You Otter Know! Trivia Quiz

Answer: 5

River otters have five toes on each foot, just like humans do. These toes are webbed, which helps them swim efficiently through water. Their front feet are smaller and more dexterous, useful for grasping prey. Their back feet are larger and powerful, useful for propulsion on land and in water. Each toe ends in a non-retractable claw. River otters leave distinctive five-toed tracks in mud or snow, which can help wildlife trackers identify their presence.

The presence of five toes on each foot is a trait shared by many mammals, including humans and other primates, reflecting a common evolutionary ancestry or a biological necessity.

Answer: How to swim

River otter pups are taught to begin swimming at around two months old, but they absolutely do not take to the water instinctively. Instead, their mothers teach them, sometimes quite forcefully, by nudging, dragging, or even pushing them into the water. Ker-splash! This seemingly-harsh method is essential for survival, as swimming is a necessary and vital skill for hunting, escaping predators, and exploring their watery habitat.

While, at first, pups may resist or flail, with practice and maternal guidance, they quickly become confident swimmers.

Answer: Delayed implantation

Delayed implantation, also known as embryonic diapause, is a fascinating reproductive strategy used by river otters and several other mammals. After mating, usually between February and April, the fertilized egg does not immediately implant in the uterine wall.

Instead, it remains inside the female in a dormant state for up to ten or even eleven months. This means that although mating happens in early spring, actual gestation doesn't begin until winter, lasting around 60-63 days. The pups are born in the Spring, where conditions are optimal for their survival.

Answer: Red fox

North American river otters are medium-sized mammals with a body length of 66-107 cm (26-42 in) and a tail length of 30-50 cm (12-20 in). They typically weigh 5-14 kg (11-31 lbs), with males being larger than females. Their long, sleek bodies and muscular tails help them swim gracefully, while they are fully adapted to swimming in cold water.

Despite their awesome aquatic affinity, they can move quite quickly on land, too. Their size makes them roughly comparable to a red fox, raccoon, or a Maine Coon cat.

Their bodies are flexible and streamlined for life in rivers, lakes, and wetlands.

Answer: Fish

Fish make up the bulk of the food intake of a river otter, often over 70%, depending on availability and region. River otters prefer slower, easier-to-catch fish like catfish, perch, suckers, and minnows, but will also eat faster prey when they have the energy (or perhaps they have a craving).

When fish are scarce, they supplement their diet with amphibians, freshwater crustaceans, insects, small mammals, birds, and even turtles, or even eggs, if they can find them. While their diet is opportunistic, fish remain their primary and most consistent food source due to abundance and high protein content.

Answer: 8-9 years

River otters typically live 8 to 9 years in the wild, though some may reach 12 years if conditions are ideal. In captivity, where threats are reduced and veterinary care is available, they can live around 25 years or more. In the wild, they are faced with the constant struggle to find food and shelter, have accidents (mostly due to humans), get hunted, and have to deal with pollution. River otters in the wild also need to be on the lookout for predators.

Some of the more common animals that hunt river otters include coyotes, bobcats, alligators and birds of prey.

Answer: Viscachas

River otters belong to the Mustelidae family, a diverse group of carnivorous mammals known for being elongated, agile, and, quite often, fierce hunters. Being a mustelid means river otters are closely related to animals that share similar physical features like long bodies, shorter legs, scent glands, and sharp teeth. They also have similar behavioural features, such as cleverness, curiosity, and strong territorial instincts. Some other animals closely related to them include, mink, weasels, skunks, polecats, ferrets, wolverines, badgers, and martens.

A viscacha is a sad-looking rodent similar to a rabbit, and the subject of many recent memes.

Answer: On land

On land, river otters can run up to 29 km/h (18 mph) in short bursts of speed, which is especially helpful in evading predators. In the water, on the other hand, while otters are playful, agile, and graceful, they don't swim nearly as fast. They have a top swimming speed of 11 km/h (7 mph) but their bodies, with their powerful tails and webbed feet, are very agile while submerged.

They are good, also, at holding their breath. They've been observed diving to depths of 18 meters (30 feet), while holding their breath for four minutes at a time.

Answer: Thick fur that's very dense

River otters are very well-equipped for cold environments, thanks to their incredibly thick fur. It is among the densest in the animal kingdom and reaches up to 26,000 hairs per square centimeter. This double-layered coat consists of a soft, insulating underfur and longer, water-repellent guard hairs that trap air close to the skin (like a scuba dry-suit), keeping them dry and warm even in icy waters.

This thick coat helps even in the winter months both on the ground and in the water, meaning that otters don't have to hibernate.

Answer: Beaver

An otter's home is also known as a holt. River otters rarely build their own; instead, they often take over abandoned lodges made by beavers. Beavers create sturdy structures with underwater dens. These have multiple entrances which providing excellent shelter and protection.

Otters may also use hollow trees, muskrat burrows, and natural crevices along riverbanks. These shelters use the existing infrastructure to offer safety for resting, raising pups, and escaping predators, allowing otters to focus more energy on hunting and playing rather than construction.