Order RodentiaFamily Cricetidae

• Diastema• 1 pair incisors• Ears shorter than tail• Eyes, ears visible• Tail with fur, or

laterally flattened; not bushy

• Tail shorter than head and body

Peromyscus leucopus

Reithrodontomys megalotis

Identification: Long bicolored tail; fur bristly, short; dorsum yellow-brown to gray; venter white; upper incisor face grooved

Distribution: Statewide

Habitat: Grassy habitats; spherical nest of grasses, fibers, down

Reithrodontomys megalotis

Diet: Seeds, grains, herbaceous vegetation; some invertebrates

Reproduction: Up to 14 litters of 1-9 annually

Conservation: Fairly common

Peromyscus maniculatus bairdii

Identification: Large eyes; fur not very bristly; incisors lack grooves; bicolored tail; dorsum brown to gray; dorsum white (TL 125-160 mm)

Distribution: Statewide

Habitat: Grassy and brushy areas; early invader of disturbed habitat (e.g., tilled fields)

Peromyscus maniculatus bairdiiDiet: Grains, invertebrates

Reproduction: Several litters of 1-11 annually

Conservation: Very abundant

Other: Most common carrier of Hantavirus Pulmonary Syndrome

Peromyscus leucopusIdentification: Large eyes; fur not very bristly; incisors lack grooves; bicolored tail in winter; dorsum brown to gray; dorsum white (TL 160-200)

Distribution: Statewide

Habitat: Tall weedy, brushy, wooded habitat

Peromyscus leucopus

Diet: Nuts, seeds, berries, invertebrates

Reproduction: Several litters of 1-7 annually

Conservation: Common

Other: Carrier of Hantavirus Pulmonary Syndrome

Clethrionomys gapperiIdentification: Small eyes,

ears; dorsum with reddish stripe flanked by gray; venter grayish to white

Distribution: Northern Iowa

Habitat: Cold, moist forests and open wet areas; tunnel under logs

Clethrionomys gapperiDiet: Nuts, seeds, berries,

herbaceous vegetation, some invertebrates

Reproduction: Multiple litters of 2-10

Conservation: Endangered; likely survives only in Pilot Knob State Park, Hancock County

Microtus pinetorumIdentification: Small eyes

and ears; tail longer than hind foot, and up to 29 mm; fur soft and velvety; dorsum reddish to reddish brown

Distribution: Statewide

Habitat: Old-growth forest

Microtus pinetorumDiet: Nuts, seeds, roots,

grasses, bark

Reproduction: Multiple litters of up to 3 young

Conservation: Uncommon

Microtus ochrogaster

Identification: Small eyes and ears; tail usually > 29 mm; fur long and coarse; dorsum brown to gray with salt-and-pepper appearance; venter usually yellowish; tail somewhat bicolored; molars with 5,4,4 islands of dentine

Distribution: Statewide

Habitat: Dry, grassy areas

Molars

Microtus ochrogasterDiet: Green vegetation, roots,

seeds, bark

Reproduction: Multiple litters of 1-7

Conservation: Generally common, uncommon in east Iowa; probably declining due to agriculture

Microtus pennsylvanicus

Identification: Small eyes, ears; tail usually longer than 29 mm; fur soft; dorsum brown to gray with salt-and-pepper appearance; venter usually gray; 3 molars with 5,5,5-6 islands of dentine

Distribution: Statewide

Habitat: Moist grassy areas

Molars

Microtus pennsylvanicusDiet: Green vegetation, seeds

Reproduction: Multiple litters of 1-11

Conservation: Very abundant; probably increasing; densities may reach 100 per acre

Order RodentiaFamily Muridae

Kristin Myers

The Mammals of Texas - Online Edition

Onychomys leucogaster: Northern Grasshopper Mouse

Identification: stout body; drab brown dorsally, white ventrally; stout, bicolored tail with a white tip, usually less than 1/3 of TL

http://www.enature.com/fieldguide/showSpeciesFT.asp?fotogID=942&curPageNum=15&recnum=MA0087

Distribution: The Loess Hills

Habitat: Shortgrass prairies, sand dunes and sage brush desert. Build burrows in sandy soil; prefer higher elevations

Diet: Insects such as grasshoppers, Diet: Insects such as grasshoppers, crickets, scorpions and beetles; other crickets, scorpions and beetles; other grasshopper micegrasshopper mice

Reproduction: Year round but mainly May-Oct. Give birth to usually 4 young in several litters annually. Males do not care for the young.

http://animaldiversity.ummz.umich.edu/site/accounts/information/Onychomys_leucogaster.html

Conservation status: Threatened

Other: Stalk their prey like a feline and let out a shrill cry before attacking.

http://jagor.srce.hr/XIIIgim/pictures/rodents/northern_grasshopper_mouse.jpg

References

• National Wildlife Federation. ENature. Available at http://www.enature.com/fieldguide/showSpeciesFT.asp?fotogID=942&curPageNum=15&recnum=MA0087

