- What’s in a name? This “musky-odored” rodent uses two musk glands at the base of the tail to communicate with others of its kind. Muskrats (Ondatra zibethicus) will liberally cover strategic lodging areas with their musky scent, either to intimidate intruders such as the neighborhood weasel, or to advertise the female’s presence and availability. Both sexes have the musk glands.
- The muskrat is of the family Cricetidae and is the largest member of the North American “New World” mice. Frequently thought of as a relative of the beaver, it is actually a closer relative to voles, lemmings and deer mice.
Click on the language to view common names.
Common Names in English:
Common Names in French:
Rat Musqu, rat musquÃ©, rat musqué
Species Ondatra zibethicus
The muskrat has some interesting physical adaptations that enable it to occupy the watery niche of wetlands and riparian areas. This small three pound aquatic rodent can stay beneath the water’s surface for up to 17 minutes! One might think a muskrat is soaked to the skin . Not so! Its waterproof underhair lies above an insulating layer of air , so water never touches the skin. As an added benefit, the layer of air keeps the animal buoyant . Muskrat is a durable and widely used fur. It sometimes goes by the more glamorous name of “Hudson Seal” fur. The muskrat smells and hears superbly but sees poorly. Its hind feet are almost twice the size of its front, webbed feet. There are five toes with very long nails, although the fifth toe on the front foot is so small it does not register in a track. The hind foot has stiff hairs surrounding the toes to help support the animal in soft mud and aids in swimming as well. Active all year, muskrat tracks and tail drag marks can be found in snow. Muskrat scat can be found on rocks and logs above the waterline. The scat is composed of little pellets stuck together, although sometimes the pellets are separate.
Typically found in a lake at a mean distance from sea level of 451 meters (1,478 feet).
Muskrats are found in brackish
and fresh-water lakes
, and marshes. Depending on the location, they will either
dig burrows into waterside
banks, or construct houses of vegitation.
Houses are built so that the main chambers are above water level,
but can only be entered through underwater tunnels. Separate structures
are constructed for feeding and nesting (Feldhamer, 1999 in Wilson
and Ruff, 1999). Muskrats exhibit
many morphological adaptations
life, including lips
that close behind
incisors to allow
gnawing under water, partially webbed
hindfeet, and the ability to
submerged for up to 20 minutes. Muskrats are primarily herbivorous,
feeding on aquatic vegiation such as cattails and horsetails. During
periods of food scarcity, individuals will also consume animal matter
such as mussels, turtles, mice, birds, frogs
and fish (Wilner et
List of Habitats :
- 5 Wetlands (inland)
- 5.1 Wetlands (inland) - Permanent Rivers/Streams/Creeks (includes waterfalls )
- 5.4 Wetlands (inland) - Bogs , Marshes, Swamps , Fens , Peatlands
- 5.5 Wetlands (inland) - Permanent Freshwater Lakes (over 8ha)
- 5.7 Wetlands (inland) - Permanent Freshwater Marshes/Pools (under 8ha)
- 5.14 Wetlands (inland) - Permanent Saline, Brackish or Alkaline Lakes
- 5.16 Wetlands (inland) - Permanent Saline, Brackish or Alkaline Marshes/Pools
- 15 Artificial/Aquatic & Marine
- 15.1 Artificial/Aquatic - Water Storage Areas (over 8ha)
- 15.2 Artificial/Aquatic - Ponds (below 8ha) [more info]
Several muskrats may share a lodge and together increase the temperature inside a lodge to as much as 20 degrees C above outside temperature. The construction of lodges occurs from late August until late October. Building on a platform of mud , the muskrat uses small aquatic plants such as cattails, sedges, weeds , leaves, sticks and more mud until the structure is about 2 feet high. Then the muskrat excavates from inside and hollows out an area to fit a family . This interior is usually 3 ft . to 5 ft in diameter with wall thickness from 3 inches to 12 inches. In this “muskrat rooming house” each family member may construct its own sleeping quarters. There will typically be one to two plunge holes leading to tunnels that connect the lodge to the open water .
