Mystery Bird: Carolina Wren, Thryothorus ludovicianus

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[Mystery bird] Carolina Wren, Thryothorus ludovicianus, photographed in an abandoned finch nest on the deck outside the home of one of my readers in Powder Springs, Georgia. [I will identify this bird for you in 48 hours]

Image: Rebecca Checkwood, 11 December 2009 [larger view].

Sony DSC-W7, 0.025 sec (1/40) f/2.8 7.9 mm.

Please name at least one field mark that supports your identification.

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This fool thinks we are looking at the back end of a very puffed up Carolina wren, because of the white spangles on the feathers above the very wrennish tail and the hints of rufous up front and the fact that the time and location make sense.

I'm prepared to be wrong, though.

I have been reading your blog for several months now and I just wanted to let you know that I think you are doing an amazing job. I really enjoy the Mystery Blog posts! I work for a science education company with the focus on reptiles and amphibians. We do an occasional bird watching event and this site has been very helpful to me. Thanks again!

The mystery bird might be a raptor, Accipiter gentilis - Northern Goshawk, which does not occur in Georgia. Hence, maybe the Red-tailed Hawk, which might be too big. So, final idea Black-billed Cuckoo.

Cheers
Dr.D.

I'm gonna say Carolina Wren, but then again I only really know about a dozen birds well enough to have any confidence. And related, similar, birds are going to throw me off. Might be a rare Lower Slobovian Miniature Mutant pea-hen for all I know. I just happen to have seen a Carolina Wren puffed up like that a while back while contemplating evicting a pair that had nested on my house. Didn't look exactly like that but if I squint my eyes just right the picture looks kind of like what I saw.

Identification of birds is pretty tough. In part because there are, IMHO, pretty wide variations between individuals and presentations. It would be handy if birds came with labels and hyperlinks to help with identification.

Could someone please point me in the direction of a good online bird identification program.

I've tried a few but even using birds I absolutely know, It's a dove for Christ's sake, I often can't get the identification to come up by selecting attributes offered. Seems that gray wasn't specific enough in one case and they wanted 'ocean-mist gray' or some such nonsense. And questions like 'length of beak' seem queer in that if I punch in that the beak is the same length as the head the right bird pops up but the beak is clearly not that long. I checked it with calipers on a photo of a profile. They must be measuring the head is some way I'm not familiar with. Cardinals pop up pretty well but then again how many red birds with a crest and black masks are there that hang around the SE USofA. Seems the programs are best when not needed and pretty useless when they are.

So often I'm stuck with: There is a bird on my porch. Flew right up to me and landed not three feet away. Q - What type? A - Ummm ... blue ... small ... with a bit of white on the wing while perching. Q - What type of bird???. A - Pretty. It was a very pretty bird ... Arrrgggg.

After trying a couple of online identification programs and reworking them multiple times I came up with the closest match being, wait for it, a bird that never comes within a thousand miles of my location ... D'oh! ... So I'm back to talking about the pretty little bird.

Maybe it's just me. I also have some difficulty with names and faces unless they do something remarkable or I spend a lot of time with them. Childhood trauma/brain damage I suspect. Troublesome, I once worked with a guy for a month on and off and still didn't know his name, but also handy. If I don't remember you every day is a 'new day'. He remarked that he liked me because 'I never held his mistakes against him'. It tends to throw off bullies and love bombers because they are trying to build up a reflexive sense of dread or obligation over time.

I think the solution, Art, is to take photos and send them to Grrl with "Here's a mystery bird for you to try on your readers" as the subject. Although it's a bit embarrassing if it's the same bird each time.

my thought was a wren as well, and the winter wren seems rather speckly...

I'm onboard with the Carolina Wren ID. I'm not sure I would have come up with it on my own, but checking it after pk1154's ID, I can see those light-colored rump speckles in Sibley's illustration of the bird in flight, and the barring on the tail certainly looks like a close match.

Although the size (abandoned finch nest) rules out any of the barred-tailed raptors, if this was about a thousand miles further West, we could almost argue for a Ferruginous Pygmy Owl (cactorumis subspecies in southern Arizona, ridgwayi in southern Texas), however we're out of range and would expect a few other differences from the image above (alternating wider bars of tawny/dark brown on the tail, not brown/black as above, etc.), so all we are really left with are wrens:

both the Winter and Sedge Wrens should show much shorter tails; the Rock Wren (greyer) is out of range; although out of range according to Sibley but not according to the University of Georgia Museum of Natural History, the Bewick's should show some white barring on the tail and outer feathers; leaving us with House (Troglodytes aedon), Carolina (Thryothorus ludovicianus), or Marsh (Cistothorus palustris)...

