The Southern river otter is a medium-sized otter that lives in South America. Its fur is dark brown in color on the top and has a lighter cinnamon color on its underside. Although called a "river otter", it inhabits both marine and freshwater environments.
Southern river otters are found in Chile and Argentina. They inhabit marine, freshwater, and terrestrial habitats, but are mostly found in freshwater lakes and rivers having a significant amount of dense vegetation, especially along the shorelines, which must be present to use as cover. Their habitats also need the root systems of mature trees, as well as fallen tree debris.
Southern river otters are active during the night. Females and their young live in family groups, while males usually lead a solitary life.
Southern river otters breed in the winter and spring. After the gestation period of 2 months, females give birth to a litter of 1 to 2 pups, but up to 4 can also be born at a time. Pups are born altricial being blind and helpless. They remain with the family group for the first year before they become independent and reach reproductive maturity when they are between 2 and 3 years old.
Southern river otters are threatened by illegal hunting, water pollution, and habitat loss. They were vigorously hunted for their pelts throughout the last 100 years. This is the major cause of their current low population numbers and endangered conservation status. The riparian forests and rivers in which these otters are mostly found have been disturbed by human presence. Dam and road construction, as well as stream canalization and drainage for agriculture, destroy many acres of what could be habitat for this species. The continual decrease in prey numbers also causes problems for Southern river otters. Some invasive aquatic species that have been introduced into that area are limiting the mollusks and fish available for otter prey. This causes the otters to move to other freshwater systems to hunt for food.
The IUCN Red List and other sources don’t provide the number of the Southern river otter total population size. Currently, this species is classified as Endangered (EN) on the IUCN Red List and its numbers today are decreasing.