Castor canadensis
| North American Beaver
(Castor canadensis) | |
|---|---|
| Range | |
 | |
| Taxonomic classification | |
| Order: | Rodentia |
| Suborder: | Supramyomorpha |
| Infraorder: | Castorimorphi |
| Superfamily: | Castoroidea |
| Family: | Castoridae |
| Subfamily: | Castorinae |
| Genus: | Castor |
| Binomial details | |
| Castor canadensis Kuhl, 1820 | |
| Other resources | |
| Full taxonomic details at MDD | |
The North American Beaver (Castor canadensis) is a large-sized rodent well-suited for aquatic life with its paddle-like tail, dense fur, and webbed hind feet.
Description
From Jenkins and Busher (1979): "Color may range from yellowish-brown to black, with reddishbrown being most common. Tail is flattened dorsoventrally, scaled, and relatively hairless. It is black in young animals but becomes lighter with age. The eyes have a nictitating membrane, ears and nose are valvular, and lips close behind incisors. Each limb has five digits. Hind feet are webbed between digits and the second digit of each is split. Front feet are small and all digits are clawed. Underfur is dense and lead-gray in color. Guard hair is long and coarse."
Museum specimens
-
Holotype: USNM 228006. Castor canadensis baileyi. Adult male. Humboldt River, Humboldt County, Nevada. Collected 13 October 1917. Dorsal view of the skin. -
Holotype: USNM 228006. Castor canadensis baileyi. Adult male. Humboldt River, Humboldt County, Nevada. Collected 13 October 1917. Ventral view of the skin.
External measurements
Length measurements are in millimeters (mm) and weight measurements are in grams (g), unless stated otherwise. If available, the sample size (n=) is provided. If a range is not provided and n= is not given, then the listed measurement represents an average.
| Part of range | Reference | Total length | Tail length | Hindfoot length | Ear length | Mass |
|---|---|---|---|---|---|---|
| California | Jameson & Peeters (2004) | 1.0–1.2 m | 260–330 | 150–200 | 23–29 | 11–26 kg |
| Carolinas, Virginia, Maryland | Webster et al. (1985) | 1,020–1,220 | 27 kg | |||
| Colorado | Armstrong et al. (2010) | 850–1,200 | 200–350 | 180–200 | 27–30 | 16–32 kg |
| Nebraska | Johnsgard (2020) | 850–1,000 | 258–325 | 11–35 kg | ||
| North Dakota | Seabloom et al. (2020) | 1,098 | 328 | 182 | 35 | 20–27 kg |
| not reported | Best & Dusi (2014) | 1,000–1,200 | 258–365 | 156–205 | 23–29 | 11–26 kg |
| Oregon (southwestern and south-central) | Verts & Carraway (1998) | 914–1,137 (n=17) | 260–318 (n=17) | 165–278 (n=17) | 30 (n=2) | 17–27 kg |
| Texas | Schmidly & Bradley (2016) | 1,160 mm | 400 | 178 | 18 kg | |
| Virginia | Linzey (1998) | 900–1,200 | 225–300 | 13.5–22.5 kg |
Skull
-
Holotype: USNM 228006. Castor canadensis baileyi. Adult male. Humboldt River, Humboldt County, Nevada. Collected 13 October 1917. Dorsal view of the skull. -
Holotype: USNM 228006. Castor canadensis baileyi. Adult male. Humboldt River, Humboldt County, Nevada. Collected 13 October 1917. Ventral view of the skull. -
Holotype: USNM 228006. Castor canadensis baileyi. Adult male. Humboldt River, Humboldt County, Nevada. Collected 13 October 1917. Lateral view of the skull. -
Holotype: USNM 228006. Castor canadensis baileyi. Adult male. Humboldt River, Humboldt County, Nevada. Collected 13 October 1917. Dorsal view of the mandible. -
Holotype: USNM 228006. Castor canadensis baileyi. Adult male. Humboldt River, Humboldt County, Nevada. Collected 13 October 1917. Lateral view of the left mandible.
References
Armstrong DM, Fitzgerald JP, Meaney CA. 2010. Mammals of Colorado, Second Edition. Denver (CO, USA): University Press of Colorado.
Best TL, Dusi JL. 2014. Mammals of Alabama (Vol. 4). Tuscaloosa (AL, USA): University Alabama Press.
Jameson EW, Peeters HJ. 2004. Mammals of California (No. 66). Berkeley (CA, USA): University of California Press.
Jenkins SH, Busher PE. 1979. Castor canadensis. Mammalian species (120):1-8. https://doi-org.ezproxy1.lib.asu.edu/10.2307/3503787
Johnsgard PA. 2020. Wildlife of Nebraska: a natural history. Lincoln (NE, USA): University of Nebraska Press.
Linzey DW. 1998. The mammals of Virginia. McDonald & Woodward Publishing.
Schmidly DJ, Bradley RD. 2016. The mammals of Texas. Austin (TX, USA): University of Texas Press.
Seabloom R, Hoganson JW, Jensen WF. 2020. The mammals of North Dakota. Fargo (ND, USA): North Dakota State University Press.
Verts BJ, Carraway LN. 1998. Land mammals of Oregon. Berkeley (CA, USA): University of California Press.
Webster WD, Parnell JF, Biggs WC. 1985. Mammals of the Carolinas, Virginia, and Maryland. Chapel Hill (NC, USA): University of North Carolina Press.