Long-billed Dowitcher

[James Salywoda]

As this post presents interesting ID issues, I have copied James' thread from Avian. Thanks for posting this interesting image James.

artie

Long-billed Dowitcher
SoCal

Taken a few days ago as I like the wing position captured on this little bird.

Nikon D300s AFS 600 F4

1/1600 F6.3 ISO 400

Thanks For looking

Jim

[Gyorgy Szimuly]

Very cool and very rare flight image in this quality.
Well done. Perfect wing position and light. A nominee for my book ;)

Szimi

[Arthur Morris]

Love the underwing detail. The bird's bill could have used a bath, but heck, they are dowitchers. Did you hear this bird call? If not, what was the basis of the ID?

[James Salywoda]

Love the underwing detail. The bird's bill could have used a bath, but heck, they are dowitchers. Did you hear this bird call? If not, what was the basis of the ID?

Thanks all for comments as far as ID goes I really wasn't a 100% sure but I thought it was a
Long-billed Dowitcher.

I confirmed it with Szimi and the barred tail feathers were the markings that helped verify it as a Long- billed Dowitcher.

[Arthur Morris]

Thanks all for comments as far as ID goes I really wasn't a 100% sure but I thought it was a Long-billed Dowitcher. I confirmed it with Szimi and the barred tail feathers were the markings that helped verify it as a Long- billed Dowitcher.

Thanks James for getting back to me. Separating long-billed from short-billed dow in non-breeding or winter plumage by plumage characteristics alone is difficult for all but the most skilled field observers. Both species have barred tail feathers; it is the differences in the width of the blacks as compared to the width of the whites that indicates one species of the other. But those differences can be most difficult to discern either in the field or in a photograph. I was surprised that I found no mention of the differences in tail-barring in "The Shorebird Guide" (O'Brien, Crossley, and Karlson).

There is much overlap in bill length in the two species with the short bills of male short-billeds and the huge pig-stickers of female long-billeds making ID on bill length easy at times.

The best bet for in the field ID of these two (who differ greatly in the timing of migration and plumage sequences varies greatly) is best done by voice. Listen for the sharp single keeek or as described in the above-mentioned book, peeep. Shore-billeds call is a rolling, whistled three-noted affair that might be described as koo tu-tu.

I would not want to ID this bird based on the bill (though some might be able to do so) but the smooth gray throat and the seemingly heavy barring on the flanks, and yes, the tail barring with the whites and blacks equal in width would seem to indicate long-billed.

More on the tail-barring from "Shorebirds" by Hayman, Marchant, and Prater: non-breeding short-billed may lack barring on the tail. In long-billed, the width of the dark bars on the tail is equal to or (usually) greater than the width of the white bars. In short billeds, the width of the white bars is equal to or (usually) greater than the width of the dark bars.

Last complication: though I cannot tell from this image, there is a chance that the bird is a juvenile Long-billed Dowitcher (rather than a non-breeding/winter plumage adult of either species....)

It is always best to get the ID from the calls. :) I am copying this thread to the Avian ID Forum.

[Arthur Morris]

James, please let us know exactly where you created this image.

[James Salywoda]

James, please let us know exactly where you created this image.

Not a problem Artie this was taken at the Bolsa Chica Ecological Reserve H.B

Here is a shot wings down that may help:)

[Arthur Morris]

Thanks again James. Long-billed is the more likely of the two inland so the location tells us nothing.... Kevin Karlson has a good column on separating these two species in winter plumage in the current (NO/DEC 2009) issue of WildBird Magazine.

Thanks also for the wings-down image. I have little experience aging shorebirds in flight but--with the neat feather patterns and the brownish tones--this looks like a juvenile in fairly fresh plumage. If that is the case, the bird must be a Long-billed Dowitcher based on plumage and date. Juvenile short-billed come through in mid-AUG and by early OCT have molted to first winter plumage.

