POLYMORPHIC FLIGHT-FEATHER MOLT SEQUENCE IN TUFTED PUFFINS (FRATERCULA CIRRHATA): A RARE PHENOMENON IN BIRDS

Abstract

Abstract Previous reports have stated that Tufted Puffins (Fratercula cirrhata) lose all of their flight feathers simultaneously (or nearly so) during flight-feather molt and replace them in no apparent order. In contrast, we found that captive second-year (SY) Tufted Puffins (1) typically require 15 and 10 days to lose their primaries and secondaries, respectively, during their first flight-feather molt, and an average of 21 days to lose all of their remiges; and (2) replace their primaries in either of two discrete sequences. In 9 of 13 birds, primary molt began at the innermost primary, P1, and progressed distally to the outermost functional primary, P10. However, in the remaining four birds, primary molt began in the middle of the primaries (P5-P7) and progressed both distally to P10 and proximally toward P1. Before the proximal wave reached P1, a second wave of molt was initiated at P1 and progressed distally, typically replacing P2 and P3 before reaching the proximal wave. Such polymorphism in fligh...