• The University of Michigan Museum of Zoology. Animal Diversity Web. Available at http://animaldiversity.ummz.umich.edu/site/accounts/information/Onychomys_leucogaster.html

• Sevilleta LTER Data. Available at http://sevilleta.unm.edu/data/species/mammal/sevilleta/profile/northern-grasshopper-mouse.html

Ondatra zibethicusMuskrat

Elizabeth Yoder

Identification

• Semiaquatic• Tail laterally

compressed, nearly hairless and scaly

• Large hindfeet, partly webbed

• Smaller than beaver

Identification continued

• Upper pelage dark, dense, and glossy

• Flanks are paler• Underparts silvery

gray

Measurements

• Total length= 470-630 cm

• Tail= 200-260 cm• Hindfoot= 70-90 cm• Weight= .7-1.5 kg

Distribution

• Statewide• From Alaska and

Labrador south to northernmost Mexico

Habitat

• Streams, ponds, lakes, marshes, sloughs

• Home range within 200 yards of den

• Average 1 Ondatra zibethicus per 15 acres

• Modify habitat

Diet

• Omnivore• Plants, stems, leaves,

bulbs, roots of aquatic plants, fish, frogs, crayfish, snails

• Nocturnal feeder of aquatic plants

• Feeding huts• Swim and forage under ice

Reproduction

• Polygamous• Breed March- July• 2-4 litters• 2-9 young per litter• Gestation 29-31 days• 8 weeks weaned from

mother

Reproduction continued

• Conical dens of aquatic plants and mud

• Built in shallow water, islands, or along banks

• Bank burrows• Smaller den than

beaver

Conservation Status

• Abundant

Other…

• Valuable furbear• >1 million hunted for pelts

in North central states each winter

• Pelt=$5• Territioral, vicious fighter• Swim submerged for 15

min• Swim up to 3mph

Other continued

• Swim backwards• Digging weakens dams• Predators: mink, raptors, snapping turtles, fox, and

coyote

References

Jones, J.K, Jr. and E.C. Birney. 1988. Handbook of Mammals of the North-Central States. University of Minnesota Press, Minneapolis

Kays, R.W. and D.E. Wilson. 2002. The Mammals of North America. Princeton University Press, Princeton, New Jersey.

Connecticut Department of Environmental Protection. Available at http://dep.state.ct.us/burnatr/wildlife/factsheets/muskrat.htm

http://www.images.google.com

http://www.nature.ca/notebooks/english/muskrat.htm

Synaptomys cooperiSouthern Bog Lemming

• ID: smaller than voles; similar to Northern species, but with dark brown above & pale gray underside; relatively large head, with small ears concealed by fur; 6 mammae; TL usually 115-140mm

• Distribution: statewide, with possible exception of extreme northwestern IA – Largely abundant in higher

altitudes– When populations are high,

they move to drier habitats

http://www.glfc.forestry.ca/landscape/picgallery_e.html

Synaptomys cooperi• Habitat: variety, including-

clearings in woodlands, grasslands, mixed deciduous/coniferous woodlands, spruce-fir forests and freshwater wetlands– Use runways built by other

mictrotines– Nests built of shredded

vegetation along trails and often built underground

animaldiversity.ummz.umich.edu/.../ view.html

Synaptomys cooperi• Diet: primarily plant material,

leafy parts of sedges, fruits, rootlets, mosses, ferns and bark

• Reproduction: breeding restricted to warmer months; gestation lasts 21-23 days; litter size usually 3-4; newborns pink, except for light gray dorsum

– Development: fur-7 days; lower incisors-6 to 8 days; eyes open-10 to 11 days

– Longevity about 1 year

http://www.dlia.org/atbi/species/animals/vertebrates/mammals/muridael

Synaptomys cooperi• Conservation status: threatened

statewide• Other:

– Even though called “bog” lemming, seldom found near bogs

– Primarily nocturnal & active all year

– Bright green feces in runways signal presence

– Predators include: foxes, coyotes, weasels, badgers, owls, snakes and others

– Parasites include: fleas, mites, ticks and others

http://animaldiversity.ummz.umich.edu/site//resources/mzm2/33.mr2.jpg/view.html

References• Animal Diversity Web. Southern Bog Lemming. Available at

http://animaldiveristy.ummz.edu. October 2004• ENature. Southern Bog Lemming. Available at

http://www.enature.com/search/show_search/South_Bog_Lemming.October 2004

• Iowa Department of Natural Resources. Iowa’s threatened and endangered species. Available at http://www.state.ia.us/dnr/organiza/ppd/tespecies.htm. October 2004

• Jones, J.K, Jr. and E.C. Birney, 1998. Handbook of Mammals of North-central States. University of Minnesota Press, Minneapolis.

• Kays, R.W. and D.E. Wilson. 2002. Then Mammals of North America. Princeton University Press, Princeton, New Jersey