Sounds like the debate is about over.... Mike's Myiarchus does look like a
smaller /smaller-billed variety, and certainly his measurements agree. I
wanted to contribute one thing to the conversation that I haven't seen yet.
Mike's description of the call "choook" perfectly fits one of the standard
spring/summer calls of Ash-throated Flycatcher; if I interpret Mike's
description correctly. Some examples of the single-note call I refer to are
included within Richard E. Webster's "alarm call" recordings in
xeno-canto.org; among a variety of more complex calls. Typically, in the
Umpqua Valleys, Ash-throateds will make "took" calls occasionally, then
burst out with the whole call/song. Sometimes they make only the chook or
took calls. These are flat "toook" calls, vs the higher-pitched peeep or
weeeep calls of many of the other Myiarchus. So, I'm just saying that
Mike's description of the call is consistent with Ash-throated Flycatcher.
My experience with the other species is limited so cannot say the others
cannot make that call.
Matt Hunter
West-central Douglas County
Land of Ash-throated Flycatchers