I'm finding the tail troubling though, alternating between eliminating all three in turn yet returning to one or the other when I find variations within species concerning color and barring- all the photos I can find tend to show more of a weathered and faded tail so perhaps this is just a "fresh" look...

I think the white "speckling" is somewhat of a red-herring and not a usual part of this species' coloring- we often only have the "typical" image of the bird provided in guides and not so much age-range or subspecies differences, anomalous coloring, or, as I think in this case, birds in molt- I have seen this "snowflake" spotting on a Carolina Wren in molt, and so I am tending towards that species: Carolina Wren, Thryothorus ludovicianus ludovicianus (the eastern US subspecies found from New England south to Texas and northern Florida)... but again, the tail is not quite right for me!

By David Hilmy (not verified) on 17 Dec 2009 #permalink

I think we are looking at 2 very chilly Carolina Wrens. The second bird can be seen to the right of the main bird. It's quite possible there is a third one underneath too!

Field marks - The tail barring is telling me, wren. The spots look like Carolina Wren. When they puff up their feathers, the stripes appear to turn into spots.

If this is indeed a Carolina Wren, I'm a little concerned about the richness of the brown in the tail, and of course the "snowflake" look which may be, as I have understood previously, the result of molt, yet as articulated below, the annual molt is usually late Summer and wouldn't necessarily show this late in the year (Paul?)...

From the online version of the Life Histories of Familiar North American Birds I find the following:

Soon after hatching the young wrens are scantily decorated with slate-colored down; the juvenal plumage develops rapidly and they are well clothed by the time they leave the nest. In the juvenal plumage young birds look much like the adults, but they are paler in color and the plumage is softer in texture; the wing coverts are tipped with buffy white, the superciliary stripe is less clearly white, the under parts are whiter, and there is some dusky barring or mottling on the flanks and sides of the head.

The first winter plumage is acquired by a partial postjuvenal molt in August and September, involving the contour plumage, the wing coverts, and the tail, but not the rest of the wings. This plumage is darker and richer in color than the juvenal plumage, chestnut or Vandyke brown above and deep cinnamon below, with white tips on the wing coverts and a whiter superciliary stripe, young and old becoming practically indistinguishable.

Adults have a complete postnuptial molt in August and September; after this molt, in fresh fall plumage, all the colors are brighter and richer than in the worn and faded plumage seen in spring. The sexes are alike in all plumages.

I understand that the Floridian subspecies miamensis is the darkest and richest of all Carolina Wrens, recorded from about 30° latitude (Jacksonville) and then South, but I wonder if there is some Goergian variation that is playing a part in the richness of the brown in our photo?

Someone please put me out of my Quasimodoesque misery... the tail, the tail...!

By David Hilmy (not verified) on 17 Dec 2009 #permalink

I'll agree with Carolina Wren, although the spotting surprised me at first. Upon closer inspection, it appears that many of the spots are on fluffed-up wing coverts, and that's exactly where a Carolina should have them. I don't find the tail to be unusual for Carolina -- it fits well with the scattering of photos I have -- all winter birds. I don't know the species well enough to comment on age, though.

David, the confusion regarding Bewick's Wren has a bit of history to it. The species used to occur almost to the East Coast. It's disappearance in the East over the last 30 years or so is generally considered to be rather mysterious. Here in Illinois, it's now a very rare bird -- there is one town in western Illinois that hosted a couple of pairs until just a couple of years ago, and I've only ever seen one in the state. So the Georgia Museum simply hasn't updated anything recently. I suspect that whatever organisation that maintains records in Georgia has Bewick's on their review list, and probably lists the species as extirpated.

Good point on the Bewick's, Paul, I'll look into what Georgia considers current, however with 16 subspecies recorded for it, discussion about it's conspecificity with the Carolina (itself having at least 7 subspecies), and also with the Socorro Wren, Troglodytes sissonii, we come back as we always do to what exactly constitutes a "species" and I feel that increasingly Ernst Mayr's argument simply doesn't cover all the bases anymore...

By David Hilmy (not verified) on 17 Dec 2009 #permalink

No has commented on the wren's nest. My Carolina Wren built a dome and my House Wren built a dish, so since the tail has fine bars as well I vote for House Wren.

By Michelle Scholz (not verified) on 18 Dec 2009 #permalink

Michelle -- you're right that this isn't the right sort of nest for Carolina -- it's the wrong sort for House Wren as well. But this photo was taken in December, when the birds aren't using a nest for it's usual purpose, and the caption points out that the nest was originally built by House Finches.