American Golden Plover at Breydon

[Brian S]

There has yet to be any discussion on surfbirds about this bird, though I note the chattering classes on BF have dealt with it. It was not until Lee Gregory's photo was posted on surfbirds that it's identity was really sorted out.

I went to see it this morning, and though it was misty the plover showed quite well and I took the images below - sorry about the quality, but they were taken as stills on my video (it was not that close).

It has some obvious features:-

There are two ages of scapulars and coverts: the new black-centred and broadly golden-fringed scaps are fresh and quite short (not fully grown), and contrast with the older faded and off white-edged lower scaps; the new coverts and tertials are similar, with large golden notches contrasting with the narrower, pale edges of the older feathers.
The left wing is longer than the right wing, and hangs a little showing the white shaft; it also appears as if there is a larger gap between the longest primary and the next - perhaps there is a broken feather. On the right wing the primaries are evenly spaced, but certainly look shorter. In my notes, I would guess that the extension o the right wing beyond the tail tip is 10-12mm, but 4-5mm longer on the left wing (the extension is equal to the length of the bill back to the lores), and such an extension is pretty typical of AGP.
There are some new dark grey feathers coming through on the breast sides.
The crown is dark, the bill is quite slim.


Brian S

[Brian S]

Last couple of images

Brian S

[Josh Jones]

Nice pics Brian. The newer pics emerging show this to be a clear American Golden Plover (after the inconclusive pics initially)... very bright individual for so early on! For example, the two recent Spanish birds were much greyer (which is perhaps more of what you would expect).

Hopefully this bird lingers a couple more days as I'm keen to see it myself!

Josh

[JanJ]

Appart from plumage features and such, structurally it fits dominica better.
The long rear is clearly showing in these images:

http://birds-britishbirder.blogspot.com/

In fulva the rear looks shorter, cut of.

JanJ

[Sandgrouse]

Hi Brian,

At last some better pictures of the Lesser Golden Plover which demonstrate that it is a Pacific Golden Plover and not an American Golden Plover.

You seem to be one of the few people that have picked up on the drooping, damaged left wing which causes this bird to have a much longer primary extension than would normally be the case. Examination of photographs indicates that the outer primary on the left wing is bent outwards and has reset at an angle, not only causing the primary to be longer than it actually is but also creating the impression of a missing primary. There may well be a missing primary but it is very difficult to be certain about this on the left wing. Therefore any attempt to measure the primary extension based on the left wing is invalid - see photograph below showing the bent outer primary on the left wing.

The primaries of the right wing do not extend as far beyond the tail as the left wing. I estimate that the damaged left wing primary is 40% longer than the right wing primary tips and thus the primary extension of the right wing falls well within Pacific Golden Plover range.

Using your photographs above, the bird is clearly well into its pre-breeding moult but the tertials do not appear to be fully grown. On the left wing three of the four tertials are clearly visible with the outer tertial about 60% of the length of the middle tertial and the inner tertial also shorter than the middle tertial. On the right wing only two tertials are clearly visible though the third (inner tertial) may just be appearing. The middle tertial is now beginning to narrow towards the tip (a week ago this was not so) and it is getting close to being fully grown. However, the tertials on the right wing are already very close to the tip of the fourth primary and if they grow further there will be a primary projection of only three primaries. This is speculation of course but reinforces the following warning:-

“The best character is the number of exposed primaries past the folded tertials ……………. We do not advocate using this distinction on molting birds that are missing tertials” (Dunn et. al. 1987 Field identification of forms of Lesser Golden Plover. Proceedings of the Fourth International Identification Meeting. 28-33. Eilat, Israel)

The fact that the Breydon bird is well into the pre-breeding moult cycle is very important.

The post breeding autumn moult of dominica is much later than fulva and is not completed by 1st/2nd calendar year birds until well into February at least, as typified by this photograph from Israel of a dominica still in heavy primary moult on 24 January 2009

http://www.israbirding.com/israelbirdsforum/forum_entry.php?id=1028&page=2&category=0&order=time

BWP states that the post breeding moult of fulva starts on the breeding grounds from July but then primary moult is arrested until they reach the wintering grounds and continues from September to complete from late November to late January. American Golden Plover only start the primary moult when they reach the wintering grounds and moult at least a month later than fulva from September to February. So dominica are about a month behind fulva in their moult cycles and this also applies to the pre-breeding moult with fulva moulting between late February/early March to April and dominica between late March/early April to May and although the primaries are not moulted, some fulva apparently moult some of the tail and they both moult some or all the tertials, scapulars, mantle, back., etc (BWP). Sorry about the long-winded explanation but the important point here is that in early April when the Breydon plover was first found it was clearly well advanced with its pre-breeding moult and it is too early for American Golden Plover to be so advanced. This is clearly illustrated by images of American Golden Plover in April:-

Firstly an American Golden Plover in Louisiana on 4 April 2004 still with most of its older feathers, in particular old tertials, scapulars, mainly older mantle feathers etc:-

http://homeport.tcs.tulane.edu/%7Edanny/gopl.JPG

Another very worn dominica with few signs of the pre-breeding moult having started, at Okolona, Chickasaw County, 3 April 2005:-

http://www.msstate.edu/org/mos/Images/American%20Golden-Plover.JPG

And yet another dominica in Ireland on 16 April 2007:-

http://www.birdsireland.com/images/2007/april/agp03.jpg

On the other hand fulva are well into their moult from March as shown by this bird in Australia on 15 March 2009:-

http://farm4.static.flickr.com/3457/3358000053_f80e92f984.jpg

In April the 2nd calendar year fulva behind the adult in summer plumage shows how bright they can be in Hong Kong:-

http://www.oceanwanderers.com/PacGoldPlov.1.JPG

Note also on the non-breeding fulva in Hong Kong, the long primary extension and shorter primary projection from the tertials though they still might be growing. It is not possible to count the exposed primaries on this photograph.

