey. At 57 to 62 days of age, fur color changes to the cinnamon color of adult pelage. This process takes up to 20 days. Teeth are smaller than many other mice, with pointed cusps reflecting their carnivorous diet.
Range mass: 25 to 40 g.
Other Physical Features: endothermic ; bilateral symmetry
Length: 19 cm
Weight: 52 grams
Size in North America
Range: 119-190 mm
Range: 26-49 g
Onychomys leucogaster live in shortgrass prairies, sand dunes and in sage brush desert. These are primarily areas with sandy soil in which they build their burrows. Compared to other species of the same genus, northern grasshopper mice prefer higher elevations and so are also commonly found in canyon lands.
Terrestrial Biomes: desert or dune ; savanna or grassland
Habitat and Ecology
Comments: Occurs in grasslands, prairies, sagebrush deserts, overgrazed pastures, weedy roadside ditches, and semi- stabilized sand dunes; areas with sandy, diggable soil and sparse vegetation. Occupies underground burrows when inactive. Young are born in U-shaped nest burrow at a mean depth of 14 cm below the surface.
Non-Migrant: Yes. At least some populations of this species do not make significant seasonal migrations. Juvenile dispersal is not considered a migration.
Locally Migrant: No. No populations of this species make local extended movements (generally less than 200 km) at particular times of the year (e.g., to breeding or wintering grounds, to hibernation sites).
Locally Migrant: No. No populations of this species make annual migrations of over 200 km.
O. leucogaster are unique among mice in that the majority (almost 90%) of the diet is other animals. They feed primarily on insects, including grasshoppers, scorpions, beetles, crickets, and moths. They have been known to eat rodents as well, including other O. leucogaster.
Northern grasshopper mice stalk their prey in an almost feline manner letting out a shrill cry before attacking.
In the stomach of these creatures, two of the glands are enclosed in a 'pocket' of tissue. This is thought to protect them from damage by the chitin from their insect prey.
Comments: Eats primarily animal material (70-90%), mostly arthropods (grasshoppers, beetles, spiders, larval Lepidoptera), also occasionally small rodents in winter. Plant matter is eaten, especially in winter, when insects unavailable; at that time may store seeds.
Usually occurs at relatively low densities, but may become a controlling factor for its prey items. Shrill whistles given on spring and summer nights, perhaps as territorial defense. Unusually large home range (estimated average 2.3 ha) for a small mammal.
Life History and Behavior
Perception Channels: tactile ; chemical
Comments: Active throughout the year, although activity is greatly reduced during a full moon or heavy, prolonged rainfall.
Status: captivity: 5.0 years.
Lifespan, longevity, and ageing
Breeding occurs throughout the year but more frequently between May and October.
When a male and female O. leucogaster come within 10 to 15 cm of each other, they begin to circle and smell the anal area of the other sex. This is followed with the male following the female until he mounts her from the rear in what is called a copulatory lock. This occurs in 10 phases and requires around three hours to complete. Each phase is ended when the female moves away and begins to groom herself. Studies show that pairs that engage in only a few "locks" have little reproductive success.
The female rears an average of four young which she spends much time caring for until they are 14 days old. The male does not contribute to this care. This is a relatively slow maturation rate and is thought to be connected to learning the predatory behaviors that the young will need to survive. Several litters are born to a female each year.
Key Reproductive Features: gonochoric/gonochoristic/dioecious (sexes separate); sexual
Average birth mass: 2.6 g.
Average gestation period: 31 days.
Average number of offspring: 4.
Average age at sexual or reproductive maturity (male)
Sex: male: 114 days.
Average age at sexual or reproductive maturity (female)
Sex: female: 100 days.
Sexual activity begins at 3 or 4 months of age. Gestation lasts about 32-38 days. Most litters are born February-October, with a peak in June, July, and August. Litter size is 1-6. In the laboratory, up to six litters per year may be produced.
Molecular Biology and Genetics
Statistics of barcoding coverage: Onychomys leucogaster
Public Records: 0
Specimens with Barcodes: 8
Species With Barcodes: 1
US Federal List: no special status
CITES: no special status
IUCN Red List of Threatened Species: least concern
IUCN Red List Assessment
Red List Category
Red List Criteria
National NatureServe Conservation Status
Rounded National Status Rank: N4 - Apparently Secure
Rounded National Status Rank: N5 - Secure
NatureServe Conservation Status
Rounded Global Status Rank: G5 - Secure
Relevance to Humans and Ecosystems
In shortgrass prairies northern grasshopper mice add prairie birds to their diet. This may result in the loss of a variety of birds because of predation by this species and other mammalian predators.
Since the diet of this species consists of mainly insects and very few plants (such as commercially produced grains), it has been suggested that O. leucogaster may be able to serve as a natural predator against pests that commonly disturb agriculture.
They also make interesting pets, and become tame in captivity.
The northern grasshopper mouse, or killer 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 central Saskatchewan and central Washington to Tamaulipas in northeast Mexico.
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 164 mm (6.5 in) long and about 35 g (0.077 lb) 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 carnivorous diet mainly consisting of small insects, other mice, and even snakes. This rodent is also nocturnal, unlike most of its kind. Throughout the night, the grasshopper mouse makes high-pitched noises to claim its territory.
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. 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.
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. 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.
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) 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. 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. They are also found frequently infected with another hemotropic intracellular pathogen Bartonella and Ying et al. 2007 showed that they can acquire different strains of Bartonella from multiple rodent species.
- Linzey, A. V.; Timm, R. (2008). "Onychomys leucogaster". IUCN Red List of Threatened Species. Version 2014.2. International Union for Conservation of Nature. Retrieved 30 August 2014.
- "The Living Edens: Canyonlands: America's Wild West". PBS. Retrieved 2009-01-14.
- Musser, G. G.; Carleton, M. D. (2005). "Superfamily Muroidea". In Wilson, D. E.; Reeder, D. M. Mammal Species of the World (3rd ed.). Johns Hopkins University Press. p. 1061. ISBN 978-0-8018-8221-0. OCLC 62265494.
- 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.
- 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.
- 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.
- 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.
- 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.
- Ying, 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.
Names and Taxonomy
Comments: Onychomys mtDNA-haplotypes define at least five discrete geographical subsets (Wyoming Basin/Interior Plains/Colorado Plateau, Columbia Basin/Great Basin, Gulf Coastal Plain, Chihuahuan Desert, and Western Deserts), corresponding with five inferred areas of endemism for biota restricted to arid and semiarid habitats in North America (Riddle and Honeycutt 1990). See Riddle and Choate (1986) for subspecific revisions.