Subject: Bird ID help (update)
Date: Jun 13 10:10:10 2004
From: Mike Patterson - celata at pacifier.com


Okay, first the disclaimers:
1. This post contains some use of mathematics.
2. It's Sunday, it's raining, CostCo isn't open yet so
I can't go shopping.

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

Two people suggest Bushtit. Rule that out. This bird is larger, I recall
from observation, but also the long tail and larger bill are
inconsistent
with a Bushtit.

Gray Jay. Not often seen in the city. The bird pictured is smaller,
estimated 7 inch length.

Immature Starling. No, tail too long and the bill broader and shorter.

Phoebe. Size is right. Which Phoebe?

Bill F.


--
Mike Patterson
Astoria, OR
celata at pacifier.com