Pair nests solitarily. Young breed the following year. Subject to predation from small mammals, accipiters, and jays. One of the most generalized and opportunistic insectivorous birds in North America. Often flocks in winter, sometimes with other species.
Males tend to forage higher than females.
Commonly parasitized by brown-headed cowbird. Recent taxonomic revisions have combined the formerly separate Audubon's warbler and myrtle warbler. Foraging and habitat relations of insectivorous birds in a managed Sierra Nevada mixed conifer forest. M.S. Thesis, Univ. Airola, D. A. 1986.