Dead Bird Quiz answers

22 05 2012

OK, so both of these birds are ducks. That was clear to everyone who responded to this quiz. But what sort of ducks? Bird A, which was merely a skeletal head, is definitely some kind of sea duck, what with that hooked beak tip and very thick ridges along the bill edges. Guesses on this one were Northern Shoveler and Common Eider. So let’s look at those two. The Northern Shoveler has an absurd looking bill, which makes up more than half of the total head plus bill length. As blog reader Wouter pointed out, it would be helpful to view the bill of Bird A from above to see if it’s wide enough to be a Shoveler’s. Well, Wouter, request granted! Here’s another shot of Bird A’s bill, showing that it’s pretty narrow, and helping us rule out the Northern Shoveler, whose bill would have a prominent, spatula-like appearance at its tip.

Aerial view of Bird A’s head.

Northern Shoveler: comical bill appears longer than the head itself.

What about Alicia’s suggestion of Common Eider then? Certainly, there are some similarities there, but if you look at the shape of the nostril, the Common Eider’s is elongated and placed lower on the side of the bill than our Bird A, whose nostril is very close to the top edge of the bill, and has a more open, almost triangular shape. So where does that leave us? I would posit that Bird A is a White-winged Scoter. The nostril shape and position are right, and while the demarcation between feathered area and bill is mostly obliterated, I can persuade myself that the profile of that line would have been consistent with WWSC. What do you think, Seanetters?

Bears some similarities to Bird A, but note shape and position of nostril.

Is this our bird? I would say yes!

Bird B is an easier case, and Wouter and I both agree, this is a Long-tailed Duck. The pinkish band on the bill marks it as a male, and the white neck followed by a wide black band on the breast, and then a white belly tell us this bird is still in its winter plumage, and had not yet acquired the full breeding plumage seen later in the year. Like many ducks though, the LTDU undergoes some complex interrupted and partial molts, changing its appearance almost continuously from April to October. What a pain for Dead Bird Quiz devotees, huh?

Long-tailed Duck in winter/spring.

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Dead Bird Quiz answers

2 06 2011

Bird A was a Greater Shearwater

I am trying to write intelligibly despite the maddening itch of a gazillion black fly bites. (The black fly being the state bird here in New Hampshire.) In any case, we got a formal guess on this week’s quiz from my dear, good sport of a friend, Sarah Kern, who is not even a Seantter, but who is a dead animal enthusiast. Her guesses (Double crested cormorant and eider) mirror all the emailed guesses I got from people too shy to post their guesses on the blog. HAHA! I have fooled you all! Both birds here were quite tricky though. Bird A is a Greater Shearwater. How can I tell? Well, the tube structure on the bill is just barely visible in this photo. The head does, at first glance, look like a cormorant, but that seems to be because all the feathering and skin have decomposed in the chin area, causing it to resemble the chin patch of a cormorant. Other clues that this is a shearwater are the feet. Shearwater feet are rather dainty, and fold up into a very slender bundle of grayish toes. Cormorants, on the other hand, have robust, black feet with all toes being webbed. Their feet never really fold up and look as skinny as the feet of the shearwater in this photo. Finally, cormorants have an all black wing, including the underwing. Greater shearwaters have a black upperwing and white underneath.

Summer is the time that Greater Shearwaters (which breed in the southern hemisphere) come up to our waters for vacation. In some years, we see sizeable numbers of the birds washing up dead on east coast beaches from Florida to Massachusetts. We’ll see if this specimen is an early indicator that this will be such a year.

 

A dead Long-tailed Duck from another beach. Note the brownish underwing coverts.

Bird B is a Long-tailed Duck (at least by my reckoning), but could easily be confused with an eider. A duck with striking black and white plumage should always bring to mind a male Common Eider. But our Bird B is too small. The wing chord in this guy is only 22.5cm. Common Eider wings range from 25-30cm. Aside from that, our Bird B has a rusty brown color to the underwing coverts. While live bird field guides generally show the underwing of Long-tailed Ducks being all dark, those of us who spend time in the company of dead birds know that the brown color can be appreciated up close, and when the bird is lying upside down in the sun.

The other telling detail is the black band running along the mid-back down to the tail. It’s hard to appreciate it in Bird B’s current state of dishevelment, but compare it to a more put together specimen found on another beach on another day.

