Black Phoebe casting a pellet
I found this Black Phoebe last week on the property of the Fremont County Sewer District near their sewer plant where I have seen Black Phoebes for several years. As I watched the bird tossed it's head downward and I caught it in the act of casting a pellet, something more often associated with owls. However Black Phoebes and other birds that eat insects or other live prey whole do this to get rid of the digestible parts. Though a real sharp photo below, it does show the pellet and it's size relative to the bird.
Casting of pellets by Black Phoebes is noted in Birds of North America (p. 6). I have only seen a Black Phoebe cast a pellet on one previous occasion. I have previously blogged a sequence of photos of a Scissor-tailed Flycatcher (and sharper than this one) as it cast a pellet. SeEtta