Two important things are very obvious from these photographs, one is that the timing of moult in early April shows that the Breydon bird is a Pacific Golden Plover but secondly American Golden Plover in non-breeding plumage at this time of the year (early to mid April) is a very grey bird whereas non-breeding Pacific Golden Plover have extensive golden fringes to the mantle and back. There is no hint of extensive yellow or golden fringes on non-breeding plumaged American Golden Plover in April.

Also it may be worth just showing this fulva from Bahrain in March which is probably just starting its moult with a white face:-

http://www.hawar-islands.com/blog/media/blogs/obs/pacificgoldenplover.jpg

Here is the photograph of the Breydon Pacific Golden Plover showing the damaged outer primary on the left wing with acknowledgement to the photographer Dave Appleton for allowing me to use it. For additional photographs taken by Dave Appleton please visit:-

http://www.gobirding.eu/Diary/Diary.html

Part 2 follows.

Andrew Grieve

[Sandgrouse]

One other almost diagnostic feature and an additional feature that strongly suggest that the Breydon plover is a Pacific Golden Plover are the short outer primary and the long unfeathered tibia respectively.

It appears that on fulva the outer primary is equal to or shorter than the next inner primary ie counting the outer primary as primary number 10, the 10th primary in many cases is shorter than the 9th primary. There are no photographs of dominica showing this feature, all dominica have a longer 10th primary than the 9th. Reading BWP, it seems they allude to this in the account for dominica when detailing fulva but then they appear to get the 9th and 10th primary mixed up.

Photographs to demonstrate this are for dominica:-

American Golden Plover first calendar year on Azores October 2007
http://www.birdwatch.co.uk/website/images/stories/galleries/Public_ID_PacificGoldenPlover/viewsize/AmericanGoldenPloverjuvCorv.jpg

http://www.kennewcombe.com/goldenplover.html

http://www.nature-shetland.co.uk/naturelatest/pics/American%20Goldie%202%20Sandwick%20Sep%202003.JPG

The latter bird is from the Shetlands.

For comparison here are fulva, of which two birds clearly show a shorter outer primary but the third is more indeterminate, from Singapore:-

http://3.bp.blogspot.com/__Dq5_ABpFrs/R7mSLxrUfCI/AAAAAAAAB1A/-MwoEpYt5k0/s1600-h/Pacific+Golden+Plover_Changi+Cove_170208_IMG_9822. jpg

Regarding this feature on the Breydon Plover, the left wing with its damaged primary is obviously of no use but the right wing appears normal and there are some good pictures showing the shorter 10th which are included at the end of this message.

Another oft quoted distinction between fulva and dominica is leg length with fulva being quoted as having longer legs creating a more lanky appearance. In fact there is a complete overlap in tarsus length measurements between the two species BUT there is a difference in the length of the bare area of the tibia. I suspect that the tibia is longer on fulva but it is not possible to measure on a live bird as the body feathers cover the upper part of tibia. There are measurements of the bare area of the tibia (Johnson, O.W. & Johnson, P.M. 2004. Morphometric features of Pacific and American Golden-Plovers with comments on field identification. Wader Study Group Bulletin 103: 42-49):-

--------------------> American Golden Plover ---> Pacific Golden Plover

Tarsus length ---------> 42.9 to 50.4 ------------> 44.1 to 47.6

Tibia unfeathered ------> 14.8 to 21.2 ------------> 17.6 to 24.1

Mean length of the unfeathered tibia differed significantly between the two plovers (t = 7.82, P = <0.0001, df = 58) with fulva averaging nearly 4 mm longer than dominica.

The Breydon bird shows a long bare tibia and looks long-legged which is another plus for Pacific Golden Plover.

There are many other features that point to the Breydon bird being a Pacific Golden Plover. In flight and from a distance it looks a typically dark brown fulva – a combination of the golden fringes to the mantle and back and dark grey feather centres – in dominica the feather centres are blacker and the fringes are whiter and this combination creates a dark grey plumaged bird at a distance. A photograph is included below of the bird in flight at a distance showing this dark brown appearance.

The bill looks longer, thicker and broader at the base, said to be another feature of fulva.

There are other features too numerous to mention, but most importantly the bird has been heard to call. The call heard was described at sounding like a Spotted Redshank and was transcribed as a sharp “chee-wee” (per Peter Allard et al). This is almost diagnostic of Pacific Golden Plover and for those that are experienced with the call of both birds, they say it is diagnostic, though American Golden Plover may have a similar but not quite the same call.

Summary

The damaged outer primary on the left wing invalidates any attempts to measure primary extension.

Extensive golden fringes to the mantle and back on non-breeding birds are only shown by Pacific Golden Plover. American Golden Plover in non-breeding plumage at this time of the year are very much greyer with mainly white fringes – as further demonstrated in this document:-

http://www.kevinkarlsonphotography.com/pdf/SpringShorebirds_WB2005.pdf

The timing of the pre-breeding moult sequence fits Pacific Golden Plover, American Golden Plover moults later and as the tertials are not fully grown they should not be used to measure primary projection.

