How is the Willow Flycatcher often recognized, contrasting with its subtle appearance?
Answer
Its descending “fee-bee” call
The Willow Flycatcher is known primarily not for its striking visual appearance—which is described as drab olive-green and white plumage—but for its distinctive vocalization. The specific sound that aids in its recognition is a descending call pattern described explicitly as “fee-bee.” This auditory cue is essential because, visually, the bird is subtle, sharing features like a weak eye-ring, making visual identification difficult, especially when trying to distinguish it from other species within the Empidonax genus, a challenge birders sometimes refer to as the "Empidonax shuffle."
Related Questions
How is the Willow Flycatcher often recognized, contrasting with its subtle appearance?What specific ecological feature do Willow Flycatchers strongly depend on for breeding habitat?Which recognized Willow Flycatcher subspecies generally tends to breed at higher elevations than *E. t. traillii*?What is the primary anthropogenic engine currently influencing the rapid evolution of *Empidonax traillii*?What is the typical foraging strategy employed by the insectivorous Willow Flycatcher within its habitat?How does the documented genetic adaptation rate in the Willow Flycatcher compare to typical rates inferred from the fossil record?What concept might supersede neat geographical lines when describing future population structure based on modern genetic data?What subtle facial feature is often described as incomplete or weak on the Willow Flycatcher?In the Rocky Mountains, what local selective driver might favor Willow Flycatchers genetically predisposed to earlier breeding?For a migratory species like the Willow Flycatcher, where does adaptation pressure manifest besides the breeding grounds?