Warbler Guy, do female warblers sing? Singing warbler females are common?

Nice question, Jeremiah....Answer: Among the 114 New World wood-warbler species,
I've read at least two sing: Yellow and American Redstart, according to Kimball Garrett's and Jon Dunn's "Warbler Field Guide" (Houghton Mifflin, 1997).

(Yellow Warbler above is a male; below is a female Yellow Warbler. Both sing.)

This guide is excellent and an essential companion for warbler enthusiasts.

Since its publishing date in 1997, it's possible more female wood-warbler species have been detected, though I've not read about any new discoveries.