The outer 10th primary is shorter than the 9th, a diagnostic feature of Pacific Golden Plover, American Golden Plover always have a longer 10th primary than the 9th.

The unfeathered area of the tibia on fulva is longer than dominica with dominica showing extensive feathering and probably fulva has a longer tibia than dominica and therefore appears to have longer legs.

The call has been heard and is considered by one observer to sound like Pacific Golden Plover (Dave Holman per Peter Allard).

There are lots of other minor features that further confirm that the bird on Breydon Water is a Pacific Golden Plover and I cannot actually see any features that would suggest that it is an American Golden Plover in this plumage at this time of the year. I have also seen Pacific Golden Plover identical to the Breydon Pacific Golden Plover in Oman in several March/April visits in the last 10 years.

Acknowledgements

I would like to particularly thank Dave Appleton for allowing me to use three of his photographs of the bird in flight showing the bent outer primary on the left wing, the shorter outer primary on the right wing and the general dark brown upperparts from a distance:-

http://www.gobirding.eu/Diary/Diary.html

and many thanks to Graham Etherington for allowing me to use the closer photograph below demonstrating the shorter outer primary - JanJ has already pointed towards his web site where there are further photographs of the Breydon bird.

Finally thanks to the extensive discussions with the finder Peter Allard.

Andrew Grieve

[appleton.dave]

Some interesting points Andrew - thanks. The fact that it's been heard calling, apparently like a Pacific, is especially interesting.

It will take me more time than I have tonight to digest this fully, but a quick response about the left wing. I have one photo of the wing during preening which I think, despite being of poor quality, proves that the primary that some have suggested is missing is in fact present, but not fully grown.

http://www.gobirding.eu/Images/Waders/Plovers/AmericanGolden/American%20Golden%20Plover,%20Breydon,%2010-Apr-09%20(A21)%20L.JPG

The white shafts are clearly visible in the outer primary, the "missing" primary and the next three in. The placement of the white on the second outermost primary is nearer the base compared to the adjacent feathers which I presume must indicate that the second outermost primary is not fully grown, as opposed to broken at the tip (or missing).

I can accept that the left wing has been damaged at some point. That might explain the droop and it might (?) explain why it's still growing this primary when, I understand, it shouldn't be on either species. Of course if it has experienced some trauma then this could have had a more significant effect on its moult strategy, which could perhaps explain some of the other anomalies?

Is it normal for damage to a primary to make it appear longer? My simple brain makes me think it would only be longer relative to the rest of the wing feathers if it was pulled out slightly, in which case I would expect it to fall out. I could see that the bird might hold its wing back further effecting the length relative to the tail, but I would expect that to be obvious at the shoulder end. But I don't know about this - perhaps it is possible?

Cheers,
Dave

[Jeremy.Gaskell]

Thank you to Andrew Grieve for an illuminating if a trifle adversarial discussion of some of the key i.d. features of the two 'Lesser' Golden Plovers.

Leaving aside the question of the primary projection, which seems so dependent on an appreciation of whether or not the tertials have reached their full length, there are other matters to be put into the balance. I would like to draw attention to one of these that appears not to have attracted much attention and tho' mentioned by various authorities is not often stressed. I refer to the more extensive yellow or buff plumage on Pacific as compared with American. Indeed this is a reflection of the Latin name 'fulva' from which we derive the adjective 'fulvous'.

An examination of photographs of P. fulva taken in the first three months of the year confirms that this form does indeed begin to acquire its 'alternate' plumage quite early on, with black feathering beginning to show through by March. The fact that the Breydon bird is only just beginning to show this tends to demonstrate that the bird is indeed a month behind the moult sequence of its congener as shown in photographs taken in different parts of the globe. Such photographs also show an extensive golden yellow foreneck and upper breast of the birds. Indeed signs of yellow on the underparts of of Pacific Golden Plovers in 'basic' and immature plumages are almost invariably detectable to a greater or lesser extent. This feature is entirely lacking on the Breydon bird, something which, I submit, weighs heavily in the balance in favour of the bird's indentification as American Golden Plover.

Regarding the call the pre-war American writer Forbush, in reference to birds met with on the Atlantic seaboard, hence P.dominica, gives "A harsh whistle, queedle, or quee," suggesting either a disyllabic or monosyllabic call. A Nantucket sportsman quoted by Forbush stated, "When approachng the decoys every bird seems to be whistling, or as I have expressed it, uttering a note like 'coodle, coodle,coodle'." Interestingly enough in view of the behaviour of the Breydon bird he added, "During the middle of the day they are fond of seeking the margins of ponds, where they sit quietly for a long time if undisturbed. When disturbed they are almost certain to return, in a short time, to the same spot from which they have been started, that is if they have been resting or feeding there any length of time."

