Fig. 4.
Dispersal patterns of American redstarts inferred from δD in tail feathers molted on or close to temperate breeding sites and sampled from the same individuals in consecutive nonbreeding seasons. (A) δD differences between adult and natal feathers (δDAF − δDNF) indicated that immature redstarts overwintering in mangrove and scrub habitats differed in their natal dispersal direction. Birds wintering in mangrove forest (red circles) dispersed south of their natal area, whereas redstarts in second-growth scrub (blue circles) dispersed north of their natal area. (B) δD differences between adult feathers in the second and first year of capture (δDAF2 − δDAF1) showed that adult redstarts exhibited considerable breeding site fidelity and that nonbreeding habitat occupancy had no apparent effect on adult dispersal. Horizontal dashed lines depict the 95% C.I. (±9‰) of δD in feathers (23).