Quiz #295 (2009-2-03) Answer

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Answer by Tony Leukering

As noted by all respondents, this week's quiz bird is a duck. Those providing their rationale took a variety of tacks to get to the right answer. In fact, despite our inability to determine most of the bird's upperwing pattern -- often a crucial part of flying-duck ID, any number of ways can get us to this week's correct answer. Tne most efficacious among these might be the bill (black), the chest (vermiculated), speculum (there is quite a bit of white on a number of secondaries), the strong gray aspect to the body plumage, and the bit of rufous in the median or lesser coverts (it's a bit hard to tell exactly to which tract those feathers belong).

Quite a few ABA-area ducks sport all-black bills in one sex and/or the other, including Fulvous-Whisting-Duck, Gadwall, Falcated Duck, all four teal, Northern Pintail, Canvasback, all three scoters, Harlequin Duck, the two goldeneyes, the two small mergansers, and the two stifftails (Ruddy and Masked ducks).

Starting with the chest would rule out all diving-duck options, but leave us with nearly all of the dabbling-duck possibilities.

Starting with the white in the speculum, we would begin with Gadwall, both scaup, Tufted Duck, White-winged Scoter, all three Bucephala, all four mergansers, and Masked Duck. Hmm, note the near lack of correlation between this solution set and the two above?

The gray body plumage, including the chest, would leave a solution set starting with Gadwall and ending with Falcated Duck (a couple of fairly closely related beasties).

Finally, the solution set resulting in starting with rufous median and/or lesser coverts is exactly one species long: Gadwall.

I took this picture of a male Gadwall flying up the Arkansas River at Valco Ponds S.W.A., Pueblo Co., CO, 20 December 2008 on the Pueblo Reservoir CBC.

One respondent involved her/his stab at the species ID with his/her guess as to the bird's age and sex. Fortunately for that person, all aspects of that answer were correct. However, if s/he had missed hit on even one of those features other than ID, the response would have been considered incorrect for the competition, though that person's name would have been listed as being correct. Please, when submitting an answer for the quiz, separate your guesses as to age, sex, subspecies, political persuasion, or any other bit that you care to guess on from your answer as to the ID of the species. Finally, that respondent may not know that guessing the age on this bird may have sent the answer astray. That is because 1st-cycle male dabbling ducks (for the most part) look very much like older males, however this bird's tail is not worn as would be typical of an immature male.

Tallies of incorrect species provided in answers:
Green-winged Teal - 1

The 31 of 32 providing the correct answer:
Peter Wilkinson
Robert McNab
Joel Such
Chris Warren
Aaron Brees
George Cresswell
Todd Reeves
Barbara Deneen
David Hartley
Jonathan Lautenbach
James Stephenson
Ned Keller
Peter Burke
Victor Germain
Andy Dettling
Tom Parchman
Tyler Bell
Marcel Such
Al Guarente
Mark Dettling
Thomas Hall
John Bissell
Chuck Carlson
Terry Nelson
Su Snyder
Bryan Guarente
Mark Gabriel
Matt Webb
Chishun Kwong
Nick Moore
Andrea Smith-Guarente

Answer: Gadwall

Quiz #294 (2009-2-02) Answer

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Answer by Tony Leukering

Wow, another single bird, and not a gull, duck, or shorebird!

This week's raptor (and all respondents got at least that far correctly) is perched on the crossarm of a power pole (these poles do NOT carry telephone lines, most of which are buried). Looking at the bird's size relative to the width of the crossarm, the bird is fairly small, say crow-sized or smaller. That enables us to ignore those typical pole-sitters, the large buteos, and a host of other streaky possibilities, leaving us with the following: Mississippi, White-tailed, and Hook-billed kites; Northern Harrier; Sharp-shinned and Cooper's hawks; Broad-winged, Gray, and Red-shouldered hawks; and American and Eurasian kestrels, Merlin, Hobby, and Peregrine and Prairie falcons among the Falconidae.

With so many options to consider, it would be good to find a single feature that can eliminate options in job lots, rather than having to struggle through species-by-species. Well, there are three such features on the bird's head. The first is iris color. While the bird's eyes are partly closed and we might be a bit suspicious that there is not enough eye visible to be sure that we're not seeing just pupil, the fact that the sun is shining and is seemingly fairly bright suggests against that (with bright sun, the pupil should be small, not large). So, with that consideration, the dark right eye should enable us to remove the accipiters. Yeah, two species doesn't quite make a job lot, but....

The second feature on the bird's head that can rule out numerous options, and the most efficient one, is a bit difficult to see. However, enlarging the picture a bunch should enable us to see that the maxilla (upper mandible) has an extra 'tooth' to it. Rather than the cutting edge curving smoothly to the bill's hook, there is a protrusion at the curve that forms an extra bump. This is a feature found, among ABA raptors, only on falcons and is one of the idenifying features of the group.

This brings us to the third feature. Except for the falcon options, all of the species listed above have streaky plumages ONLY when juveniles. If we focus on the bird's cere (the fleshy part at the base of the maxilla), we can see that it is bright yellow. On raptors, the presence of a bright yellow cere is virtually certain proof that the individual is an adult; juveniles have duller ceres, often bluish.

So, not only do we now know that our mystery bird is a falcon, we can also eliminate male American Kestrel and adult Peregrines and Prairies (the latter of which are spotted, not streaked). The pale ground color of the underparts feathers rules out male Eurasian Kestrel. Continuing our perusal of the bird's head, we can see that there is virtually no malar stripe (moustache), a feature so typical of falcons and found on all of our remaining options. Yikes! Then where did we go wrong?

Well, we didn't. Yes, moustaches are a strong feature of most of our options, but it is much weaker on Merlin and the prairie race nearly lacks the feature entirely. As the color of the bird's streaking and crown are both fairly pale for Merlin (suggesting Prairie Falcon), we can use this as confirmatory features of our ID of the bird. I took this picture of an adult female richardsonii Merlin near John Martin Reservoir, Bent Co., CO, on 17 December 2008 during the Christmas Bird Count.

Tallies of incorrect species provided in answers:
Northern Goshawk - 1
Cooper's Hawk - 4
Sharp-shinned Hawk - 2

The 20 of 27 providing the correct answer:
Peter Wilkinson
Chris Warren
Aaron Brees
Victor Germain
Andy Dettling
James Stephenson
Mark Dettling
Tom Parchman
George Cresswell
Ned Keller
David Hill
Thomas Hall
Al Guarente
Terry Nelson
David Hartley
Tyler Bell
Su Snyder
Joe Bens
Marcel Such
Bryan Guarente

Answer: Merlin