Forbush informed his readers that the American Golden Plover very nearly met the same fate as the equally confiding Eskimo Curlew

[CAU]

A few points, that may not be too relevant:

1. To me the length of P10 does not seem to be a too useful (or clear) feature.
Wings of AGPs (above: ad August, below: juv September):
http://www2.ups.edu/biology/museum/AGPLwing11439.jpg
http://www2.ups.edu/biology/museum/AGPLwing1.jpg
Wings of PGPs (above: ad April, below: juv September):
http://www2.ups.edu/biology/museum/PGPLwing21817.jpg
http://www2.ups.edu/biology/museum/PGPLwing20373.jpg

2. Here are claimed AGPs that are in a quite advanced stage of moult in April:
http://www.terra.es/personal5/arbmor/arbsi011.htm
(interestingly, the first picture seems to show a primary projection of three tips only on the right wing, even as the longest tertial is very worn, but the PP of the left wing shows apparently four tips)
http://www.surfbirds.com/cgi-bin/gallery/search2.cgi?species=american%20golden%20plover&photographer=&location=&county=&start=141
(scroll down to the Camargue bird)

3. The discussion of the Spanish bird in the link above reveals that some PGPs from NE Siberia may have as long wings as AGPs according to "Russian papers" (whatever the length of wings means in terms of number of primary tips exposed behind the tertials or wing projection behind the tail)
http://www.terra.es/personal5/arbmor/arbsi012.htm

4. The old feathers of the Breydon bird look fresh enough to have been moulted during the winter, as do the primaries (but this may be difficult to judge). Compare to the very worn old tertials of the Spanish bird (the primaries of the Spanish bird look fresh, which would point towards AGP, if it's a 2cy bird).

[Brian S]

Andrew

By conicidence, I went to see the bird again today, but without having read your lengthy response.

I have carefully read your comments and feel that a lot of what you write is very interesting but (IMO) to some extent speculative, e.g. that the tertials are not fully grown, that the length of the outer primary may be diagnostic of one form or another, that the golden colour to the upperparts should not be found on fulva, etc.. I also find several points misleading and confusing, e.g. the call, which as described doesn't sound like either form and surely not fulva. I believe that care has to be taken not to fall into the trap of concentrating so much on minutiae that what the bird really looks like is ignored...

For example, let's take the primary projection, as anybody seeing the bird will not fail to be impressed with this aspect of the structure. This bird has a very attenuated rear end, produced by the primaries extending a long way back beyond the tips of the tertials and the tail tip. As I pointed out the left wing is longer than the right, but certainly not by the 40% you describe - it is slight, c. 2-3mm. This 'pulled out' rear end is a fundamentally important aspect of the bird's structure, and in my experience would identify this bird as dominica- I do not believe that the tertials are still growing and so this will not change much. However, leaving the tertials aside, to me fulva never really seems to be this long-winged. I could go on but won't. Below are two more side on, profile views from today - again apologies for the poor videograbs.

Brian S

[LeeEvans]

After reading Andrew's very detailed and authoritative note last night, I decided to make the effort and travel to see this very interesting bird. Fortunately it was still present in its favourite area of mud and saltings and was showing extremely well. Several local birders including Tony Stride and Keith were present as well as some visiting Lowestoft birders and Brian Small.

I must say that after spending an hour or more watching it, I am totally convinced that it is an AMERICAN GOLDEN PLOVER, most likely in first-summer plumage. Yes, I agree it is particularly golden-spangled on the upperparts, but that is fairly usual with first-summer individuals.

It has a typical fairly short dark grey bill of even width and not the longer and deep-based bill typical of fulva. It is a large bird, has an obvious dark crown and lacks any of the yellow/golden-buff wash I would expect of a fulva in the broad supercilium, in the face and on the underparts. The underparts are typically off-white based with just a few blackish blotches starting to come through on the breast. It has very long tibia (admittedly a pro-fulva feature) and strikingly long primaries, well outside the length of fulva in my opinion, regardless of the fact that several of the tertials are still growing. Another point I would like to make is that the primary feathers seem to be fresh and replaced; first-summer fulvas retain their juvenile primaries and so at this time of year would be very worn and bleached. American Golden Plovers do not retain their juvenile primaries, so a bird with fresh primaries at this time of year is perhaps nore suggestive of an American.

Unfortunately, it did not call whilst I was present, but I am led to believe it gives a disyllabic note somewhat resembling a Spotted Redshank. Well for me that is exactly the call a percentage of vagrant dominicas make, certainly those that Ray Turley and I have found on St Mary's Airfield and Golf Course over the years. In fact, the calls of both fulva and dominica can be remarkably similar but the Spotted Redshank type contact note I agree is most often associated with the Pacific Golden Plover, certainly in the literature and on CD's including the latest Sound Approach one.

In flight, the toes just extended beyond the tip of the tail and the dusky axillaries were very obvious.

This is a most educational bird and I am particularly grateful to both Andrew Grieve and Brian Small for drawing attention to it and soliciting wider interest and discussion as to its identity

Knowing that Chris Heard had just returned from Texas, I phoned him just now. He had fortunately seen several American Golden Plovers during his visit last week and most importantly had the flight calls still fresh in his head. He confirmed my earlier statement - that the calls were basically disyllabic and reminiscent of the Spotted Redshanks distinctive ''chu-wit'' call.

Best wishes

Lee Evans

[JanJ]

I was impressed but not convinced by Andrews suggestions.
Just goes to show that identification of certain AGP & PGP in, perhaps especially, non-breeding plumages can certainly be more complicated than some people might think, thereby not focusing on anyone in particular here. Variation according to bill-size, primary projection beyond tertials and tail, colour and lenght of leg & tibia is to be considered when dealing with seemingly odd individuals. Looking at the bill size and attenuated rear - AGP comes to mind.
I know some skilled birders that looks much more on structurally differences.

