Chestnut-sided warbler Dendroica pensylvanica

Identification Tips:

Adult male alternate:

Basic and immature:

Similar species:

In alternate plumage, the only other warbler with rusty sides is the Bay-breasted Warbler but it has a brown, not yellow, crown and has a dark throat. In basic (fall) and immature plumages the yellow wing bars can also be found in the Golden-winged Warbler but this species has a dark throat and cheek patch. The white eye ring, unstreaked underparts, and gray face are also good field marks.

Length and wingspan from: Robbins, C.S., Bruun, B., Zim, H.S., (1966). Birds of North America. New York: Western Publishing Company, Inc.