Fig. 4

GPS tracks of the drifter deployed in Lake Biwa. The colored arrows and crosses indicate the locations where the drifter was deployed and retrieved, respectively. Each color represents one deployment: blue (#1), gray (#2), light green (#3), light orange (#4), red (#5), pink (#6), green (#7), and orange (#8). The black arrows show the direction of drifter movement. The offshore area of the lake (depth > 20 m) is indicated by a dashed line. Note that the Argos locations of the drifter in the latter half of deployment #8 are shown with triangles and dotted lines because GPS positions were unavailable because of mechanical failure