Monday, November 29, 2010

Quiz #376 (2010-4-09) Solution


Click on picture(s) for a larger view.
Picture taken in New Jersey

Answer by Tony Leukering

Six birds with no particular distinctive shape aspects at all. Bills not long, short, thick, thin; wings not long, short, pointed, rounded; tail not long, short, forked, wedge-shaped, rounded. You might be surprised at how many species the lack of 'interesting' shape features rules out. Additionally, the birds all seem to be of the same shape and size and they are dark.

The proportions and darkness of the birds suggest some sort of blackbird, with tail length and shape ruling out many (most?) of those. A couple of the birds that we can see well, have dark streaking on paler underparts (seen best on the middle-right bird, but also visible on the upper-right bird). This, then, rules out nearly all the other ABA-area species of blackbird. Brewer's and Rusty blackbirds have longer tails and lack streaking. Except for juveniles, cowbirds lack streaking, but the rest of the plumage does not match that of juvenile Brown-headed Cowbird. Tricolored Blackbird doesn't sport a strongly streaked plumage -- particularly against such obviously paler underparts.

Assuming that the birds are all of the same species (and there doesn't seem to be any good reason why not), the upper-left bird may provide the best clue: reddish-orange lesser coverts. I took this picture of six immature Red-winged Blackbirds flying over the Cape May hawkwatch platform, Cape May Co., NJ, on 26 September 2010.

With two quizzes to go, three participants share the lead with 7 correct: Tyler Bell, Ben Coulter, and Chishun Kwong. Good luck to these and all participants!

Incorrect species provided as answers:
Pine Siskin - 1
Rusty Blackbird - 1
Phainopepla - 1

Congratulations to the 12 of 15 getting the quiz correct:
Tyler Bell
Hope Batcheller
Al Guarente
Nick Komar
Ben Coulter
Christian Nunes
Pam Myers
Tom Takano
Joel Such
Robert McNab
Marcel Such
Chishun Kwong

Answer: Red-winged Blackbird