Otters: Profile and Information

Otters are carnivorous mammals in the Lutrinae subfamily.

The 13 existing otter species are all semiaquatic, aquatic, or coastal, with fish and invertebrate-based diets.

Lutrinae is a section of the family Mustelidae that includes weasels, badgers, mink, and Wolverine, among other species.

Scientific Classification

Terminology

The home of an otter is referred to as a holt or sofa. Male otters are known as dogs or boars, females are referred to as bitches or sows, and their offspring are called pups.

The collective nouns for otters are kin, bevvy, romp, lodge (indicative of their sometimes playful nature), or raft when in water.

The feces of otters are generally recognized by their peculiar scent, which has been identified as varying from freshly mown hay to putrefied fish; these are known as spraints.

Life Cycle

The gestation period is around 60 – 86 days in otters. The bitch, dog, and older offspring cater for the newborn pup.

Bitch otters attain sexual maturity at approximately two years of age and males at roughly three years.

More popular in Scotland, the holt is constructed under tree roots or a rocky cairn. Moss and grass are loaded with it.

The pup can leave the holt after one month and swim after two months. The pup has to live with its parent for around one year before it’s able to fend for itself.

Otters can live up to 16 years; they’re playful by nature and frolic with their pups in the water. Its usual food source is trout, and further downriver, eels, but frogs and birds may be sampled.

Description

Otters have long, slender bodies and limbs that are relatively short. Their most compelling anatomical qualities are the strong webbed feet used to swim and their seal-like abilities to hold breath underwater.

Many have sharp claws on their paws, and they all have long, muscular tails, except the sea otter. In adult size, the 13 species range from 0.6 – 1.8 m (2.0 – 5.9 ft ) in length and from 1 – 45 kg (2.2 – 99.2 lb) in weight.

The tiniest otter species is the Asian small-clawed otter, and the biggest is the giant otter and sea otter. They have a fuzzy, isolated underfur covered by a long guard-hair outer layer. This traps a layer of air, keeping them dry and somewhat buoyant under the water.

Many otter species live and have high metabolic levels to help keep them warm in cold waters. European otters must consume 15 percent of their body weight daily, and sea otters 20 – 25 percent, depending on the weather.

To survive, an otter needs to eat 100 g (3.5 oz) of fish per hour in water as warm as 10 ° C ( 50 ° F). Most animals hunt for 3 – 5 hours daily, and nursing mothers hunt for about 8 hours daily.

Feeding

For most otters, fish is their dietary staple. Frogs, crayfish, and crabs are also added to their diet.

Some otters are shellfish opening specialists, while others will prey on small mammals or available birds. Prey-dependence makes otters very susceptible to the depletion of prey. Sea otters hunt clams, sea urchins, and other shelled creatures.

They are remarkable for their ability to use stones on their bellies to crack open shellfish, and the young must learn this skill. Otters are active hunters, exploring the beds of rivers, lakes, or oceans, pursuing prey in the water.

Most of them live next to the water, but typically, river otters reach it only to hunt or fly, otherwise spending much of their time on land to avoid waterlogging of their fur.  Sea otters are much more aquatic, living in the ocean throughout their lives.

Otters are adventurous creatures and seem to engage in different activities for fun, such as making water slides and falling into the water on them. They can even find small stones and play with them.

Different species differ in their social structure, with some being mostly solitary while others living in groups. These groups may be relatively large in a few species.

Species

European Otter

The European otter (Lutra lutra), or the Eurasian otter, occupies Europe, most of Asia, and parts of North Africa. They were widespread in the British Isles as early as the 1950s.

Nevertheless, they became rare in many regions due to chlorinated hydrocarbon pesticides, habitat loss, and water contamination (relatively widespread in parts of Scotland and Ireland).

In the 1980s, population levels hit a low point but are recovering sharply. The UK Biodiversity Action Plan considered the re-establishment of otters by 2010 in all the UK coastal areas they occupied in 1960.

Roadkill accidents have been one of the biggest challenges to their re-establishment progress.

North American River Otter

The North American river otter (Lontra Canadensis) became among the main animals hunted and captured in North America for fur after contact with Europeans.

An assortment of fish, shellfish, small land mammals, and birds are eaten by river otters. They grow to a length of one meter (3 – 4 ft) and weigh from 10 – 30 lb (5 – 15 kilograms).

This is a protected species in some countries, and some places have otter sanctuaries that aid the rehabilitation of sick and wounded otters.

Sea otter

Sea otters are known as marine mammals (Enhydra lutris) and live along North America’s Pacific coast. The Bering Strait and Kamchatka shallow waters, as far south as Japan, were part of their native habitat.

There are about 26,000 – 165,000 hairs per square centimeter of skin in sea otters, a rich fur for which humans nearly hunted them to extinction.

At the time when the 1911 Fur Seal Treaty granted them protection, only a few sea otters existed when the fur trade had become financially unviable. Sea otters consume shellfish and other invertebrates (especially clams, abalone, and sea urchins).

The density of prey otters hunt affects their populations. Since the otter food supply is easier to excavate from rocky-bottom habitats, more otters prefer to live in waters with rocky bottoms, having access to shallow-burrowing prey, as opposed to soft-bottom habitats.

They also carry a rock under their forearm in a pocket and use it to break open shells, making them one of the relatively limited number of animals using instruments.

They grow to a length of 1.0 – 1.5 m (3.3 – 4.9 ft) and weigh 30 kg (66 lb). They were once near extinction but have begun to extend their reach from remnant populations in California and Alaska.

Unlike most marine mammals (such as seals or whales), sea otters don’t have a layer of insulating fat.

They depend on the layer of air trapped in their fur, as with other species of otters, which they keep on top by blowing from their mouths into the fur. Most of their time is spent in the sea, while other otters spend much of their time on land.

Giant Otter

The giant otter (Pteronura brasiliensis) inhabits South America, especially the Amazon River basin. Nonetheless, it is becoming scarce because of poaching, habitat destruction, and the use of mercury and other contaminants in illegal alluvial gold mining.

This gregarious species grows up to 1.8 m (5.9 ft ) in length and is more aquatic than most other otters.

Frequently Asked Questions