Tweets,

It seems I also have too much time on my hands.

Yesterday I also approached the size of the bird based on a comparison
to the "pine" needles in the photograph. I assumed that our bird was
actually in a Douglas Fir. I also remembered telling my students that
Douglas Firs have one inch needles. I ran outside and grabbed a (one)
representative needle and measured it. It was just over one inch.
Maybe I should have measured more, and maybe not. A quick internet
search brought me to

http://www.nearctica.com/trees/conifer/tsuga/Pmenz.htm
[Image]


Their description of Douglas Fir (Pseudotsuga menziesii (Mirb.) Franco)
includes:

"Needles: Needles spreading, in two very irregular rows, 0.75 to 1.25
inches in length; needles flattened, petiolate, and rounded at the tip,
flexible; color variable by range, yellow-green along the pacific coast,
and blue-green in the Rocky Mountains."

My fading memory still recalls 254 mm = 1 inch. Mike's 40 needle
average came in at 326. If we substitute the text book value of Douglas
Fir needles we get a smaller bird. When I calculated it yesterday I got
five to six inches. Still large for a Bush Tit, and the bill is weird,
but.................

Check out that tail! Marvel at how long it projects beyond the wings.
Certainly a distinctive feature. Bush Tit has a tail like that. Sibley
describes Brown-headed Cowbird as "relatively short tail".

Is this not fun?

Larry Schwitters
Issaquah




>From Mike Patterson,

There are really only 4 species of regularly occuring species
that this could be:
Adult male Bushtit - small
female Brown-headed Cowbird - medium
female Brewer's Blackbird - bigger than a cowbird
juvenile Gray Jay - pretty big

Everything hinges on the actual size of the bird. My experience
is that most people over estimate the size of a bird. I do a lot
of in-hand work with birds as a bander and I never cease to be
amazed at how much smaller everything seems in hand (Yellow-
breast Chat being the exception). Based on this I would (right
or wrong) tend to automatically reduce the claimed size of a
bird description. In this case, however, there is a reliable
visual cue- the Douglas-fir needles....

I collected and measured 40 Douglas-fir needle, obtaining an
average length of 32.6 +/- 3.2 mm. Based on this, I calculated
following (which should all be considered ballpark estimates):

overall length - 160mm (6.3 inches)
culmen length - 9mm (bill depth 6mm)
tail length - 72mm
wing length - 65mm

So, the observer's estimate was pretty good and size should effectively
eliminate both Bushtit and Gray Jay (there are all sorts of structural
reasons why Gray Jay can be eliminated as well).

And I am forced to recant my original ID in favor of (and you're all
going to hate me for this): BROWN-HEADED COWBIRD, female AHY, probably
_obscurus_ based on the bill dimensions.

--- original message ---
Subject: Bird ID help (update)
From: "Bill Ferensen" <ferensen AT hotmail.com>
Date: Fri, 11 Jun 2004 21:53:32 -0700

After some 200 hits on this picture:
http://www.pbase.com/image/29984263