A muskrat is a small semi-aquatic rodent with dense glossy brown fur and a hairless tail. The muskrat gets its name from its rat-like appearance and a musky odor that is produced by its scent glands. Muskrats are animals that need to be around water. They build their dens in or alongside water and feed primarily on the aquatic plants surrounding their dens, such as cattails, water lilies, and duckweeds. Occasionally, they will even eat crayfish, snails, mussels, frogs, and insects.