North American River Otter

North American River Otter

Northern river otter, Common otter, River otter

Kingdom
Phylum
Subphylum
Class
Order
Suborder
Family
Subfamily
Genus
SPECIES
Lontra canadensis
Population size
100,000
Life Span
14-25 years
Top speed
29
18
km/hmph
km/h mph 
Weight
6-9
13.2-19.8
kglbs
kg lbs 
Length
66-110
26-43.3
cminch
cm inch 

The North American river otter (Lontra canadensis) is a semiaquatic mammal that lives along its waterways and coasts. It is the only river otter that is found north of Mexico. These animals live in burrows and like most predators, prey upon the most readily accessible species. They suffer greatly from habitat loss and are often captured for their fur. In the wild, they live only for 8-13 years but in captivity, their life expectancy can reach up to 25 years.

Cr

Crepuscular

Ca

Carnivore

Pi

Piscivores

Se

Semiaquatic

Al

Altricial

Pr

Predator

Na

Natatorial

Te

Terrestrial

Te

Territorial

Vi

Viviparous

Bu

Burrowing

Am

Ambush predator

Po

Polygyny

So

Social

No

Not a migrant

Hi

Hibernating

N

starts with

Appearance

North American river otters have long whiskers that are used to detect prey in dark waters. They differ from the Eurasian otter by their longer necks, narrower visages, smaller space between the ears, and shorter tails. North American river otters have a transparent inner eyelid (called a nictitating membrane) to protect their eyes while swimming. Their fur ranges in color from white and gray to brown and black; it is very thick and water-repellent. Males and female river otters look alike but males are usually larger in size.

Video

Climate zones

North American River Otter habitat map
North American River Otter
Public Domain Dedication (CC0)

Habits and Lifestyle

For the majority of the year, this animal is most active during the period from dusk until dawn, but in winter, it may more commonly be seen during the day. This species’ social structure is very variable, as some animals are solitary, while others live in family groups of an adult female with her offspring, or sometimes in large groups of just adult males. Groups typically travel and hunt together, and also use the same resting site and den. Dens are created in riverside burrows, under vegetation or rocks near the water, in undercut banks or hollow trees, and sometimes in muskrat or beaver lodges. There is much overlap of individual home ranges, and though this animal is non-territorial, it uses scent-marking as an important means of communication. A range of vocalizations is also used to communicate, the most common sound amongst a group being a low-frequency noise that sounds like chuckling, while loud snorts are often used for signaling potential danger.

Seasonal behavior

Diet and Nutrition

The North American river otters are carnivores, they eat mainly aquatic animals such as amphibians, turtles, fish, crayfish, crabs, and other species of invertebrates. Birds and birds’ eggs, as well as small terrestrial mammals, may also be eaten. Sometimes they eat aquatic plants.

Mating Habits

MATING BEHAVIOR
REPRODUCTION SEASON
December-April
PREGNANCY DURATION
2 months
BABY CARRYING
1-6 pups
INDEPENDENT AGE
3 months
FEMALE NAME
female
MALE NAME
male
BABY NAME
whelp, pup

North American otters are polygynous, with males often breeding with several females, probably ones whose home ranges overlap theirs. Breeding is from December to April: late winter or early spring. Gestation is for 2 months, but young may be produced up to a year after breeding due to delayed implantation. Births take place from November to May, peaking in March and April. A female gives birth to 1 to 6 young in each litter, averaging 2 to 3. The otters have fur when they are born, but are otherwise helpless. Birthing and the raising of young takes place in a den near water. Pups will open their eyes when they are one month old and are weaned when about 3 months old, starting to leave their birth range from 6 months to the age of one year. They reach reproductive maturity at the age of 2 to 3 years.

Population

Population threats

River otters eat fish, and fish populations are threatened by climate change from rising sea levels. If fish numbers start to decrease or they move elsewhere as a result of climate change, this species would lose its major food source. They are also threatened by the destruction of their habitat. Human contact is influencing this otter’s aquatic habitats. Water quality is lowered, water is depleted, and timber and other vegetation are cleared and become scarce. Most of these problems are due to water pollution. Historically, these animals were hunted for their coats. There is no significant threat today from commercial harvesting, but illegal hunting can affect local populations.

Population number

The Defenders of Wildlife resource, based on harvest reports, estimates the North American otter’s total population size to be over 100,000 individuals. Currently, this species is classified as Least Concern (LC) on the IUCN Red List, and its numbers today remain stable.

Ecological niche

North American river otters are important predators of fish and aquatic invertebrates.

Fun Facts for Kids

  • North American otters are playful animals, and indulge in water play, mud/snow sliding, and burrowing through snow. Many "play" activities serve a purpose, such as strengthening social bonds, practicing hunting techniques, and scent marking.
  • These animals have boundless energy due to their very high metabolism. This means that they have to eat a lot during the day.
  • These otters are very good swimmers and divers, and are able to stay underwater as long as 8 minutes.
  • Otters have the thickest fur of any mammal, having as many as 850,000 hairs per square inch.
  • Mothers will catch and release prey to teach their young how to forage and to catch food items.
  • North American otters are able to dive as deep as 60 feet.
  • Northern American otters are able to close their nostrils in order to keep water out when diving for a long time.

Coloring Pages

References

1. North American River Otter Wikipedia article - https://en.wikipedia.org/wiki/North_American_river_otter
2. North American River Otter on The IUCN Red List site - http://www.iucnredlist.org/details/12302/0

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