- Whittaker & Margulis,1978
- Linnaeus, 1758
- (Hatschek, 1888) Cavalier-Smith, 1983
- Grobben, 1908
- (Haeckel, 1874) Cavalier-Smith, 1998
- Bateson, 1885
- Cuvier, 1812
- Jawed Vertebrates
- Goodrich, 1930
- (Rowe, 1988) Mckenna & Bell, 1997:vii,36
- (Wible Et Al., 1995) Mckenna & Bell, 1997:vii,43
- Mckenna, 1975
- Mckenna, 1975
- Mckenna, 1975
- (Mckenna, 1975) Mckenna & Bell, 1997:vii,48
- (Parker & Haswell, 1897) Mckenna & Bell, 1997:viii,49
- (Owen, 1837) Mckenna & Bell, 1997:viii,80
- (Mckenna, 1975) M.c. Mckenna & S.k. Bell, 1997
- (Mckenna, 1975) Mckenna in Stucky & Mckenna in Benton, Ed., 1993:7
- (Szalay & Mckenna, 1971) Mckenna, 1975:41
- (Weber, 1904) Mckenna & Bell, 1997:viii, 113
- Series: http://www.biodiversitylibrary.org/title/58046" ta ()
- Order: Rodentia () - Rodents
- Mirorder: Simplicidentata () - (Weber, 1904) Mckenna & Bell, 1997:viii, 113
- Grandorder: Anagalida () - (Szalay & Mckenna, 1971) Mckenna, 1975:41
- Superorder: Preptotheria () - (Mckenna, 1975) Mckenna in Stucky & Mckenna in Benton, Ed., 1993:7
- Magnorder: Epitheria () - (Mckenna, 1975) M.c. Mckenna & S.k. Bell, 1997
- Cohort: Placentalia () - (Owen, 1837) Mckenna & Bell, 1997:viii,80
- Supercohort: Theria () - (Parker & Haswell, 1897) Mckenna & Bell, 1997:viii,49
- Infralegion: Tribosphenida () - (Mckenna, 1975) Mckenna & Bell, 1997:vii,48
- Sublegion: Zatheria () - Mckenna, 1975
- Legion: Cladotheria () - Mckenna, 1975
- Superlegion: Trechnotheria () - Mckenna, 1975
- Infraclass: Holotheria () - (Wible Et Al., 1995) Mckenna & Bell, 1997:vii,43
- Subclass: Theriiformes () - (Rowe, 1988) Mckenna & Bell, 1997:vii,36
- Class: Mammalia ()
- Superclass: Tetrapoda () - Goodrich, 1930
- Infraphylum: Gnathostomata () - Auct. - Jawed Vertebrates
- Subphylum: Vertebrata () - Cuvier, 1812 - Vertebrates
- Phylum: Chordata () - Bateson, 1885 - Chordates
- Infrakingdom: Chordonia () - (Haeckel, 1874) Cavalier-Smith, 1998
- Branch: Deuterostomia () - Grobben, 1908
- Subkingdom: Bilateria () - (Hatschek, 1888) Cavalier-Smith, 1983
- Kingdom: Animalia () - Linnaeus, 1758 - animals
Castor zibethicus • Castor zibethicus Linnaeus • Ondatra americana Tiedemann
Status: Accepted Name
Last scrutiny: 09-Jun-2004
Members of the genus Ondatra
ZipcodeZoo has pages for 4 species and subspecies in this genus:
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Accessed through GBIF Data Portal November 26, 2007:
- Louisiana State University Museum of Natural Science, Mammal specimens
- Mammal Research Institute PAS, Mammal Collection
- Marine Science Institute, UCSB, Paleobiology Database
- Michigan State University Museum, Vertebrate specimens
- Museum of Texas Tech University
- , Mammal specimens
- Museum of Vertebrate Zoology, Terrestrial vertebrate specimens
- Royal Ontario Museum, Mammal specimens
- Sternberg Museum of Natural History, Mammal Collection
- UK National Biodiversity Network, Biological Records Centre - Mammal records from Britain from the Atlas of Mammals
- , with some subsequent records
- UNIBIO, IBUNAM, CNMA/Coleccion Nacional de Mamiferos
- University of Alaska Museum of the North, University of Alaska Museum Mammal Collection
- University of Alaska Museum of the North, University of New Mexico Museum of Southwestern Biology Mammal Collection
- Biodiversity Heritage Library NamebankID: 108006
- Catalogue of Life Accepted Name Code: ITS-552810
- Global Biodiversity Information Facility Taxonkey: 4490920
- Integrated Taxonomic Information System (ITIS) Taxonomic Serial Number (TSN): 180318
- IUCN ID: 228082
- Natural Heritage Network Species Identifier: AMAFF15010
- Zipcode Zoo Species Identifier: 178844
- New Mexico Wildlife. New Mexico Department of Game and Fish Version of April 24, 2009. [back]
- Standard Deviation = 638.060 based on 1,357 observations. Altitude information for each observation from British Oceanographic Data Centre. [back]
- Linzey, A.V. 2008. Ondatra zibethicus. In: IUCN 2011. IUCN Red List of Threatened Species. Version 2011.2. <www.iucnredlist.org>. Downloaded on 03 February 2012. [back]