, is a medium-sized semi-aquatic rodent
native to North
, and introduced in parts of Europe
, and South America
. The muskrat is found in
and is a very successful animal
over a wide range of climates
. It plays an important role in nature
and is a resource of food
, as well
as being an introduced species
much of its present range.
The muskrat is the largest species in the subfamily Arvicolinae
; which includes 142 other species of
rodents, mostly voles
. Muskrats are called "rats
" in a general sense because they are medium-sized
rodents with an adaptable
diet. They are not, however,
so-called "true rats", that is members of the genus Rattus
The muskrat's name comes from the two scent glands
which are found near its tail; they give off a
strong "musky" odor which the muskrat uses to mark its
An archaic name in English for the animal is
, derived from the Abenaki
native word mòskwas
An adult muskrat is about 40 to 60 cm (16 to 24 inches) long,
almost half of that tail
, and weighs from 0.7
to 1.8 kg (1.5 to 4 lb). That is about four times the weight
of the brown rat
), though an adult muskrat is only slightly longer.
Muskrats are much smaller than beavers
), with whom they often share their
habitat. Adult beavers weigh from 14 to 40 kg (30 to 88 lb).
introduced to North America from South America in the early
twentieth century. It shares the muskrat's habitat but is larger, 5
to 10 kg (11 to 22 lb) and its tail is round, not flattened.
It cannot endure as cold a climate as can the muskrat and beaver,
and so has spread only in the southern part of their ranges in
Muskrats are covered with short, thick fur
is medium to dark brown in color with the belly a bit lighter. The
fur has two layers, which helps protect them from the cold water.
They have long tails which are covered with scales rather than hair
and are flattened vertically to aid them in swimming. When they
walk on land the tail drags on the ground, which makes their tracks
easy to recognize.
A Muskrat skull
Muskrats spend much of their time in the water and are well suited
for their semi-aquatic life, both in and out of water. Muskrats can
swim under water for 12-17 minutes. Their bodies, like those of
less sensitive to the build up of carbon
than those of most other mammals. They can close off
their ears to keep the water out. Their hind feet are semi-webbed,
although in swimming the tail is their main means of
propulsion.While most muskrats have brown fur, some with reddish
brown, the black muskrat exists in New Jersey and Virginia. The fur
is nearly black with light gray under belly. Most of these muskrats
exist in marshes near salt water , although some have been trapped
in fresh water lakes.
Distribution and Habitat
are found over most of Canada and the
States and a small part of northern Mexico.
mostly inhabit wetlands
, areas in or near
salt and fresh-water marshlands
, or ponds
. They are not found in the state of Florida where
the round-tailed muskrat, or Florida water rat, (Neofiber alleni
) takes their
Muskrats continue to thrive in most of their native habitat and in
areas where they have been introduced. While much wetland habitat
has been eliminated due to human activity, new muskrat habitat has
been created by the construction of canals
channels and the muskrat
remains common and widespread. They are able to live alongside
streams which contain the sulfurous
that drains away from coal
mines. Fish and
frogs perish in such streams, yet muskrats may thrive and occupy
the wetlands. Muskrats also benefit from human persecution of some
of their predators.
Muskrats normally live in family groups consisting of a male and
female pair and their young, they tend to have 14 young. During the
spring they often fight with other muskrats over territory and
potential mates. Many are injured or killed in these fights.
Muskrat families build nests to protect themselves and the young
from cold and predators.In streams, ponds or lakes, muskrats burrow
into the bank with an underwater entrance. These entrances are 6 to
8 inches wide. In marshes, lodges are constructed from vegetation
and mud. These lodges are up to three feet high. In snowy areas
they keep the openings to their lodges open by plugging them with
vegetation which they replace every day. Some muskrat lodges are
swept away in spring floods and have to be replaced each year.
Muskrats also build feeding platforms in wetlands. It is common to
find muskrats living in lodges, too. Muskrats help maintain open
areas in marshes, which helps to provide habitat for aquatic birds
A muskrat lodge
Muskrats are most active at night or near dawn and dusk. They feed
and other aquatic vegetation.
