Bilateral Pentadactyly in an Immature Alpine Swift (Tachymarptis melba)

An immature Alpine swift (Tachymarptis melba) that presented to a wildlife rehabilitation center was observed to have bilateral pentadactyly on examination. The supernumerary digits did not appear to cause discomfort for the bird, and no motor deficits were apparent. The skin and nails of the digits appeared normal. Radiographically, the extra digits appeared to be composed of two phalanges. The male swift was housed and fed an insectivore diet until it was fully fledged and demonstrated good flying ability. After 16 days of hospitalization, hand-feeding, and flight training, the bird was released to the wild. To our knowledge, this is the first case described of bilateral pentadactyly in an Alpine swift.