The video:

http://www.youtube.com/watch?v=yjHhk769XNs

Some of Martin's Pluvialis might bring something up?

http://www.martinreid.com/Main%20website/obidind.html

...and lots of Pluvialis discussions here, just search the archives

http://listserv.arizona.edu/archives/birdwg01.html

JanJ

[Brian S]

In addition to JanJ's, try these 1-summer PGPs - note length of tertials and p projection.

http://www.hkbws.org.hk/BBS/viewthread.php?tid=7993&extra=page%3D1

Brian S

[Jono Leadley]

Brian,
As one of the "chattering classes" I whole-heartedly agree with you; I am yet to be convinced this is fulva.
Best wishes,
Jono

[Sandgrouse]

A few points, that may not be too relevant:

2. Here are claimed AGPs that are in a quite advanced stage of moult in April:
http://www.terra.es/personal5/arbmor/arbsi011.htm
(interestingly, the first picture seems to show a primary projection of three tips only on the right wing, even as the longest tertial is very worn, but the PP of the left wing shows apparently four tips)
http://www.surfbirds.com/cgi-bin/gallery/search2.cgi?species=american%20golden%20plover&photographer=&location=&county=&start=141
(scroll down to the Camargue bird)

4. The old feathers of the Breydon bird look fresh enough to have been moulted during the winter, as do the primaries (but this may be difficult to judge). Compare to the very worn old tertials of the Spanish bird (the primaries of the Spanish bird look fresh, which would point towards AGP, if it's a 2cy bird).

Hi CAU,

I was going to use the Spanish bird to demonstrate the lateness of the moult in dominica as it still had a lot of older, worn feathers and some old unmoulted tertials (if it was going to moult them). There is some indication in the literature that fulva moult all their tertials whilst dominica do not (BWP) but I suspect this needs further work.

Regarding primary extension I agree with you that you can find both fulva and dominica that do not conform to the expected 3 or 4 primary rule.

I am a little bit surprised that people are comparing the critical plumage features of the Breydon bird with fresh plumaged 1st calendar year birds when comparing mantle and back feather detail and primary projection/extension etc., and even general stance and shape. I have yet to find an image of a second or third calendar year AGP with the so-called bright plumaged mantle and back with golden yellow fringes in March, April or May and not in full summer plumage. Even in full summer plumage (presumably mainly adults) in the early part of the spring, the mantle and back fringes differ between the two species. If you can find some photographs on the web showing bright mantled 2nd/3rd calendar year dominica with golden yellow fringes in April, I would be interested in seeing them. The closest is the Carmargue bird above but the bird is a bit distant to be sure of critical features and it apppears to me to show the more rufous fringes associated with dominica.

Andrew

[forktail]

Hi folks

Lee states that "it is particularly golden-spangled on the upperparts, but that is fairly usual with first-summer individuals."

Andrew states that "I have yet to find an image of a second or third calendar year AGP with the so-called bright plumaged mantle and back in March, April or May and not in full summer plumage."

After lengthy discussions with a couple of birder friends, I'd decided to leave this as an "unidentified" plover as I wasn't happy with a few things (the brightly-coloured mantle) despite the tertial-tail-prims position, dark-capped and attenuated appearance apparently confirming domininca. If anyone can find pics of a first-summer dominica showing such a brightly coloured mantle/back it would surely go some way to resolve matters... so is it fairly usual or unheard of?

Lee's point about dominca not showing retained primaries at this time of year whilst fulva does is also interesting. Is this generally true?

And could someone offer some help as to when the 3-4 primary rule can be used without moult complicating matters?

atb
F.

[Jrhough1]

I read with intrigue, the various comments on the Breydon Lesser Goldie and admit at first glance that the upperparts looked rather yellow, suggestive of Pacific, contrary to the id. of the bird for American Golden. I wasn't going to indulge, but like a moth to a flame, and like everyone else that feels the need to put a label on something and pigeon-hole it, here's my two cents.

On plumage, even though I feel that I have reasonable experience of both species, this is a very difficult individual, as are most first-year "LGP" and I find myself swaying backwards and forwards between both species, but not really seeing the bird in the field is rather a handicap.

I've looked a little more closely at the images and one reason I think the bird is probably an American Golden Plover is that the primaries are rather fresh. In a brief, personal email to LGRE, I had mentioned that assuming this is a first-year bird, Pacific Golden Plovers, unlike American Golden Plovers of the same age, retain their juvenile primaries and do not moult them completely on the wintering grounds, as do American Golden Plovers. Thus, a PAGP at this time of year, if correctly aged as a first-year (second -cal yr) should show rather bleached and worn primaries.
With so much variation in plumage, especially of little known first-years, this may be the feature that is unbiased if indeed, the primary moult timing is reliable.

Also, adult Pacific Golden Plovers moult into breeding plumage earlier than AGP, and so any "breeding" bird in early April is more likely to be a PAGP than an AGP. All the AGP seen in early April in Texas were still in non-breeding plumage with really no obvious amounts of breeding plumage feathers. However, a sick bird, one that has not enough energy to renew it's feathers may be lagging behind. The Breydon bird, at this time of year, i would expect to be farther advanced into summer plumage if it were a PAGP - if indeed the moult schedule of first-years follows the same advanced pattern as the adults when compared to AGP.

Other potentially pro-Pacific Golden Plover points may be the fact that they show a rather broader, dark neck stripe, caused by the supercilium drooping slightly and not reaching as far back onto the nape (M. O'brien, R.Crossley pers comm). It's hard to say from the plumage of the Breydon bird, and the angle of the photos what the exact pattern is.

The wing point does look rather long, but again, I find this a little tough from still images, and coupled with the fact that the tertials are still growing, result in a large amount of exposed primaries, maybe contributing to a long-winged look?