They do not store food for the winter, but sometimes eat the
insides of their lodges. While Muskrats may appear to steal food
that beavers have stored, more seemingly cooperative partnerships
with beavers exist, as featured in the BBC
documentary The Life of
.Plant materials make up about 95 percent of their
diets, but they also eat small animals such as freshwater mussels
, and small
. Muskrats follow trails that they
make in swamps and ponds. When the water freezes, muskrats continue
to follow their trails under the ice. This is how trappers catch
muskrats in the winter.
Muskrats provide an important food resource for many other animals
, and large owls
, snapping turtles
, and large fish such
prey on baby muskrats. Caribou
sometimes feed on
the vegetation which makes up muskrat lodges during the winter when
other food is scarce for them.
Muskrats, like most rodents, are prolific breeders. Females can
have 2 to 3 litters a year of 6 to 8 young each. The babies are
born small and hairless and weigh only about 22 grams (0.8 oz). In
southern environments young muskrats mature in 6 months, while in
colder northern environments it takes about a year. Muskrat
populations appear to go through a regular pattern of rise and
dramatic decline spread over a 6 to 10 year period. Some other
rodents, including famously the muskrat's close relatives the
lemmings, go through the same type of population changes
History and use by humans
have long considered the muskrat to be a very
important animal. In several Native American creation myths
it is the muskrat who dives to
the bottom of the primordial sea to bring up the mud from which the
earth is created, after other animals had failed in the task.
Muskrats have sometimes been a food resource for humans. Muskrat
meat is said to taste like rabbit
. In the Roman
Catholic Archdiocese of Detroit, there is a
longstanding dispensation allowing
Catholics to consume muskrat on Ash
Wednesday and the Fridays of Lent (when the
eating of meat, except for fish, is prohibited): because the
muskrat lives in water, it is considered equivalent to
Lenten dinners serving muskrat are traditional in parts of
Michigan. The meat is occasionally consumed in Belgium and The
Netherlands, and is traditional dish on the Delmarva
Peninsula and in certain other areas and population segments
of the United States.
fur is very warm and of good quality, and the trapping of muskrats
for their fur became an important industry in the early Twentieth
Century, especially in the state of Louisiana.
Muskrat fur becomes prime at the beginning
of December in most northern states. At that time muskrats were
introduced to Europe
as a fur resource.
Muskrat fur was specially trimmed and dyed and called "hudson seal"
fur, and sold widely in the United States in the early twentieth
century. They spread throughout northern Europe and Asia
. Some European countries such as Belgium and the
Netherlands consider the muskrat to be a pest that must be
exterminated. Therefore the animal is trapped and hunted to keep
the population down. The muskrat is considered a pest because its
burrowing causes damage to the dikes and levees
that these low-lying countries depend on for
protection from flooding. Muskrats also sometimes eat corn
and other farm and garden crops.
- Caras, R. 1967. North American Mammals. New York:
Galahad Books. ISBN 088365072X
- Nowak, R. & Paradiso, J. 1983. Walker's Mammals of the
World. Baltimore, Maryland: The John Hopkins University Press.
- Voelker, W. 1986. The Natural History of Living
Mammals. Medford, New Jersey: Plexus Publishing, Inc. ISBN
- Attenborough, D. 2002. The Life of Mammals. Princeton,
New Jersey: Princeton University Press. ISBN 0691113246
- Attenborough, David. 2002. The Life of Mammals,
Episode 4. BBC Video. 
- McMaster University. 2007 The Muskrat Accessed November 11, 2007.
- Musgrave, P. 2007. "How the Muskrat Created the World" Muskrat.com
- Lukowski, K. 2007. "Muskrat love? It's a Lent thing for downriver
area" The Official Web Site for the Archdiocese of Detroit.
- Ciardi, J. 1983. On Words. Weekly broadcast on