Monday, April 26, 2010

Quiz #346 (2010-2-04) Solution

Click the picture for a larger view.

Answer by Margie Joy and Tony Leukering

Margie Joy provided a fairly thorough answer, so I'll start off the solution with it.

"The leftmost bird is a merganser. There are four mergansers on the ABA list: Common, Red-breasted, and Hooded mergansers and Smew. Unless I'm really thrown off by the angle of the bird, the bill is too short and pale to be that of a Common or Red-breasted Merganser and too pale to be that of the lovely Smew. That leaves Hooded Merganser. Still looking at the bill, it seems pretty orangey to me, but not the deep red-orange of Common or Red-breasted; Id call it warm straw-yellow. Perhaps the most striking feature is the crest: warm brown in color and spiky, giving the head an oval shape and a frosty or haloed look in the light, consistent with female Hooded [but see below!]. Although females of Common and Red-breasted have warm orange-brown crests, Common's is short and redder in color and Red-breasted's is described as wispy, and both have a slightly flat-headed appearance. The dark back and paler neck further point to Hooded.

"The blackish bird near the center of the group (4th from left) is a coot. After considering Eurasian Coot because of the all-black undertail coverts, I decided on American because of the shape and extent of white on the bill and forehead. I felt that this was a more diagnostic feature.

"There are five ducks that I can positively identify as wigeons. Three of them, the leftmost, rightmost, and rearmost birds, look to be male American Wigeons, with all showing at least some green coloration on the head with pale crowns and dusky warm brown sides. Two others (the second bird from the left and the one to the right of the coot with its bill in the water) show wigeon-shaped heads with dark smudging above the eyes and warm rusty-brown sides, pointing to female American Wigeons.

"That leaves the second bird from the right in the middle of the wigeons. It seems to be about the same size as the wigeons, but it's difficult to tell for sure. It could be slightly larger. It floats high on the water like the wigeons, but its neck is longer or perhaps just held in a more upright position. Its face and head are quite plain, a bit darker on the crown with just a faint line from the eye to the bill. Its bill is short like those of the wigeons, and has some orangey color to it rather than the blue-gray of wigeons. The head and neck are pale, contrasting with the darker gray-brown body. All signs seem to point to Gadwall."

Thanks, Margie.

I want to delve a bit more deeply into a few of the birds here, particularly the Hooded Merganser. My first point is that the merganser is smaller than the other ducks, thus ruling out the larger species. My second point is that all respondents that noted such, identified this bird as a female (fortunately, none of them included their guesses on sex directly in the species answer). However, mergansers exhibit delayed plumage maturation, unlike bay ducks (Aythya), with young males looking like females. The first-cycle males retain this female-like plumage into their first spring, so without being able to see details of the wing plumage and without knowing the date of the photo, this bird is not certainly sexable.

I assume that the folks mis-identifying the Gadwall as Northern Pintail did not take into account the bill color, nor the neck-chest contrast noted by Margie. Finally, the female wigeon show gray heads contrasting rather strongly with browner chests, which help to rule out Eurasian Wigeon; on the right-most of the two, we can just see a bit of the inner secondary and it is not obviously white, so another point for American Wigeon.

I took this picture of a female or immature male Hooded Merganser, American Wigeon, American Coot, and female Gadwall at Lily Lake, Cape May Point, Cape May Co., NJ, on 24 December 2009.

Two respondents' answers provided no incorrect species, but did not provide enough correct ones. Additionally, one respondent's answer was precluded from being correct for the competition, as it included the ancient 'd' that is no longer part of 'wigeon.'

Incorrect species provided as answers:
Red-breasted Merganser - 3
Northern Pintail - 2

Congratulations to the 17 of 24 getting the quiz correct:
William Velmala
Su Snyder
Thomas Hall
Chris Warren
Roy Myers
Kevin Kerr
Aaron Brees
Bryan Guarente
Nick Komar
Margie Joy
Robert McNab
Peter Wilkinson
Marcel Such
Joel Such
Tyler Bell
Judi Owens
Tom Wilberding

Answer: Gadwall, American Wigeon, Hooded Merganser, American Coot