That said the bill of this bird looks perfect for short-billed: rather deep at the base plus a downward kink of the distal half of the bill. The lack of any dense barring on the flanks is also suggestive of short-billed.

Final answer: I have no clue at all.

I will try to get Richard Crossley, Kevin Karlson, and or Julian Hough to take a peek at this one. I would not be shocked if they disagree....

[John Chardine]

For what it's worth here is a Short-billed Dowitcher seen at Sackville, NB, this September. Note the bill and the tail.

[Arthur Morris]

Thanks John,

OK. Does anyone want to take a stab at aging this bird? Come on, be brave. Remember the rules: splotchy = adult; evenly patterned = juvenile.

[Ilija Dukovski]

John's bird is definitely adult.

Bird on #7 I'd say juv.
NOW, IF this is juv. we should take a good look at the tertials.
In Long-billed they are solid dark with VERY narrow edge.
In Short-billed they are broad edged with PALE stripe running
in the middle and few bars also possible.
This is exactly what I see on the image on #7.
Tail barring might in juv. case be irrelevant.
Also I believe in adults tail patterns can overlap between the two species.
Not sure about this though.

If juv. this could be SB

[Arthur Morris]

Hi Ilija,

re:

John's bird is definitely adult.

John's bird if definitely a worn juvenile. 100%. Adult short-billed would never look so bright above or be so well marked in September. And the feather patterns of the juvies are nothing like that of the adults.

Bird on #7 I'd say juv.

I agree but am not 100% sure.

NOW, IF this is juv. we should take a good look at the tertials.
In Long-billed they are solid dark with VERY narrow edge.
In Short-billed they are broad edged with PALE stripe running
in the middle and few bars also possible.
This is exactly what I see on the image on #7.

With the rear view I am not even sure where the tertials are, but if this bird is a juvie then it is not a short-billed. Period. Even worn short-billeds are much more brightly marked than this bird.

If juv. this could be SB

If this bird is a juvie then it must be a long-billed. You need to go back and study more :) :) :)

[Arthur Morris]

Do see this one: http://www.birdphotographers.net/for...ad.php?t=47380

[Ilija Dukovski]

John's bird if definitely a worn juvenile. 100%. Adult short-billed would never look so bright above or be so well marked in September. And the feather patterns of the juvies are nothing like that of the adults.

Oops, big time :( I was looking at the scapulars and they are solid dark with pale edges.
In juv. SB I expected patterned scapular with V-shaped light pattern in the center.
Also, the tertials are barred, I expected stripe along the length of the feather.
So... This is all true for the atlantic race of SB (griseus). I hit the books and realized that the pacific
race (caurinus) juvs. have solid dark scapulars, just like John's picture.
Also the tertials in the pacific race are more irregular and barred.
Not sure about the interior (hendersoni) race though. If you know please let me know too.

Is this bird a rare occurence of the pacific race in the east, or is it the inland race?
Even the inland race should be rare in NB Canada, right?

Cheers,

PS September bird:o

[John Chardine]

Here's another dowitcher from Sackville this September. Isn't this fun!

BTW the dark feathers on the bird's back staring to the right of the mid-back are the tertials.

I got a bit confused with the comments above (#10). Is the bird I posted (#7) a LBDO? If so I'd be thrilled. Also this bird here?

[Arthur Morris]

Hi John,

re:

Here's another dowitcher from Sackville this September. Isn't this fun!

Yes. Much more fun than you know what!

BTW the dark feathers on the bird's back staring to the right of the mid-back are the tertials.

Please check out the posted image here and let me know if this info is correct:

I believe that the feathers with the red dots are scapulars not tertials.....

I am 99.99% sure that the longer feathers with the green dots are tertials.

And that the two with the blue dots are primaries.

Please confirm or refute :)

I got a bit confused with the comments above (#10).