An intact, dead Long-tailed Duck. The black band extending to the tail is still somewhat visible in our Bird B.





Dead Bird Quiz answers

22 02 2011

Mary Wright and John Stanton can always be relied upon to answer, and on this quiz, I even got my good friend Sarah Kern to take a look and offer her guesses. The Dead Bird Quiz is clearly catching on!

So, here are the answers insofar as I have any:

Razorbill tail projects beyond the feet.

Murre tails are quite stubby and end well short of the feet

Bird A: John and Mary are both right, in my opinion. It’s definitely an alcid (black and white bird with white-tipped secondary feathers; small, webbed feet) and the wing chord of 22cm makes it much too big to be the diminutive Dovekie. John answered that it’s either a Common Murre or a Thick-billed Murre. Mary wrote that the wing chord is too long to be a Common Murre, so it must be a Thick-billed. True indeed, the wing chord range for a Common Murre is 19-21cm, while the range for the Thick-billed is 20-22cm. The only trick here comes with the variability we find in our volunteers’ wing chord measurements. Published data on wing chords tends to be more constrained in their ranges because the data are generated by fewer observers with extensive experience. Our volunteers typically show more variation in their measurements, so while Thick-billed is by far the most likely i.d. (an inch is a lot when it comes to wing chords, after all), we cannot entirely rule out the possibility that it’s a Common Murre. Finally, why not a Razorbill? The measurements match, and without the head, how can one tell? Mary solved this mystery as well, pointing out that Razorbills have longer tails. In fact, Razorbill tails extend past the feet, while murre tails don’t even come close.

Bird B, as both Mary and John assert, is a female Common Goldeneye. The golden colored iris that gives the bird its name is, sadly, not often evident in dead specimens. But in a whole carcass, there are plenty of other markings that identify this species. For females, these include a reddish-brown head,  a dark bill that develops a small amount of  yellow at the tip in adulthood, a gray back and breast with a white belly.

Female Common Goldeneye: this photo shows the extensive white speculum on the wing.

Finally, Bird C. This one, not surprisingly, has caused the most trouble. It was not very fair of me to withhold the wing chord on this one, which was 24cm. Even with the caveat given above regarding wing chords, that is well outside the range of the little Bufflehead (wing chord: 14-18cm). So, given that relatively large size, another possibility is Mary’s answer, Long-tailed Duck. Mary also hedged with the comment: “maybe those white feathers aren’t scapulars, but the inner part of the wings . . . We await the official word from Sarah . . .” While I cannot profess to have the official word, being only a self-taught dead bird afficionado, I contend that this is another Goldeneye. Just as Mary said, the white feathers on Bird C are not scapulars, but are part of the wing proper; Bird C has a white speculum that extends almost to the leading edge of the upper wing. From the wings only, I don’t think it’s possible (at least for me) to determine whether this is a Common Goldeneye or a Barrow’s Goldeneye, though the Barrow’s is a much more northern species and Cape Cod (where Bird C was found) is the southern limit of the Barrow’s typical range, so odds are that Bird C is a Common.

Bufflehead (male) upperwing: similar to Goldeneye except MUCH smaller.

Long-tailed Duck in flight: the wing proper is all dark. White feathers are limited to the back and scapular region.

Common Goldeneye (male) upperwing.





Dead Bird Quiz Answers

27 01 2011

Thank you to my most reliable pair of DBQ devotees: Mary Wright and John Stanton, who both proffered answers to this week’s quiz. Both Mary and John id’d one bird as a Greater Scaup, and I concur that our Bird B is indeed a scaup. Whether it’s a Greater or Lesser is actually rather tough to tell from this photo alone. At least for me. Take a look at these photos and decide. I would argue that from the angle we have on our Bird B, it would be a tall order to tell.

Bird B: Lesser scaup?

or a Greater Scaup?

As for Bird A, I side with Mary on this one. I think this is a Long-tailed Duck (non politically correct name: “Oldsquaw”). And based on the pink area on the middle of the bill, I think it’s a male. Long-tailed Ducks are interesting for many reasons, not least is the remarkable difference in appearance between the breeding and non-breeding plumages (see photos). Further complicating matters, Long-tailed Duck males do not proceed in an orderly fashion from one plumage to the other, but undergo a series of changes in variable fits and starts that make the months from April to October one endless wardrobe change for this species.

