Fabrice Cahez / Muskrat (Ondatra zibethicus) at water surface. River Allier, France, April.

Phil Savoie / Muskrat (Ondatra zibethicus) swimming, Gallatin National Forest, Bozeman, Montana, USA, May.

Phil Savoie / Muskrat (Ondatra zibethicus), swimming, Madison River, Gallatin National Forest, Bozeman, Montana, USA, May.

Loic Poidevin / Coypus (Myocastor coypus) fighting, Le Teich, Gironde, France, October

Loic Poidevin / Coypu (Myocastor coypus) swimming, Le Teich , Gironde, France, September. Introduced species.

Jiri Lochman / Giant white tailed rat (Uromys caudimaculatus) at night, Herbert River, Girringun National Park, Wet Tropics of Queensland UNESCO Natural World Heritage Site, Queensland, Australia.

Jiri Lochman / Giant white tailed rat (Uromys caudimaculatus) at night, Herbert River, Girringun National Park, Wet Tropics of Queensland UNESCO Natural World Heritage Site, Queensland, Australia.

Laurent Geslin / Coypu (Myocastor coypus) in river, Strasbourg, France. June. Introduced species.

Danny Green / Coypu (Myocastor coypus), Northern Israel, January. Introduced species.

Cyril Ruoso / Coypu (Myocastor coypus) underwater view, Burgundy, France. October. Invasive species.

Cyril Ruoso / Nutria / Coypu (Myocastor coypus) three juveniles in water, Yonne, France

Cyril Ruoso / Nutria / Coypu (Myocastor coypus) introduced species, in vegetation, France