Figure 8. Comparison of tail shape on a partially spread tail, extent of white on the undersurface of the tail, and pattern of white on the outer tail feathers: Leach's (left), Band-rumped (middle), and Wilson's (right) Storm- Petrels. Note relative depth of tail forth; depth of tail fork does not overlap between Leach's (T6 16-26 longer than T1) and Band-rumped (4-12) and Wilson's (range 0-8). Also compare leg length between Band-rumped and Leach's (both species-range 21-25.5) vs. Wilson's (33-36). (Measurements in millimeters from BWP.)
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