Quiz #426 (2011-4-08) Solution

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Solution by Tony Leukering

As noted by Robert McNab, using only a single field mark, this bird would be impossible to separate from Nutting's Flycatcher! Yes, the quiz bird and Nutting's Flycatcher share the character of orange mouth linings, but I don't think that anyone actually thought that this bird could be a flycatcher!

We don't have a lot to go on to winnow the possibilities, but the generally white coloration with, apparently, gray wings, webbed feet, and dark eyes and legs might plop us into the Laridae, home of the gulls and terns. Dark legs are not common in gulls, but relatively so in terns, so let's start there. With the foreshortening of the bill due to the picture angle, determining bill length is problematic. However, bill color is accurately gauged: yellow with a dark tip. That greatly whittles the possibilities among the tern species recorded within the ABA area, as only Least Tern sports such a bill pattern, though Large-billed might at times. However, neither of those species sports black legs, so into the gulls we go.

ABA-area dark-legged gull species include Ivory, Franklin's, Laughing, and Heermann's gulls and, of course, Black-legged Kittiwake. The gray wings of our quiz bird rule out Ivory Gull and the white body does the same for Heermann's Gull. The paleness of the wings and the bill color rule out Franklin's and Laughing gulls. However, it should be noted that even ignoring the black legs, the unmarked white underparts on an immature gull (note the black on the tail) actually rule out nearly all options. Steve Mlodinow took this picture of a 1st-cycle Black-legged Kittiwake -- one of an amazing two present -- at Windsor Lake, Windsor, Weld Co., CO, on 5 May 2011. One of the birds had been present since early April!

Incorrect species provided as answers:
Ring-billed Gull - 2
Mew Gull - 1

Congratulations to the 18 of 21 getting the quiz correct:
Thomas Hall
Pam Myers
George Cresswell
Peter Wilkinson
Patty McKelvey
Robert McNab
Jennier Courtemanche
Christian Nunes
Ira Sanders
Tammy Sanders
Josh Parks
Margie Joy
Su Snyder
Devich Farbotnik
Nick Komar
Al Guarente
Kirk Huffstater
Bryan Guarente

Answer: Black-legged Kittiwake

Quiz #425 (2011-4-07) Solution

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Solution by Tony Leukering

This week's quiz bird resulted in answers citing six species of blackbird. In blackbirds, eye color is useful, so we'll start there. Our bird's dark eye should rule out most Boat-tailed and Great-tailed grackles (except for females of some Gulf of Mexico populations of the former) and adult Common Grackles and Bronzed Cowbirds. Granted, that leaves a lot still in the possible solution set, but we can narrow things down from here. Knowing our bird's age would help tremendously, but ageing many blackbird species in the field is quite difficult, if not impossible, as they generally conduct extensive preformative molts, thus immatures are very similar in most respects to adults.

The streaky blackbirds (Red-winged, Tawny-shouldered, and Tricolored) are eliminated by the lack of streaks; any individual of the two species that isn't obviously blackish would have streaks. Common Grackle never shows such pale head and underparts, particularly the former, and because of the latter, it does not show the contrasting dark feather centers of the underparts of our quiz bird. Brown-headed Cowbird can be ruled out by our bird's lack of contrastingly pale throat bordered by dark lateral throat stripes. Female Shiny Cowbird is never this cold-colored gray-brown and the bird is not a juvenile Shiny because it lacks streaks and wingbars. Our quiz bird is not a Bronzed Cowbird, as that species never shows even this prominent of a pale superciliary, particularly in front of the eye. Additionally, that species has a deeper and shorter bill than sported by the quiz bird. The large-tailed grackle species are just that, large-tailed, which our quiz bird is not.

That leaves us with the Euphagus problem. Though field guides may make Rusty and Brewer's blackbirds seem relatively simple to separate, the two are often quite similar, with some individuals probably best left unidentified. However, this bird is not one of those. Even the dullest and youngest of Rusty Blackbirds would show a much more obvious superciliary, while only the very youngest would still show a dark eye, but should not upon completion of its preformative molt (which is true of this bird). Additionally, female Rusty Blackbirds show auriculars more sharply-defined as a patch by rear and lower borders that our bird lacks. Finally, the bill's depth is a good indicator of Brewer's Blackbird, but, perhaps, not definitive. However, something not shown in field guides is the distinctive upright-and-head back strutting of Brewer's Blackbird that I find very useful in identifying the species, even separating it from Rusty Blackbird. Our quiz bird illustrates that behavior as well as any static picture can.

Peter Wilkinson tops the leader board with a perfect 7-for-7 score in this quarter's competition, with Al Guarente and Thomas Hall being one correct answer behind. As for the yearly competition, two Californians -- Robert McNab and Pam Myers -- lead with 35 correct responses, with Marcel Such and Peter Wilkinson right on their heels with 34 correct, and Bryan Guarente two back at 33.

Incorrect species provided as answers:
Bronzed Cowbird - 1
Shiny Cowbird - 2
Common Grackle - 1
Brown-headed Cowbird - 1
Rusty Blackbird - 2

Congratulations to the 14 of 21 getting the quiz correct:
Thomas Hall
Robert McNab
Al Guarente
Patty McKelvey
Richard Jeffers
Christian Nunes
Margie Joy
Peter Wilkinson
Josh Parks
Margaret Smith
Bryan Guarente
Nick Komar
Sean Walters
Devich Farbotnik

Answer: Brewer's Blackbird