The rather slim bill and dark crown are perhaps more AGP-like, but the overall shape, with a rather pot-bellied look is arguably more Pacific-like.

Since some features are more suggestive to some observers of one species or the other, I do not think overall there are really any diagnostic plumage features on the Breydon bird that really make me plump for either species - leg-length and bill length on their own, on lone birds is basically limited as an id. aid. Calls can be very similar in both species, especially if you've not hear either in a long time.
American Golden Plovers are varibale in their calls, autumn birds here near the house that I see frequently utter a drawn-out "chu-weeee", but equally the flight call I hear as well, is a rather tri-syllabic "kuh-i-lee".

My opinion, is that based solely on moult schedule of the primaries, if it's a solid criterion, is that it's an American Golden Plover.

[CAU]

Lee's point about dominca not showing retaining primaries at this time of year whilst fulva does is also interesting. Is this generally true?


Here's the paper that says so:
http://elibrary.unm.edu/sora/wb/v35n02/p0120-p0124.pdf

Scroll to the very bottom of this page to see what a first-winter Pacific Golden Plover may look like in March (moulting to first-summer plumage):
http://shorebirds.exblog.jp/i61/
The heavy wear of the wing coverts is clearly visible, the primaries look less worn, but they are still brown rather than black.

[jamesg]

A quick point about the moult timing arguments - whichever form this bird is (and I'm in the American camp), it has almost certainly spent the winter a very long way from its 'natural' wintering grounds. Moult timing is likely to be controlled (at least partially) by the bird's circadian rythmns, and hence a vagrant wintering at the "wrong" latitude cannot be expected to follow the normal moult schedule precisely. Differences in moult timing may be consistent at the population scale, but we should be cautious about considering them as 'diagnostic' of vagrant birds.

Of course, this doesn't mean that moult isn't useful in this case. Even if the bird's timing might be a bit 'off', we would still expect it to follow the same moult pattern overall. So any wholesale differences in the feather tracts replaced or retained in the first half of 2cal year might be useful. I think primary moult might fall into this category?

[LeeEvans]

If the bird was an adult then on moult alone (in my opinion) this would make it an AMERICAN GOLDEN PLOVER. Several North American correspondents have sent me recent photographs taken of wintering Pacific Golden Plovers and these, as expected, are virtually moulted into full summer plumage (particularly two in California). As I stated earlier, adult AGP's attain full plumage much, much later in the year, and as many of you know, retain such good looks well into autumn, often into October.

Likewise, first-years of both species follow a similar pattern. I do not know anyway (other than perhaps handling or of a known individual) of determining either species in 2nd or 3rd year. Both are species which attain full plumage after one year.

Julian Hough sums it up perfectly from a North American perspective but I do agree that the amount of gold in the upperparts is very unusual for an AGP.

[Brian S]

After lengthy discussions with a couple of birder friends, I'd decided to leave this as an "unidentified" plover as I wasn't happy with a few things (the brightly-coloured mantle) despite the tertial-tail-prims position, dark-capped and attenuated appearance apparently confirming domininca. If anyone can find pics of a first-summer dominica showing such a brightly coloured mantle/back it would surely go some way to resolve matters... so is it fairly usual or unheard of?


I suspect that the brightness of mantle colour is variable in both AGP and PGP, in various plumages even juvenile. A very quick search finds these four juveniles, from bright and golden to almost white notches.

http://www.pbase.com/image/102710937 (http://www.pbase.com/image/102710937)

http://www.pbase.com/image/91078175 (http://www.pbase.com/image/91078175)

http://www.pbase.com/image/101681938

http://www.pbase.com/image/90985221 (http://www.pbase.com/image/90985221)


Brian S

[Jrhough1]

I was curious to know what features people are using to age this bird, since that was one point I omitted from my previous post?

J

[jamesg]

Hi Julian,
As I understand it, the ageing is rather dependent on which species you think it is...!

If you believe it's a Pacific, it has to be an adult as it has fresh primaries. As such, it's rather surprising how little summer plumage it has acquired...

If you believe it's an American, it could be 2cal or older, as all ages have a complete winter moult. The fact that it has moulted so many golden upperpart feathers, as Andrew pointed out, suggests it's a fair way into its "pre-breeding" moult. Therefore, the fact that it hasn't acquired any black feathering below suggests to me that it's likely to be a 2cal. I can't really imagine it miraculously turning into a full adult summer over the next few weeks - more likely it will remain dowdy with a few hints of summer plumage, as is typical of 2cal birds. Could easily be proved wrong though!

Either way, as far as I can see, the fresh primaries combined with a limited extent of "adult" summer plumage suggest that it is AGP (along with the extremely telling structural features).
J

[Sandgrouse]

I read with intrigue, the various comments on the Breydon Lesser Goldie and admit at first glance that the upperparts looked rather yellow, suggestive of Pacific, contrary to the id. of the bird for American Golden. I wasn't going to indulge, but like a moth to a flame, and like everyone else that feels the need to put a label on something and pigeon-hole it, here's my two cents.

On plumage, even though I feel that I have reasonable experience of both species, this is a very difficult individual, as are most first-year "LGP" and I find myself swaying backwards and forwards between both species, but not really seeing the bird in the field is rather a handicap.