 

John, if you feel strongly about a Ring-necked Duck being one of these specimens, then let us have a duel. I will meet you at daybreak on the cliffs of Weehawken. (Sorry, Alexander Hamilton humor, which I suspect is not universally appreciated.)

Male Long-tailed Duck in breeding plumage.

Male Long-Tailed Duck in winter plumage. Our Bird A was one of these.





Dead Bird Quiz Answers

16 02 2010

New Jersey is just about as far south as one might expect to see a Dovekie in winter.

Ding Ding Ding! Mary Wright nailed the Dead Bird Quiz with her responses of A)Dovekie and B)Long-Tailed Duck. Has a challenger emerged to the primacy of Doug Suitor? Doug himself tipped his cap to Mary, who astutely noted the diminutive size of the headless alcid.

While Dovekies are not unheard of in the waters off New Jersey, author/super-birder Kenn Kaufman describes their distribution thus, “Small numbers come as far south as New England waters in winter, rarely farther, but the vast majority remain farther north.” While there’s no way to say from whence this particular Dovekie came, or how it met its demise, it does seem likely that this bird is part of the overall influx of alcids into the northeast which was detailed in an earlier post.

The Long-tailed Duck found on the Cape, on the other hand, is a common winter resident around the Cape and islands, but does not commonly turn up on SEANET beaches. These northern breeders congregate in dense groups over the winter, and are a particularly vocal species. The one found by Mary Myers is a male; while some of the characteristic facial markings are somewhat obscured by sand and general bedragglement, the pink stripe on the bill is rather distinctive.

A rather livelier looking male Long-tailed Duck in winter plumage (photo by Michael Daniel Ho).

The SEANET blogger would like to point out that the photo shown here of the Long-Tailed Duck is by the talented photographer Michael Daniel Ho. Check out his other great bird photos at his website. Michael has been kind enough to grant SEANET permission to use his photos on the blog as an educational aid, and we are most grateful for that favor.

Finally, a note from the Department of Shameless Self-Promotion. After SEANET’s plea for blog visits to put us over the top on the Nature Blog Network stats, we actually dropped in our ranking! Is this a cosmic rebuke for making such an open plea? We hope not. We also want to thank blog reader Dawn Fine who tweeted about us on Twitter to help get the word out; we appreciate it, Dawn! And we humbly beseech the blogo-verse to forgive us our transgression and to raise our stats once again if it sees fit.





Dead bird Quiz answer

5 03 2009
Long-tailed Duck female

Long-tailed Duck female

Yesterday’s mangled feather ball is a female Long-tailed Duck. Perhaps you are wondering how one might determine this. The first things to note are the dark wings with lighter brown scalloping over the mantle. Additionally, there are extensive white areas, which would be visible on the belly and flanks of the intact bird. And finally, the feet have a bluish tint, admittedly difficult to appreciate from this photo, but present nonetheless.

The Long-tailed Duck winters in large groups off Nantucket, yet it is a surprisingly uncommon find out on volunteer beaches.  SEANET finds this puzzling, and includes it on our ever lengthening list of questions raised as your beach walk data accrue over the years. Other ducks that commonly overwinter off Cape Cod and the islands turn up very frequently on SEANET beaches (Common Eiders and White-winged Scoters, for instance.)

An intact, non-mangled Long-tailed Duck. Note the white over the flanks and the brown scalloping over the back.

An intact, non-mangled Long-tailed Duck. Note the white over the flanks and the brown scalloping over the back.

We will continue to ponder this and other such earth-shattering questions as we begin to work more with all your excellent reports. And thanks for taking photos like this that make identification as straightforward as it can possibly be…given the circumstances!





Name that dead bird II

24 11 2008

OK, so that first one was a warmup. Jack is correct, it is an Oldsquaw (also known as Long-Tailed Duck). Since that one was soooo easy, here’s a headless carcass. Try your hand at this one, found by Dennis Minsky (WB_39) on Cape Cod in November. Dennis’ identification on the card in the photo has been obscured so you have a chance to challenge yourself. Have at it!

mystery-bird