Movement patterns in the white-clawed crayfish Austropotamobius pallipes, in a Tuscan stream.

We analyzed spatial behavior in the white-clawed crayfish, Austropotamobius pallipes, inhabiting a stream in Tuscany (Italy). Our study suggests an overall complex movement pattern, where nomadic movements are intercalated by stationary phases. There was a low rate of recapture within the stretch of stream inspected, suggesting either a tendency of the species to disperse or a mortality rate caused by predators or the loss of tags with molts. However, one part of the population showed a conservative use of space, as indicated by 1) more extensive movement during a 24-h cycle than during the one-year cycle, 2) a weak tendency to return to the “home” pool if released at a distance of 50 m, and 3) an equal distribution of up- and downstream movements. No correlation was found between either 1) the displacement from the point of first capture and the length of time the specimen was followed through recaptures or 2) the number of captures and the maximum distance traveled.