More muskrat love! Did you know Muskrats eat phragmites?!! They gnaw off the emerging and exposed shoots at the base and then eat the green stems. Very cool. Other fun facts: Muskrats can hold their breath underwater for up to fifteen minutes. They can also chew underwater. Unlike beavers, whose tails are flattened horizontally, a muskrats tail is laterally flattened (in other words vertically). The tail functions like a rudder to help the Muskrat maneuver through water. Muskrats can swim forward and backward.