The effect of the postjuvenal molt in the house sparrow on infestations of the quill mite, Syringophiloidus minor (Berlese) (Acarina: Syringophilidae).

Abstract

Syringophiloidus minor (Berlese) was recovered from House Sparrows, Passer domesticus L., ranging in age from nestlings to adults. Of 492 sparrows examined, 402 (82%) were infested. The primaries, major primary coverts, secondaries and rectrices were the most frequently infested feathers. Colonization of the primary coverts and secondaries of the juvenal plumage is selective, with mites favoring those feathers which occupy positions near the end of the molt sequence. Postjuvenal molt alters the frequency of infestation of feathers within a tract and also the frequency of infestation of entire tracts or combinations of tracts. The selective value of the infestation patterns in the juvenal and nuptial plumages and the probable sources of the dispersants which colonize the nuptial feathers during the postjuvenal molt are discussed.