North American River Otter
North American river otters have long, streamline bodies with a rudder-like tail. Their fur color ranges from a milky chocolate brown to an almost blackish brown. They have white to cream colored fur on their bellies. Their skulls are flattened with a short broad muzzle, providing for easy swimming and breathing. Their short ears are also made for life in the water. It has long thick whiskers used for underwater and nighttime sensory. There is slight sexual dimorphism with the males being larger than the females.
The body design of the otter is perfectly suited for the water. They have short, webbed paws that propel them forward. They have a rudder-like tail that allows quick movement and change of direction. They have sharp canines designed to kill prey quickly. They have musk glands, like all other muskalids, which are used to deter predators when frightened. The can also have delayed implantation, to better time the birth of the offspring.
North American river otters are very adept to surviving in various habitats. Their ability of delayed implantation distinguishes them from their European cousins. These otters form small family groups that consist of one mother, juveniles, yearlings, and helpers. The adult males will only stay with a family group until the new pups are born. They have a wide range of vocal capabilities such as barking or chirping. They use these sounds to communicate with individuals of their family groups.