In Pane #10 I was hoping to elicit the fact that the bird in Pane #9 was a juvenile as there are no splotchy feathers, no mixture of worn adult and fresher winter feathers.... But that attempt failed :)

Is the bird I posted (#7) a LBDO? If so I'd be thrilled.

As I said above, I am totally confused by the bird in Pane #7 (and therefore the same bird in Pane #1....) My latest thought on that bird is that it might be a first winter short-billed. The tail is neither here nor there and the bill shape says short-billed.....

Also this bird here?

The bird shown in your two photographs, seemingly the same bird, in Panes #9 and 15, is a worn juvenile Short-billed Dowitcher. First off, the bird is an obvious worn juvenile. And the tail with the white bands wider than the dark, screams SBDOW. Once I hear back from you on the feather tracts, I will let you know the 2nd main reason.

[Arthur Morris]

ps: I am realizing that I might be totally wrong with the colored dots above....

[Phil Battley]

Hi Artie,

Both the green and blue dots are tertials. The primaries are just visible beyond the longest tertial. The red dotted feathers are indeed scapulars, as are the other buffy feathers to their left. The white-fringed feathers are the wing coverts. The larger buffy feather to the left of the lower blue dot seems also to be a greater wing covert.

Cheers, Phil

[John Chardine]

OK so I think we all disagree! The flight feathers- primaries- are the anterior green and blue dots which end near the tail (remember there are 10 of these so they will take up quite a bit of space, even though they overlap a lot). A field mark for some species is whether these primaries reach past the tail or not. The red dots and maybe the posterior green dot are I think the tertials. Here's a sketch from http://www.infovisual.info/02/057_en.html (with I hope the appropriate attribution).

Mod note- ignore the text! Just look at the picture!

[Phil Battley]

John, look at some flight shots of dowitchers and you will see that the primaries are plain brown feathers. On a folded wing you hardly see the primaries, and it's the tertials that cover them. The curve on the tertials shows they are not structurally strong feathers too. Take a look at Richard Chandler's Shorebirds book. He has good illustrations showing the tertials overlaying the primaries in standing shorebirds. I stand by my colour-coding claim. :-)

Phil

[Ilija Dukovski]

I think image #9 shows both the tertials(patterned) and primaries (non-patterned) below the tertials.
We could discuss that one too.

[John Chardine]

Because I made a right b_a_ll_s-up of the last attempt, and to reduce confusion, here are the feather sets I think we are seeing here. Boy I hope I'm close to having this right now!

[Phil Battley]

Hey John, shift everything bar the primaries down one, and drop the secondaries. You just don't see them under the wing coverts and tertials generally. What you have circled are: mantle / scapulars / tertials / primaries. In the hand, the scapulars attach to the shoulder and the tertials to the wing, so moving the wing reveals the difference (though just where the ~25 scaps start is not often clear).

Lovely shot!

Phil

[John Chardine]

I think I've got it Phil! Thanks.

[Bruce Enns]

Very educational...and fairly confusing! I think I need a slow movie of the wing from the top folding closed. Anyone got their 7D ready for some 60 fps video?

Thanks Phil, John and Artie!

[Arthur Morris]

My original purpose for posing the question about the feather tracts is to point out that identifying them correctly can be quite difficult.

I got this e-mail from Richard Crossley one of the authors of the highly detailed "The Shorebird Guide:"

Red - scapulars. Green and upper blue all tertials. Lower blue should be a secondary of which tertials are just an extension of - it would be easier in the hand. Very confusing! RC

Therefore, we can pretty much say for sure that the red-dotted feathers in Pane #16 are indeed scapulars and that at least the two green-dotted and (at least) the upper blue-dotted feathers are tertials.

The tertials of juvie short-billed almost always (as this bird shows clearly) have internal orangish markings. The tertials of juvie long-billeds are always just fringed with no internal markings.

