Order Rodentia Family Geomyidae Diastema 1 pair incisors Ears shorter than tail External fur-lined pouches Tail less than ¾ length of head, body Hind feet smaller than forefeet Geomys bursarius

Order Rodentia Family Heteromyidae Diastema 1 pair incisors Ears shorter than tail External fur-lined pouches Tail more than ¾ length of head, body Hind feet larger than forefeet Perognathus flavescens

Perognathus flavescens Identification: Dorsum cinnamon with blackish hairs; venter lighter; light-colored patch behind ears and around eyes Distribution: West (Loess Hills), southeast, central Iowa Habitat: Grassy slopes; well drained; small burrows

Perognathus flavescens Diet: Seeds of grasses, other herbs Reproduction: 2-3 litters of 3-8 annually Conservation: Endangered; several isolated populations

Order Rodentia Family Castoridae Diastema 1 pair incisors Ears shorter than tail Hind feet webbed Tail scaly, paddle-shaped Castor canadensis

Castor canadensis Common name: Beaver Order Rodentia Family Castoridae Genus Castor Species Castor canadensis http://www.inhs.uiuc.edu/dnr/fur/species/beaver.html Presented by Catherine Luria

Identification Largest rodent in Iowa Castor canadensis Identification Largest rodent in Iowa TL 94-120 cm; tail, 23-37 cm; hind foot, 17-19 cm; ear, 30-35 mm Usually weighs 15-30 kg, up to 45 kg http://www.inhs.uiuc.edu/dnr/fur/species/beaver.html

Castor canadensis Distribution Much of North America from central Alaska and Northern Canada to Northern Mexico Found throughout Iowa and north-central United States http://www.huntington.edu/thornhill/images/wildlifephotos/beaver.jpg

Habitat Streams, rivers, marshes, and lakes Castor canadensis Habitat Streams, rivers, marshes, and lakes Often near willow, aspen, and other preferred food sources http://www.huntington.edu/thornhill/images/wildlifephotos/beaver.jpg

Castor canadensis Diet Summer: grasses, leaves, roots of aquatic plants, bark stripped from building materials, sometimes berries Winter: leaves and inner bark of stored saplings and branches Prefers willow, aspen, cottonwood, alder; tends to avoid pine except for building www.wildflorida.org/ critters/beaver.asp

Castor canadensis Diet Stores food for winter by anchoring branches and saplings to bottom of pool “Feed pile” is 3-6 feet deep and up to 30-40 feet wide Beaver leaves den through underwater entrance, gets food from the pile, and returns to the den www.occdsb.on.ca/ ~sel/rideau/beaver.htm

Reproduction Breeding starts in January of February Castor canadensis Reproduction Breeding starts in January of February Female bears 1-6 kits (usually 3-4) in April, May, or June Young are weaned in 6 weeks but will stay with family group 1-2 years

Reproduction Family groups consist of around 12 beavers Castor canadensis Reproduction Family groups consist of around 12 beavers One or more pairs of adults Young of that year Yearlings Yearlings leave or are driven off as kits mature

Conservation Status Valuable pelt Castor canadensis Conservation Status Valuable pelt Once trapped to extinction in some areas Protective legislation and natural emigration have allowed beaver to reoccupy much of its former range Now fairly common, even considered a pest in some areas http://www.wildernessclassroom.com/www/schoolhouse/boreal_library/animals/photos/beaver.jpg

Disease Can carry rabies Carries tularemaia Bacterial infection Castor canadensis Disease Can carry rabies Carries tularemaia Bacterial infection Transmitted to humans through contact with beaver tissue or blood or through contaminated water Causes headache, fever, chills, vomiting, aches and pains http://www.wildernessclassroom.com/www/schoolhouse/boreal_library/animals/photos/beaver.jpg

Castor canadensis Dam building Dams constructed of branches, rocks, leaves, and other debris and filled with mud from the stream bottom 4-7 feet across Added to as water level rises Smaller dams are sometimes constructed to relieve pressure on main dam http://www.exzooberance.com/virtual%20zoo/they%20swim/beaver/Beaver%20485050.jpg

Why do beavers build dams? Castor canadensis Why do beavers build dams? Increases the depth and surface area of the stream or pond Easier to drag branches, etc. Prevents the underwater entrance to the den or lodge from freezing over Protects against predation Allows greater access to food http://www.bfro.net/avevid/nelson/images/beaver%20dam.jpg

Castor canadensis Beaver Lodges Built against the back of the den or against the stream bank Dome-like structure built of sticks and mud Underwater entrance(s) http://www.saskschools.ca/~gregory/animals/images/bvr2.jpg

Other Primarily nocturnal/crepuscular Castor canadensis Other Primarily nocturnal/crepuscular Presence easily detected by chewed saplings Little predation: mink take young and large carnivores may attack adults

References Illinois Department of Natural Resources. Ecology and Conservation of Illinois’ Fur Resources. http://www.inhs.uiuc.edu/dnr/fur/index.html Iowa Association of Naturalists. Iowa Mammals. http://www.extension.iastate.edu/publications/ian601.pdf Jones, J. Knox, Jr. and Elmer C. Birney. 1988. Handbook of Mammals of the North-Central States. University of Minnesota Press, Minneapolis. Kays, Roland W. and Don E. Wilson. 2002. Mammals of North America. Princeton University Press, Princeton, NJ.