Northern River Otter Skull Replica measures 4.5 inches. Northern River Otter Skull is museum quality Polyurethane cast. 2-part skull (separate cranium & jaw). Made in USA.

The Northern River Otter was identified as a species of otter and has a lot of names, including northern river otter, common otter and river otter. Other documented names are American otter, Canada otter, fish otter, land otter, nearctic river otter, and Prince of Wales otter.

The Northern River Otter is a stocky animal of 11 to 31 lb., with short legs, a muscular neck no smaller than the head, and an elongated body that is broadest at the hips. They have long bodies, and long whiskers that are used to detect prey in dark waters.

An average adult male weighs about 25 lb. and the female’s average is 18 lb. Its body length ranges from 26 to 42 inches. About one-third of the animal’s total length consists of a long, tapered tail. Tail lengths range from 12 to 20 inches.

A broad muzzle is found on the Northern River Otters flat head, and the ears are round and inconspicuous. The nose is bare, with an obtuse, triangular projection. Eyes are small and dark brown.

Most mustelids, including otters, have 36 specialized teeth, including sharp canines and carnassials that inflict lethal bites to prey. Also, North American river otters have large molars used for crushing hard objects, such as the shells of molluscs. Additional premolars may be present.

The range of the Northern River Otter has been significantly reduced by habitat loss, beginning with the European colonization of the Americas. In some regions, though, their population is controlled to allow the trapping and harvesting of otters for their fur.

Northern River Otters are very susceptible to the effects of environmental pollution, which is a likely factor in the continued decline of their numbers. A number of reintroduction projects have been initiated to help halt the reduction in the overall population.

The Northern River Otter are renowned for their sense of play. Otter play mostly consists of wrestling with conspecifics. Chasing is also a common game. North American river otters rely upon play to learn survival skills such as fighting and hunting.

A highly active predator, the North American river otter has adapted to hunting in water, and eats aquatic and semiaquatic animals.

The vulnerability and seasonal availability of prey animals mainly governs its food habits and prey choices.

This availability is influenced by the following factors: detectability and mobility of the prey, habitat availability for the various prey species, environmental factors, such as water depth, temperature, and seasonal changes in prey supply.

For example, a study conducted in a central California marshland indicated crayfish formed nearly 100% of the river otter’s diet at certain times of the year. However, North American river otters, as foragers, will immediately take advantage of other prey when readily obtainable.

Other prey consumed includes fruits, aquatic plants, reptiles, amphibians, birds (most especially moulting ducks which render the birds flightless and thus makes them easier to capture), aquatic insects, small mammals, and mollusks.