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River Otter
Lutra canadensis
by Erika
Classification
Kingdom: Anamalia
Phylum: Chordata
Class: Mammalia
Order: Carnivora
Family: Mustelidae
Genus: Lutra
Species: canadensis
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Physical Description
The Lutra canadensis is a semi-aquatic mammal with
a long body, thick tapered noses, and short legs. They have wide rounded
heads, small ears, and nostrils that are capable of closing when the Lutra
canadensis is submerged under water. If the water they dived in was
a bit murky they could easily find fish with their vibrissae, or whiskers.
The River Otters fur is a dark brown colour, that can almost be a light shade
of black. Their cheeks and under bellies are a lighter shade of brown.
There fur is dense and soft. It insulates them when they are under
water. The Otter has webbed feet with claws. Their body length
ranges from 889 mm to 1300 mm. Tail lengths range from 300 mm to 507
mm. Their weights depend on the gender of the Otter, ranging from 5
kg to 14 kg. Males average larger than females in all measurements.
Diet and Feeding Habits
The River Otter is a carnivore which means an animal that
eats other animals. The Lutra canadensis mostly eats fish,
crustaceans, amphibians, snakes, water insects, snails, worms, small mammals,
birds, eggs, frogs, turtles,and any aquatic invertebrates when they are
in the wild. When the are in captivity they have a little bit
of a different diet. This includes horsemeat with vegetables, minerals,
vitamins, mackerel, and sometimes crayfish. During the winter a River
Otter will move to a place where the water does not form ice, so they can
continue to catch fish. In the Spring and Summertime months they will
move to a new area where they can have a new selection of food, living arrangements,
and companions.
Reproduction
Breeding takes place between the months or March and April. It
than takes 290- 380 days for the baby otters to be born. Since Otters
are mammals they give birth to live young. Up to six otters can be
born in the pregnancy. At birth the pups weigh four to six ounces
and have a length of 8-11 inces long. The pups are blind and helpless
when they are born. Five weeks later they gain eyesight. When
they are two months old they can finally leave the den, eat solid food, and
have their first swimming lesson. They drink their mothers milk until
they are three months old. They are self-sufficent at eight months
but they remain with their family until the next liter of otters arrive.
Otters reach sexual maturity at age 2.
Habitat
Woodland Areas, Rivers, Northern USA, Canada, Mt. Desert Island, and
Rocky Sea Coasts are where the River Otters reside. They can survive
in Southwest America and The Gulf States. Their habitat must have
a huge amount of food that is easy for them to catch, and of course a body
of water that is clean and unpolluted. They inhabit rivers, streams, lakes,
and ponds. They live in dens made of grass, moss, and leaves.
The dens are underground near a body of water, or in a hollowed out tree.
River Otters do not make their own dens, they scavenge abandoned beaver
dens, and remodel them. Arcadia National Park is a perfect place for
these frisky animals to reside with all the natural landscapes, and
all the trees.
Role in the Ecosystem
The River Otter is a carnivore. It is a predator of fish and other
aquatic invertebrates. On occasion they will consume aquatic plants,
and perhaps a bird or two. It’s largest predator is humans.
Water pollution and destruction of habitats are predators too. In
some states the River Otter is protected by state-law, but in others where
they are not protected they are legal to hunt. On average though hunters
admit that they have a hard time catching these intelligent mammals.
Present Status
In Maine there is a stable population, but in other states, River Otters
are becoming less common and have laws that protect them from being hunted.
Interesting Facts
River otters communicate with a varitey of squeals, chirps, chatters,
and other noises.
They enjoy sunning themselves during the day time and hunting during
the night.
The main threats to River Otters are water pollution and habitat destruction.
The Lutra canadensis is found in all of the US other than Hawaii.
A river otter’s tail is 1/3 the animals total lemgth.
There are 1,000 hairs per square inch of fur on a River Otter.
They can hold their breath for up to 8 minutes under water and run at
speeds up to 29 km per hour.
The River Otter can swim 7 mph and dive up to 35 ft.
Otters belong to the Weasel Family.
River Otters lie wrapped in giant seaweed called kelp.
Otters float together in groups called rafts.
Old male otters often have white fur.
The River Otter can hold itself up with its tail.
Otters always wash themselves after a meal.
All otters carry with them a favorite stone.
The Otters use their stone to smash open shells so they can get food.
Females are a third smaller than males.
King James I of England kept a pack of River Otters as pets.
Male otters are called Dogs.
Bibliography
http://animaldiversity.ummz.umich.edu/site/accounts/information/Lontra_canadensis.html
University of Michigan Scholars (2006) Dewey, T. and E. Ellis. 2003.
http://www.twingroves.district96.k12.il.us/wetlands/RiverOtter/ROHabitat.html
Twin Groves Museums in the Classroom Team Created: 27 June1998- Updated:
30 April 2003
www.kritterfacts.com/riverotterfacts1.htm © 2005 RLR Marketing
http://www.luddist.com/otter.htm
http://www.otternet.com/
http://neyture.info/teachered/endanger/reports/mammals/otter~river/otter~river.html#200
Last updated on March 9, 1998
http://www.cmaquarium.org/Mammals/Otters.htm
http://www.bear-tracker.com/otter.html by: Kim A. Cabrera Page updated:
Sunday, February 1, 2003.
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