[EBB Sightings] Photos of some recent migrants

	<940002.88130.qm at web82803.mail.mud.yahoo.com>

On Tue, 15 Apr 2008 23:10:19 -0700 (PDT), Bob Power 
wrote:

>I too am struggling with the Dusky and believe the
>broad yellow lower mandible, blocky head, off-white
>throat, and short primary projection track more
>closely with Willow Flycatcher. Willow also has a
>"whit" call, for what it's worth.

I would expect Willow to be browner, less gray on the upperparts, and have
much less or no eyering.  I think the overall shape and eyering pattern is
better for Dusky.

The mandible pattern on Dusky and Hammond's varies.  Dusky usually has more
pale than Hammond's, but the amount and distribution of dark at the tip can
be minimal.  Gray Flycatcher usually has a well defined black tip to the
mandible, while Dusky has a more blended pattern.  I think I see a trace of
dark on the bill tip of Glen's photos.  

Yes, it is early for a Dusky, but it would be virtually unprecedented for
Willow.  Willow is one of the latest Empidonax to arrive in Spring and is
seldom, if ever, seen before May.  E.g. the earliest arrival of migrant E.
traillii brewsteri in San Diego County is 11 May (Unitt).  

There is a difference in the "whit" call between the two with Dusky having
a shorter more abrupt note compared to Willow's longer more breathy call. 

Anyway, I believe Glen's photos and description support Dusky Flycatcher.
The status of Dusky Flycatcher in migration remains enigmatic and I
encourage observers to carefully document their occurrence away from known
breeding areas.

-- 
Joseph Morlan, Pacifica, CA 94044   jmorlan (at) ccsf.edu 
Birding Classes start Apr 1 in SF   http://fog.ccsf.edu/~jmorlan/
California Bird Records Committee   http://www.wfo-cbrc.org/cbrc/