Polioptila caerulea

The Blue-Gray Gnatcatcher. I was on a mission to blip a Western Scrub Jay today so I went down to Lake Chabot, where they abound in the oak chaparral woodland, but then this picture happened. Gnatcatchers are very twitchy and I rarely get decent pictures of them, so I'd rather share this than my distant, grain-tacular jay shot.

Twelve species of gnatcatcher and three species of gnatwren make up the exclusively New World family of Polioptilidae. These are tiny insectivorous birds that primarily inhabit the neotropics. The Blue-Gray Gnatcatcher is the most widespread of the four U.S. species, and the only one considered truly migratory. They winter in Central America, Mexico, and the lower reaches of the U.S., and then spread northward to breed. The three other species--Black-Capped, Black-Tailed, and California--occur in limited ranges in the southwest, where they spill over from Mexico.

The call of the Blue-Gray is a raspy "spew." I located this bird high in a tree after following its incessant, agitated spewing, which it was directing at another bird it perceived as a threat--the Western Scrub Jay.