See here for Bruce Enns' great juvie long-billed showing the plain tertials with no internal markings:

http://www.birdphotographers.net/for...ad.php?t=47380

[Arthur Morris]

Well, so much for total agreement. I got this from Julian Hough who is superb:

 A.. Think I got it right... red = rear scaps upper green dot = think this is a sub scapular - usually difficult to see since often covered by rear scaps lower green dot = uppermost tertial blue dots = both tertials hope all is well..

J

[Ilija Dukovski]

My understanding is that tertials are the 3 inner secondaries that by definition cover the secondaries when the wing is folded.
So if the wing is folded and you can see the feather it is either primary or tertiary. The feathers above the 3 tertiaries would
then be lower scapulars. What do you think? Does this make sense?

[Ilija Dukovski]

I just realized that in songbirds you can see the edges of the secondaries in a folded wing,
but only the edges, the 3 tertials are fully visible in songbirds too.
Not relevant for shorebirds though. In shorebirds I think no secondaries are visible in a folded wing.

[Arthur Morris]

My understanding is that tertials are the 3 inner secondaries that by definition cover the secondaries when the wing is folded.
So if the wing is folded and you can see the feather it is either primary or tertiary. The feathers above the 3 tertiaries would
then be lower scapulars. What do you think? Does this make sense?

I think that you need to draw a picture with colored dots; I ahve no clue what you are talkling about.

Another thought: sorting out the feather tracts on a flying, running, standing, feeding, preening, or even sleeping birds is a lot harder than sorting them out on a diagram in a book. :) :) :)

[Ilija Dukovski]

I think that you need to draw a picture with colored dots; I ahve no clue what you are talkling about.

Will do later today. I think there's a difference in the definition of tertials in songbirds and in the rest which makes things
very confusing.

Another thought: sorting out the feather tracts on a flying, running, standing, feeding, preening, or even sleeping birds is a lot harder than sorting them out on a diagram in a book. :) :) :)

Of course, but we need to sort out the books and the definition of tertials to get to the bottom of this. :)

[Chris Sloan]

There is no difference in tertials for songbirds and tertials for other birds. The confusion stems from the fact that in most shorebirds the tertials on a perched bird entirely or mostly cover the primaries, whereas in most perched songbirds the primaries are more exposed. This is by design; the tertials are broad and sturdy and they serve to protect the more critical flight feathers from exposure to the harsher elements to which birds of open/coastal environments are generally exposed.

[Phil Battley]

To solve this, could someone please mist-net a dowitcher, and count the tertials for us.

Here's what Danny Rogers (a very experienced moultee from Australia) says in "Shorebirds of Australia" about tertials:

"Strictly speaking, the tertials are modified innermost secondaries but in moult studies and for identification purposes, it is conventional to restrict the term secondaries to those ten outer remiges of the ulna, which are shaped essentially like flight feathers. In practice, the difference in shape between the innermost secondary and outermost tertial is not very clear and there is not common agreement about which feather is the outermost tertial."

Danny worked for many years preparing plumage and moult descriptions of shorebirds and other birds for the Handbook of Australian, NZ and Antarctic Birds. I defer to him on all matters relating to plumage!

Phil

[Arthur Morris]

As I inferred above IDing feather tracts on a diagram or a bird in hand is much, much easier than on a living bird regardless of posture or behavior.

[Ilija Dukovski]

"Strictly speaking, the tertials are modified innermost secondaries but in moult studies and for identification purposes, it is conventional to restrict the term secondaries to those ten outer remiges of the ulna, which are shaped essentially like flight feathers. In practice, the difference in shape between the innermost secondary and outermost tertial is not very clear and there is not common agreement about which feather is the outermost tertial."

This adds light to the problem. There is NO agreement to what is a tertial and what not!
On the image from wikipedia
http://en.wikipedia.org/wiki/Flight_feather
(there's similar in Gill and other places so I think it is credible) the secondaries are defined as remiges attached to the ulna, and tertials are remiges attached to the humerus. But as Phil and Artie pointed out, sometimes it is not clear what is innermost secondary and what outermost tertial. Therefore both Arties friends are right. We can have tertials and elongated secondaries, it is a matter what convention you follow.

