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plete molt prior to migration. It is possible thatlong-distance migrant accipiter speciesdon’t typically molt while migrating. Perhapsdue to the Sharp-shinned Hawk’smore northerly breeding distributionand longer migration, active molt wasonly noted in individuals migratingthrough the Intermountain West (Fig.7). Perhaps individuals breeding farthersouth than the majority of the populationhave shorter migrations and can thus affordto molt and migrate simultaneously.More study is certainly needed.Cooper’s HawkBased on our observations, we found thatCooper’s Hawks are the most frequently notedraptor actively molting during migration in theWest (Figs. 8 and 9). Although other speciesseem to molt less frequently during migration,molt during migration appears to be a regularpart of the Cooper’s Hawk’s life cycle, at leastfor Western montane breeders. Cooper’s Hawksare often seen completing their prebasic moltduring September and October, typically moltingthe outer primaries and secondaries, alongwith a few rectrices. Some adults, however, areobserved earlier in their prebasic molt cycle,growing middle primaries and initiating tailmolt (Fig. 9).Fig. 5. [Top left] This adult Osprey is molting P5 and P9.Cape May Point, New Jersey; 29 September 2003. © Jerry Liguori.Fig. 6. [Bottom left] This adult Osprey is molting P5–P6and P1–P2 in two waves of a “stepwise” molt pattern.Kiptopeke State Park, Virginia; 15 September 2005.© Brian Sullivan.Fig. 7. [right] This adult Sharp-shinned Hawk is activelymolting its tail and flight feathers. The central tail feathers aswell as a middle secondary and the middle primaries are inmolt. Wasatch Mountains, Utah; 29 April 2002. © Jerry Liguori.w w w . a B a . o r g 39