Otter:

Aquatic carnivore found worldwide except in Australia, New Zealand, and Antarctica. In the common species distributed throughout Europe and Asia, the body may attain a length of 75 cm (30 in), with a tail half as long as the body. The head is broad and flat, with short, rounded ears; the blunt snout bears lateral, slit-like nostrils. The ears and nostrils can be closed when the animal is diving. The fur is chestnut, the legs are short but strong, and the webbed feet have claws. A similar species is found in North America.

Otters live in dens, usually by the side of water and with an underwater entrance to the den. They feed on fish and small mammals, birds, frogs, and crayfish. The animals breed in the spring, and authorities have reported a gestation period of about 61 days for the species already mentioned. Certain investigators have also observed delayed implantation in the North American species, with a gestation of almost 12 months. Development still lasts only two months, however, because almost no development occurs between mating and the time when the fertilized eggs are implanted in the uterus. The litters range from one to five pups, which stay with the mother for about a year.

Scientific classification: Otters belong to the family Mustelidae. The otter of Europe and Asia is classified as Lutra lutra. The North American otter is classified as Lutra canadensis.