Thanks everyone, for your responses to the Eureka, CA mystery bird! And
indeed, this photo made for a good exercise in using photos for bird ID.
http://tinyurl.com/ntcalb

Plausible guesses include:

1. Hooded Oriole (I looked them up in the breeding bird atlas for
Humboldt County and they have been fairly regular nesters in residential
areas of Eureka with planted palms. Would account for apparently
decurved bill and overall coloration, but tail looks too short for an
oriole. Could the short tail be an artifact of the bird's posture or
camera perspective?)

2. Bullock's Oriole

3. Western Tanager (Accounts for relatively short tail, but not longer
decurved bill).

4. American Goldfinch (with long-bill syndrome--pretty doubtful; could
the long bill be an artifact of the camera and bird movement? Other
American Goldfinches were present at the location when this photo was
taken.)

This photo is just blurry enough to leave me uncomfortable with a
definitive ID. Unfortunately, the person who took this photograph is
unfamiliar with bird songs and calls, and is not an experienced birder,
so I have no other information in terms of sounds, size, behavior, or
jiz.

(Please note: The mystery bird SOUND submitted by someone else was
unrelated to the bird in this photograph.)

Angela Percival
Angela at Stillwatersci dot com
Cooper Point, Olympia, WA