Now I'm not sure how credible is this quote from wikipedia but if true, things are even more complicated with songbirds:

" Tertials are connected to the humerus in some species. These elongated "true" tertials act as a protective cover for all or part of the folded primaries and secondaries, and do not qualify as flight feathers as such.^[11] However, many authorities use the term tertials to refer to the shorter, more symmetrical innermost secondaries of passerines (which perform the same function as true tertials) in an effort to distinguish them from the other secondaries."

That means we have another definition of tertials: Any remiges (regardless whether they are attached to the humerus or ulna) that cover the rest of secondaries in a folded wing are called tertials. Technically they can be secondaries, but due to their function they are called tertials anyway, which is what Chris mentioned above.

I can imagine the confusion if you learned this definition first and then try to apply to other birds and vice-versa.

So at the end of the day no one and everyone is right simply because there is no good agreement on
how to distinguish between tertials and secondaries.
I hope I didn't bore you to death, but I think all of this is a bit more clear to me now.:)

[Phil Battley]

I'll have to do a dissection some time and figure this one out. It won't be on a dowitcher, but it could be done.

Phil

[Danny Rogers]

I can't agree with the Wikipedia drawing. The feathers attached to the humerus are humerals, not tertials. Shorebirds don't have humerals (at least, if they have any, they are so small as to be invisible in photos), and their tertials are attached to the base of the ulna. They've usually got 4 or five tertials per wing. Most passerines only have three tertials per wing.

Humerals are better developed in some other groups of birds, but they never shield the secondaries in the way that tertials do, and they can't be seen when the wing is folded. Great Crested Grebes are a nice example if you happen to see them well in flight, with white secondaries and humerals contrasting with dark tertials.

[John Chardine]

Thanks Danny (and welcome to BPN!). I think I can count 5 tertials in the dowitcher in #9 above. Does that seem correct?

[Danny Rogers]

Yes, I also think I see five tertials on the left wing. The outer tertial is mostly hidden, and it seems to be completely hidden on the right wing.

[Ilija Dukovski]

I can't agree with the Wikipedia drawing. The feathers attached to the humerus are humerals, not tertials. Shorebirds don't have humerals (at least, if they have any, they are so small as to be invisible in photos), and their tertials are attached to the base of the ulna. They've usually got 4 or five tertials per wing. Most passerines only have three tertials per wing.

Humerals are better developed in some other groups of birds, but they never shield the secondaries in the way that tertials do, and they can't be seen when the wing is folded. Great Crested Grebes are a nice example if you happen to see them well in flight, with white secondaries and humerals contrasting with dark tertials.

Hi Danny,

Welcome, it is great to have diversity of oppinions here. I didn't know they are called humerals, thanks for the info.
Can you point out the sub-scapulars on image #9. I'm quite confused what they would be on that image.

Thanks, Ilija

[Ilija Dukovski]

OK I think I finally got it. Here's a paper in the Auk,
"The trouble with tertials" by Scott Hickman.


http://caliber.ucpress.net/doi/abs/1.../auk.2008.2408

No wonder the confusion here. The article in essence states
that the confusion is present in the ornithological literature as well
and he proposes a strict definition of tertials. Not sure if it is
currently widely accepted or not. The year is 2008 so the debate
might be still going on.

Cheers,

[Danny Rogers]

On the left wing of the bird in photo 9, just above the shortest tertial, I can see small bits of three plain dark feathers with crisp white edges. I think those are subscapulars, though I'm not 100% sure. Subscapulars are funny feathers - usually hidden, and when they are exposed, it's often because the bird is a bit dissevelled and feathers aren't aligned in a completely normal way.

