The nutria, scientifically known as Myocastor coypus, is a large, semi-aquatic rodent also known as coypu or swamp beaver. This mammal, distinguished by its bright orange incisors and a round, rat-like tail, inhabits watery environments. While resembling beavers or muskrats, the nutria has distinct features, such as mammary glands on the female’s flanks that allow young to nurse while in water. This adaptable animal’s presence across diverse global environments prompts interest in understanding its original homeland and how it became so widely distributed.
Native Geographical Range
The nutria is indigenous to the temperate and subtropical regions of South America. Its native range extends across the southern half of the continent, including Argentina, Bolivia, southern Brazil, Chile, Paraguay, and Uruguay. Within these areas, nutria inhabit a variety of aquatic environments. They thrive in wetlands, marshes, and along the banks of slow-moving streams, rivers, and lakes.
These environments provide ideal conditions for nutria, characterized by abundant aquatic vegetation for food and suitable banks for burrowing. They construct burrows along water stretches, often with partially submerged dens. While freshwater marshes are a preferred habitat, nutria also occupy bayous, impoundments, farm ponds, drainage canals, and brackish or saltwater marshes. The mild climates of South America, along with cyclical drought-flood patterns, naturally regulate their populations.
Spread Beyond Native Lands
Nutria populations expanded beyond their native range primarily due to human activities. The most significant reason for their widespread introduction was the fur trade. In the late 19th and early 20th centuries, a high demand for their soft underfur led to the establishment of nutria fur farms in various parts of the world. These farms were initially developed in South America and later expanded to Europe, North America, and Asia.
Many nutria escaped from these fur farms, often due to unprofitable operations or accidental releases. Additionally, some nutria were intentionally released into the wild. This was sometimes done to establish game animal populations or as a form of biological control for aquatic vegetation. The first recorded introduction to the United States occurred in California in 1899 for fur farming, while significant populations were established in Louisiana in the 1930s through escapes and deliberate releases. Feral nutria populations became established across North America, Europe, Asia, and parts of Africa and the Middle East.