The coypu (Myocastor coypus) is a large-sized rodent introduced from South America, and has been designated as a specific alian species since 2005 by Japanese government. However, the knowledge of its biological charateristics necessary for pest control is scanty. Thus, we are coducting related research on the coypu from various angles. We have revealed that the coypu has a high level of learning capability. It also has a high physical potential, such as climbing over a fence about 70 centimeters tall. In the historical aspect, we have also revealed that the background for the spread of the species in Japan has not been as has been told before. There was a nationwide campaign for promotion of the propagation of the coypu for meat production increase in the WWII postwar food shortage period.