What subtle feature might a keen observer notice near the eye area on a female Yellowthroat?

Answer

Subtle, dusky, or dark feathering suggesting the mask outline

While the female Common Yellowthroat lacks the male’s defining, solid black mask, she is not entirely without facial markings. A careful observer might detect faint evidence that hints at the mask pattern her mate possesses. Specifically, females can exhibit subtle feathering around the eye area that appears dusky or dark. This faint shadowing suggests the outline of the characteristic mask, providing a slight clue to her identity even though she is significantly plainer overall compared to the adult male.

What subtle feature might a keen observer notice near the eye area on a female Yellowthroat?
speciesbirdappearanceYellowthroatPlumage