The Common Muskrat is a medium/large semi-aquatic rodent living around still or slow moving water. They can be found in some of the same areas as beaver. They are smaller than beaver and have a round hairless tail. They make lodges that resemble beaver lodges but are smaller and typically made from cattails. They eat cattails and other aquatic plants, but apparently also eat various small aquatic creatures. I've seen them pulling up plants and eating the roots, completely oblivious to the group of people on the boardwalk less than 3 feet from them.