I've looked a little more closely at the images and one reason I think the bird is probably an American Golden Plover is that the primaries are rather fresh. In a brief, personal email to LGRE, I had mentioned that assuming this is a first-year bird, Pacific Golden Plovers, unlike American Golden Plovers of the same age, retain their juvenile primaries and do not moult them completely on the wintering grounds, as do American Golden Plovers. Thus, a PAGP at this time of year, if correctly aged as a first-year (second -cal yr) should show rather bleached and worn primaries.
With so much variation in plumage, especially of little known first-years, this may be the feature that is unbiased if indeed, the primary moult timing is reliable.

My opinion, is that based solely on moult schedule of the primaries, if it's a solid criterion, is that it's an American Golden Plover.

Hi Julian,

Some excellent comments as always. However (there is always a however!) I find it very difficult to tell how much wear there is to the primaries on the Breydon bird and photographs are inconclusive. These outer primaries have to keep going for at least another 6 to 7 months by which time they will then obviously look very worn but is that the case at this time of the year even if they are the original juvenile primaries? To illustrate this, the excellent Japanese site that CAU has referred to already, shows a second calendar year PGP in March (not in April unfortunately) - bird D and also shows the same bird? in November, and it is difficult to tell if the primaries are obviously worn between the photographs even though these must be the original juvenile primaries - and I am fully conversant with the primary moult strategy of first calendar year dominica moulting in their first winter.

Another second calendar PGP is shown on another page of the Japanese site and again feather wear of the primaries between the earlier photograph and February is very difficult to assess.

http://shorebirds.exblog.jp/pg/blog.asp?eid=c0071489&iid=61&acv=&dif=&opt=2&srl=5832295&dte=2007%2D04%2D03+20%3A44%3A00%2E000

Note that the 2nd calendar bird from Japan in mid February still has two old tertials.

I do not think the Breydon bird is an adult but rather a 2nd or perhaps 3rd calendar year bird as some PGP may retain non-breeding (or basic) plumage through their second calendar summer, and perhaps into the start of their third calendar year as well, which would add to the difficulty of judging the species of the bird on primary wear.

[JanJ]

I suppose you have seen Martin Reids contribution to the Norfolk dominica (:wink:) plover on ID-FRONTIERS, put there by Lee, which I find interesting. It highlights - again - the difficulties to identify these two, especially in certain ages and plumages, a true challenge for those who want one. Perhaps a little more of a non prestigious attitude could be applied, but then again, where would the world be without, at least some of it?

http://www.virtualbirder.com/bmail/idfrontiers/latest.html#9

JanJ

[CAU]

One thing that I've been wondering about is the usefulness of comparing the length of the legs with the length of the tail. Martin Reid wrote that it's very unusual that the legs project behind the tail on AGPs in flight. A few days ago I searched for flight images of AGPs on the net, and found these (these are all images that I found):
http://www.pbase.com/image/50669646
http://www.pbase.com/stevemetz/image/104529826
http://www.pbase.com/stevemetz/image/104527770
http://www.tatzpit.com/data/Images/%D7%AA%D7%A6%D7%A4%D7%99%D7%AA%20%D7%97%D7%95%D7%A 4%D7%96%D7%99%20%D7%90%D7%9E%D7%A8%D7%99%D7%A7%D7% 90%D7%99%20909%20copy.jpg
http://www.tarsiger.com/images/linto/PludomKI6W0759.jpg
http://www.flickr.com/photos/sa_young/1383222828/
http://www.flickr.com/photos/nmcrotalus/3399086238/
http://www.flickr.com/photos/9476593@N04/3384927236/
http://www.pbase.com/image/110599370
http://www.flickr.com/photos/9476593@N04/3384113445/
http://www.flickr.com/photos/dotbleu1/2816052710/in/photostream/
http://www.flickr.com/photos/carlosbettencourt/3028550554/
http://www.pbase.com/image/86629876
It is difficult to assess whether the feet are perfectly aligned with the tail or not, and what kinds of effects the photographic angle can cause, but at least based on this sample it would seem to me that the feet may project quite often behind the tail on AGPs.

Martin Reid's idea that the bird is actually still moulting the primaries sounds good to me, I didn't know that the primary moult can extend to April (or even May). Martin wrote that P10 may be longer on the left wing because it's an old feather, whereas P10 on the right wing is still growing. However, if P10 on the left wing is an old feather (it looks like that in Brian's pictures, now that I look at them again, being browner and pointier), it is probably in the process of falling off, and may extend a bit further because of that (at least D. Forsman has warned that primaries that are in the process of falling off look longer on raptors and may affect the wing formula). Anyway, the moult itself is a strong feature pointing towards AGP (at least compared with a 2cy PGP), like mentioned so many times earlier.

[CAU]

Another second calendar PGP is shown on another page of the Japanese site and again feather wear of the primaries between the earlier photograph and February is very difficult to assess.

http://shorebirds.exblog.jp/pg/blog.asp?eid=c0071489&iid=61&acv=&dif=&opt=2&srl=5832295&dte=2007%2D04%2D03+20%3A44%3A00%2E000

Note that the 2nd calendar bird from Japan in mid February still has two old tertials.


Hi Andrew!

Although the wear of the primaries is difficult to assess on that bird, the wear of the old tertials and greater and median coverts is not. Often when a bird moults the remiges, the wing coverts are also moulted. A partial moult, which doesn't include the remiges, usually doesn't include all of the wing coverts either (though often some and sometimes all, depending on the species). A first-summer PGP can be aged because of retained worn juvenal wing coverts, a feature which is probably usually easier to assess than the wear of the primaries. The Breydon bird, however, seems to lack any such heavily worn coverts, which does not fit a typically moulting 2cy PGP.

