A preliminary biotelemetric study of a ferai invasive Xenopus laevis population in France

The invasive African clawed frog (Xenopus laevis) is currently spreading over a large area in western France. In order to investigate the population expansion processes we studied the feasibility of implanted transmitters use. Seven frogs were radiotracked during the winter period. Even in this cold period of the year, individual movements were observed in the natural water network, and also in the flooded terrestrial surrounding area. These areas play a key role in the invasive process. During the study, freezing and predation by the polecat (Mustela putorius) seemed to be the major adult mortality factors.