I show cases of atypical molt in the primaries of Harris's Hawk (Parabuteo unicinctus harrisi). Molt of the primaries in accipitrid raptors typically proceeds sequentially one feather at a time from the inner primary, P1, to the outer primary, P10. In larger species, not all primaries are replaced annually, resulting in Staffelmauser (“stepwise” or “relay” molt). From 2002 to 2022, I captured 545 Harris's Hawks in south Texas, either undergoing or having finished third prebasic molt or older, undergoing the second prebasic molt, or in Basic II plumage. I report herein on 6 instances in which 1 or more primaries were skipped or replaced out of order during the annual molt in Harris's Hawk: 5 undergoing the second prebasic molt and 1 undergoing third prebasic molt. I found 1 published case of skipped primaries in Griffon Vultures (Gyps fulvus) and another in a White Stork (Ciconia ciconia). One possible cause of this could be damaged primary follicles.

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