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Muskrat

Ondatra zibethicus

Summary 3

Ondatra zubethicus may weigh up to four pounds and is sixteen to twenty four inches in length. They have thick fur that is lustrous and black to silvery-brown, as shown in the figure above. The dorsal part of their body is darker than the ventral portions. The throat and ventral portions of their body are lighter in fur color. Its hind legs are somewhat webbed for swimming and it has a long tail that is scaly and hairless. One way to tell the difference between a muskrat and a beaver is the tail of the muskrat is longer and skinnier. It is not as wide as a beaver tail. Additionally, when the muskrat swims, their whole body is exposed, whereas when the beaver swims, only their head is exposed on the surface of the water. Even further, beavers grow much larger than muskrats, and they may weigh up to fifty four more pounds than muskrats. The ears of the muskrat are hidden within the fur and they have large heads with medium sized whiskers. Muskrats are also named after their musky odor which smells very potent.

The scat of the muskrat is dark and may even appear black, as seen in the figure above. The consistency of the scat is semi-liquid. The shape of muskrat scat is sausage-like and sometimes one end is pointy. Contents inside the scat will consist of mostly plant matter.

The tracks of the muskrat are distinct in that the front paws appear to have four toes, but there is another teeny little toe not shown in the figure. The hind feet are narrow and about three inches long. The hind feet are additionally partially webbed and they have claws for digging which are shown in the figure as tiny dots above the toes.

The muskrat cannot be found in Iron County. Ondatra zubethicus, in particular, is distributed throughout the eastern United States and southeastern Canada.

http://animaldiversity.org/site/accounts/information/Ondatra_zibethicus.html
Halfpenny, J. C. (1986). A field guide to mammal tracking in western America. Boulder CO: Johnson Printing Company.
http://www.chesapeakebay.net/field-guide-beta/entry/Muskrat
http://www.fs.fed.us/database/feis/animals/mammal/onzi/all.html#DISTRIBUTION AND OCCURRENCE
https://www.washingtonpost.com/lifestyle/kidspost/beaver-or-muskrat-heres-how-to-tell/2012/05/21/gIQA6ceOgU_story.html

Location and Habitat 4

The muskrat (Ondatra zibethicus), the only species in genus Ondatra and tribe Ondatrini, is a medium-sized semiaquatic rodent native to North America, and introduced in parts of Europe, Asia, and South America. The muskrat is found in wetlands over a wide range of climates and habitats. It has important effects on the ecology of wetlands and is a resource of food and fur for humans. It is an introduced species in some of its present range.

Sources and Credits

  1. (c) Vitaliy Khustochka, some rights reserved (CC BY-NC), http://www.flickr.com/photos/phenolog/4159982548/
  2. (c) josiebrandowriggs, all rights reserved
  3. Adapted by josiebrandowriggs from a work by (c) Wikipedia, some rights reserved (CC BY-SA), http://en.wikipedia.org/wiki/Ondatra_zibethicus
  4. (c) josiebrandowriggs, some rights reserved (CC BY-SA)

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