California State University, Pomona
Los Angeles County, California
29 November 1999
I searched adjacent snags with no luck, but soon heard the unmistakable call of a Thick-billed Kingbird (a rising and loud "prrrreeeeet") from near the tops of the Sycamores. However I could not locate the bird. Flocks of Cassin's Kingbirds started to arrive. Finally I gave up and was heading back to the car when I noticed the Thick-billed Kingbird was back on its original perch. This time I got my scope on the bird and was afforded excellent views for about 10 minutes during which time the bird caught several insects and returned to its perch each time.
The following description is based on notes taken while watching the bird:
Obvious kingbird, slightly larger than adjacent Cassin's Kingbird and with a much heavier, more massive dark-colored bill. The bird was overall dark above and bright yellow below contrasting with white throat.
The crown was relatively flat, but peaked toward the rear. The head was dark gray-brown with a yellow crown stripe visible once when the bird bent its head down. A blackish mask extended from the bill to behind the eye, but it did not contrast much with the overall dark color to the head. The white throat was very prominent and it wrapped back under and behind the ear coverts. I believe this pattern may be diagnostic.
The back and wings were dark gray, with paler gray-brown edges to the wing coverts. No visible rust was evident on the wing coverts or the tail. The underparts were bright lemon yellow, from the undertail coverts all the way up to the top of the chest where it faded to the white of the throat and chin. A dark feather crease was evident mid-breast, between the pectorals. The tail was dark-brown and clearly notched at the tip but without any visible pale edges or fringes. In flight the wing-linings appeared bright yellow; same color as the breast.