Leadership of Winter Mixed-Species Flocks by Tufted Titmice (Baeolophus bicolor): Are Titmice Passive Nuclear Species?
Figure 1
(a) Illustration of one example of the hypothesized relationships between the overall flock movement path (using successive flock centers to chart the path; black line) and the movement paths of two individual flock participants: TUTI (nuclear species; dashed line) and a satellite species (dotted line). (b) Diagram of a 15-minute portion of a flock movement path with T 0, T 1, T 2, and T 3 representing estimated flock centers at 0, 5, 10, and 15 minutes respectively. Lines S 1, S 2, and S 3 represent “movement” segments between estimated flock centers, with the length of the line representing the movement distance of the flock and the arrow showing the overall flock movement direction (azimuth) between flock centers. Dashed lines (SPECIES 1 and SPECIES 2) represent the observed movements of 2 randomly selected birds observed while at flock center T1 (to be correlated with flock path). Dashed lines at T3 represent the movements of a FOCAL BIRD and a RESPONDING BIRD (an individual in the same general area that moves immediately after the focal individual moves) to be correlated with each other for within-flock analysis. These observations were made at all flock centers.
