Greetings All

Some of this is old hat and was covered by a brief article in Birding by
either Mike Patton or Matt Heindel. However, for the first time, I've heard an
apparent Willow Flycatcher give an Alder Flycatcher call (song not given). I had
always wondered if Willow-types giving Alder call notes were indeed hybrids.
However...

On Whidbey Island, in w. Washington, I had a Traill's Flycatcher giving a
call typical of an Alder Flycatcher. The bird looked absolutely typical for a
western Willow Flycatcher; though I know visual field marks for separating these
taxa are not necessarily reliable, this bird had nothing visually that would
make me think "Alder." The bird appeared to be an adult.

Previous Washington records of apparent Willows calling like Alders (these
birds were ID'd by visual characteristics and/or song) were in ne. Washington,
where one might think some gene introgression has occurred; ie, a bird calling
like an Alder but looking like a Willow might have some Alder genes.
Certainly, birds found during migration in CA could be hybrids.

But, this bird in western Washington during mid-summer seems to be at a
location and date at which a hybrid (even backcross) is unlikely; further food for
thought on the reliability of call notes in separating these species.

Cheers
Steven Mlodinow