[Ilija Dukovski]

On the left wing of the bird in photo 9, just above the shortest tertial, I can see small bits of three plain dark feathers with crisp white edges. I think those are subscapulars, though I'm not 100% sure. Subscapulars are funny feathers - usually hidden, and when they are exposed, it's often because the bird is a bit dissevelled and feathers aren't aligned in a completely normal way.

Great, thank you. It makes sense.

[Julian Hough]

Further to my note to Artie, the green and blue dots are tertials and the red dots are rear scapulars.

The flying bird in question in Panes #1 and #7 is, I believe,a Short-billed Dowitcher moulting from juvenile into first-basic plumage. It still has retained juvenile wingcoverts and primaries but seems to have replaced most of its juvenile mantle and scapular feathers. There is one remaining feather visible on the downstroke shot which shows the paler, internal "tiger-stripe" markings characteristic of Short-billed Dowitcher.

SBDO moult later than LBDO and thus would be expected to be further along in their transition from juvenile to basic plumage - as is shown by this individual. LBDO at this time of year are largely still in juvenile plumage, albeit with the exception of a few grey, adult-like basic feathers appearing in the scapulars.

Also, in my humble opinion, the bill length and shape and the length of the legs (judged from the relatively short foot projection beyond the tail) are pro-SBDO as is the lack of a strong lower orbital ring and a lack of a dark-hooded look typical of Long-billed.

Hope it's a SBDO or I'll have to re-take dowitcher class!

best,

Julian

ps: I hav attached Julian's mock-up photo here. I am hoping that Julian will be joining us here; he is a world class expert on shorebirds and lots of other species too. And also a pretty good photographer. The Brits are just too good....

[John Chardine]

Thanks for the detail Julian and welcome to BPN!

[Ilija Dukovski]

Great, thank you Julian and welcome,
would you like to comment on what sub-species
is the SBDO in #9. I'd really like to know that.

Cheers,

[Julian Hough]

ILIJA,

I have to assume it's a griseus if it's taken in the east -the default race occurring along the eastern Atlantic seabord. The only other subspecies would be the "inland" race, hendersonii, which occurs regularly in the east. In general, identifying juvenile-plumaged dowitchers to species is difficult if not impossible.

I have seen some very bright juveniles at Jamaica Bay that are very richly colored below compared to what I would call typical griseus and these may have been juvenile hendersonii, but I really don't know for sure.

Hope this helps..

Best,

J

[John Chardine]

ILIJA,

I have to assume it's a griseus if it's taken in the east -the default race occurring along the eastern Atlantic seabord. The only other subspecies would be the "inland" race, hendersonii, which occurs regularly in the east. In general, identifying juvenile-plumaged dowitchers to species is difficult if not impossible.

I have seen some very bright juveniles at Jamaica Bay that are very richly colored below compared to what I would call typical griseus and these may have been juvenile hendersonii, but I really don't know for sure.

Hope this helps..

Best,

J

Julian- do you mean sub-species here, or is speciation really difficult?

[Bruce Enns]

Hi Julian and welcome...thanks very much for the info. If you have a minute, I would really appreciate if you could have a look at frame #20 on the other dowitcher ID thread ( http://www.birdphotographers.net/for...ad.php?t=47380 ), and check my feather IDs.

Cheers!
Bruce

[Arthur Morris]

In 25 years many of them at JBWR I have never seen an adult Baird's anywhere on this planet (or others). David Mizrahi who helped me with the Manmet Shorebird Survey that I did for 8 seasons found one on the East Pond in late July of 19??. And I have seen only a handful of juvies. Once you see one juvie Baird's future recognition is instantaneous.

For those of you who did not see my comments on Julian's skills and knowledge elsewhere I can only say that he is the real deal. Ask him about the Brit's eating me out of house and home when they stopped by my and Elaine's apartment in Howard Beach, NY on the way to JFK in the mid-eighties. Julian is one of only a few who are still in my life who had the pleasure of meeting my late wife and loving her as everyone who met here and saw here smile did.