Northern Prairie Wildlife Research Center
Keys to North American mammals are available in several works but few are available for specific regions or states. Some of these keys, or parts of them, are difficult to use. I have often had to consult several of them before I could key out a specimen. Most keys use a combination of skin and skull features for separation of species. Frequently, a skin or a skull is all that is available. Thus, one is often frustrated in an attempt to identify a specimen. A skin key to North Dakota mammals is available (Wiehe and Crooke 1976b). With the publication of this skull key I hope to fill a gap and facilitate the further study of mammals in the state. I have attempted to write as uncomplicated a key as I could so that students, amateur naturalists, and professionals can use it.
The species included in this key are considered current North Dakota mammals (Wiehe and Crooke 1976a). I have not included species for which poorly documented or very old records are available (e.g., Star-nosed Mole, Condylura cristata; Merriam's Shrew, Sorex merriami). I have also excluded species which some sources consider as of possible occurrence resulting from ranges that approach the borders of the state (e.g., Water Shrew, Sorex palustris; Southern Flying Squirrel, Glaucomys volans).
In order to help point out the specific characters used in many of the couplets, illustrations (which are not drawn to scale) have been included. These should greatly increase the efficiency of the key; furthermore, they have instructive value. The illustrations were done by J. Frank Cassel. The skull measurements used to construct this key are from adult specimens.
As changes in zoological nomenclature occur frequently, some name changes for mammals are imminent. The scientific and common names of mammals found in this key are the most current and are taken from Jones et al. (1975).
Wiehe, J. M. 1978. Key to the skulls of North Dakota mammals. Prairie Naturalist 10(1):1-16.
This resource should be cited as:
Wiehe, J. M. 1978. Key to the skulls of North Dakota mammals. Prairie Naturalist 10(1):1-16. Jamestown, ND: Northern Prairie Wildlife Research Center Online. http://www.npwrc.usgs.gov/resource/mammals/skulls/index.htm (Version 17NOV2000).