: When swimming, a nutria's tail remains relatively still or drags behind. A muskrat’s tail undulates from side to side to help with propulsion. Habitat and Behavior
: Nutria are "intermediate" in size—larger than a muskrat but smaller than a beaver. An adult nutria typically weighs between 15 and 20 pounds. beaver rat
: The most reliable indicator. Nutria have a round, hairless, rat-like tail. Beavers have a broad, flat, paddle-shaped tail, and muskrats have a thin tail that is flattened on the sides. : When swimming, a nutria's tail remains relatively