Otters are classified under the subfamily Lutrinae, which has a total of 13 species in seven genera. North American river otters are found throughout Alaska, Canada and the contiguous United States. Habitat North American river otters live in a variety of habitats, but they spend most of their time in or near streams, rivers, lakes and marshes. They often build a den or a burrow in their home territory. They will if necessary, however, travel great distances over land and through water to find food.
Otters eat whatever is readily available and easiest to catch.
Reproduction Otters sexually mature at about 2 to 3 years of age. Mating occurs in the fall or spring, with birth taking place the following year. North American river otters have a delayed implantation cycle, which differentiates them from any other related otter species. May. Two or three young are born in a secluded den. However, litters may range from one to five pups.