Muskrat

The muskrat is a medium-sized semi-aquatic rodent native to wetlands, marshes, ponds and slow-moving streams across most of North America, and introduced to parts of Europe, Asia and South America, where it is often considered invasive. It has dense, water-repellent brown fur, a long, laterally flattened, nearly hairless tail used for swimming, and partially webbed hind feet, adaptations that make it an efficient swimmer despite spending significant time on land. Muskrats feed mainly on aquatic plants, supplemented by small animals such as freshwater mussels, crayfish and fish, and they build dome-shaped lodges of vegetation and mud in open water or burrow into banks, structures that also provide shelter for other wetland wildlife. The species reproduces rapidly, with females capable of producing several litters a year, which supports large, resilient populations even under significant trapping pressure for its fur. Muskrats play an important ecological role in wetlands by creating open water channels through dense vegetation, though in introduced regions their burrowing can damage dikes and levees.