Otter is a common name for a carnivorous mammal in subfamily Lutrinae. The 13 extant otter species are all semiaquatic, aquatic or marine, with diets based on fish and invertebrates. Lutrinae is a branch of the weasel family Mustelidae, which also includes weasels, martens, minks, polecats, Eurasian and American badgers, honey badgers and wolverines.
An otter’s den is called a holt or couch. Male otters are called dogs, females are called bitches, and their offspring are called pups. The collective nouns for otters are bevy, family, lodge, romp (being descriptive of their often playful nature) or, when in water, raft.
The feces of otters are typically identified by their distinctive aroma, the smell of which has been described as ranging from freshly mown hay to putrefied fish; these are known as spraint.
The gestation period in otters is about 60 to 86 days. The newborn pup is cared for by the mother, father and older offspring. Female otters reach sexual maturity at approximately two years of age and males at approximately three years. After one month, the pup can leave the holt and after two months, it is able to swim. The pup lives with its family for approximately one year. Otters live up to 16 years.
Otters have long, slim bodies and relatively short limbs with webbed paws. Most have sharp claws on their feet and all except the sea otter have long, muscular tails. The 13 species range in adult size from 0.6 to 1.8 m (2.0 to 5.9 ft) in length and 1 to 45 kg (2.2 to 99.2 lb) in weight. The Oriental small-clawed otter is the smallest otter species and the giant otter and sea otter are the largest. They have very soft, insulated underfur, which is protected by an outer layer of long guard hairs. This traps a layer of air which keeps them dry and warm under water.
Otter’s eat fish, frogs, crayfish and crabs. They chase the prey in water.