Yes, Hanna (in Fargo) it's true — some female wood-warblers sing.
But not many.
In fact, it's a lonely "crowd" of two female USA-based wood-warbler species — Yellow and American Redstart — that sing, according to to Jon Dunn & Kimball Garrett, author of the "Warblers" field guide (Peterson Guide Field Guide Series, Houghton Mifflin, 1997).
BUT: There's good news. I recently listened to the American Birding Association's weekly podcast. A guest on that episode noted that more female songbird order species are now known to sing than previously thought. Amazingly, she claimed her research and other field professionals have determined that recent studies indicate new additions to the female choir are ongoing.
Does that mean more than two female breeding USA wood-warbler species are now should be added to the Dynamic Duo represented in the past by merely the Yellow and American Redstart?
I'm not sure, but your question prompts me to write Dr. Garrett and Mr. Dunn...and, indeed, I may see both of them in 2021 at an upcoming conference, if the virus dynamic relents and, in turn, in-person meetings again occur. Stay tuned.
Meanwhile, and lastly:
Your question relates to the larger question of how singing birds develop their song.
In general, the prevailing theory until recently was that few female songbird order members (and MERELY the two aforementioned breeding USA wood-warbler species) possess physical attributes designed to memorize and learn their song (ala the males that MUST have a singing mentor from which they hear, learn, and memorize a vocalization).
Next, note that wood-warblers are like most other songbirds. They experience a period of practicing a song in a stage that is called "plasticity."
Depending on the species of wood-warbler, true, definitive adult song is achieved by no later than the commencement of the following breeding season after a newborn singer arrives in a previous year's brood.
When that moment of virtuosity appears, it's called "crystalization" (when complete, full, learned song can be repeated by an individual).
Now there's a magnificent term that rings a chord of delight in any birder's heart.
Meanwhile, I'm Ready, Set, Go for the spring migration north of the wood-warblers? Are you?
We're lucky in the SF Bay Area where I live and conduct regular birding tours as a Birding Guide to detect Orange-Crowned Warbler as early as the first week of February annually....with a vanguard of other family cohorts soon to follow as late winter ends and spring arrives, including: Wilson's; Black-throated Gray; Hermit; Common Yellowthroat (another subspecies arrives to join a resident subspecies in the SF Bay Area.....and/or passes through the area heading north); Yellow-rumped (individuals arrive from the south, perhaps, with other "over-wintering" individuals leaving and heading north; and, perhaps, Northern Parula (periodic nester in Marin Co., per recent eBird reports from the 2000s forward to the current date).
Regards, Daniel Edelstein
Certified Wildlife Biologist Asc.
College Instructor for all birding classes at Merritt College (Oakland, CA)
WarblerWatch.com (hosts my resume)
WarblerWatch.blogspot.com (this 15-year-old wood-warbler blog)