[Sandgrouse]

Martin Reid's idea that the bird is actually still moulting the primaries sounds good to me, I didn't know that the primary moult can extend to April (or even May). Martin wrote that P10 may be longer on the left wing because it's an old feather, whereas P10 on the right wing is still growing. However, if P10 on the left wing is an old feather (it looks like that in Brian's pictures, now that I look at them again, being browner and pointier), it is probably in the process of falling off, and may extend a bit further because of that (at least D. Forsman has warned that primaries that are in the process of falling off look longer on raptors and may affect the wing formula). Anyway, the moult itself is a strong feature pointing towards AGP (at least compared with a 2cy PGP), like mentioned so many times earlier.

Interesting comments and I will add another here. The bird occasionally showed some agitation with the left wing. Not only did the left wing droop down more than the right wing when at rest, which some photographs show, it occasionaly fidgeted with the wing by flicking it and trying to shuffle it back to the resting position along the body, actions I associate with slight discomforture.

[Sandgrouse]

I suspect that the brightness of mantle colour is variable in both AGP and PGP, in various plumages even juvenile. A very quick search finds these four juveniles, from bright and golden to almost white notches.

http://www.pbase.com/image/102710937 (http://www.pbase.com/image/102710937)

http://www.pbase.com/image/91078175 (http://www.pbase.com/image/91078175)

http://www.pbase.com/image/101681938

http://www.pbase.com/image/90985221 (http://www.pbase.com/image/90985221)


Brian S

There is no argument that juvenile AGP occasionally show a more golden mantle but I have take issue with you in assuming that later plumages of AGP show this, particularly in April and when dealing with sub adult birds not in full breeding plumage.

[Jrhough1]

Sandgrouse,

You make some sensible and reasonable comments with regards to moult and ageing, and I agree that it's difficult to try and assign a moult pattern to a bird that may not be exactly easy to age, thus any id. based on that may be somewhat fallible.

I really haven't looked at moult and ageing of non-juvenile plovers, so I'm not sure exactly what age the Breydon birds is.

I also agree that comparing this bird with one in juvenile plumage has limited use when talking in terms of plumage detail.

An interesting bird and definitely one to get the grey matter flowing.

J

[Brian S]

Andrew

You take issue with my assumptions, yet in your initial posts you also make assumptions. What I am trying to point out is that I cannot disregard all that stands in front of me (re structure, moult and all other plumage elements) just because it has more golden fringes on the mantle and scaps.

BTW, I have sent all of my images to someone in Hong Kong for his comments, looking at from the other way, so to speak (ie does it look like a fulva), and they have come back stating,

'I would have said dominica. The primary projection is obviously long, and way too long for most fulva (although if you look on OBI you can find one or two birds which approach this bird). However the plumage is not right for fulva; in particular the very dark (and plain) crown, strong super and dark ear coverts are very striking and I cannot ever recall having seen this combination on a similarly aged fulva. It is the head pattern (especially the dark crown) which actually stands out most to me. I also think the gold fringes on the moulted feathers are narrow for fulva.'

Finally, you also state that the tertials were still growing, yet when I compare the first images on BF with my own seven days later thetertials are identical in length.

Brian S

[Brian S]

Julian

Are these AGPs first-summers?

http://www.pbase.com/dickbaxter/image/99276903 (http://www.pbase.com/dickbaxter/image/99276903)

http://www.pbase.com/image/107284804 (http://www.pbase.com/image/107284804)

http://www.pbase.com/image/77337085

Brian S

[JanJ]

A good discussion on the identification and ageing of the "Golden Plover in Colorado" -which I suddenly remember can be viewed here. It starts on 07/05/08, with some images of it to. One (important link, which I have seen some time ago doesn´t work anymore). The contributions of P. Pyle and K. karlson are most informative.

http://listserv.arizona.edu/cgi-bin/wa?S2=BIRDWG01&m=9803&I=-3&q=golden+plover

JanJ

[CAU]

Therefore, the fact that it hasn't acquired any black feathering below suggests to me that it's likely to be a 2cal. I can't really imagine it miraculously turning into a full adult summer over the next few weeks - more likely it will remain dowdy with a few hints of summer plumage, as is typical of 2cal birds. Could easily be proved wrong though!


Probably most here already know that an interesting Lesser Golden Plover wintered in Australia this winter. Most people (seem to) think that it's an American Golden Plover, and I can see their points (both regarding the structure and plumage colour, although the wings could perhaps be even a bit longer). Especially interesting about the bird is that there exists a long series of photos of the bird from January to late March, which allows you to follow how the plumage of the bird has developed:
http://www.flickr.com/photos/tunpin/
http://www.pbase.com/davidstowe/american_golden_plover

Although this might be slightly off-topic as this thread is about the Breydon bird, I hope that the Australian bird may provide some informative details regarding the moult and ageing (at least for those that are less experienced with these).

1. The first photographs from mid-January revealed extremely worn outermost primaries:
http://www.flickr.com/photos/tunpin/3276157170/
My first thoughts were that such extremely worn primaries in mid-winter would perhaps point towards a 3cy PGP with still juvenal outer primaries. However, one year old primaries of adult (older than 2cy) AGPs may presumably look quite worn, too.

Anyway, I would guess is that the wear is too strong for a first-winter bird. For example, if some PGPs may perform three migrations with the same juvenal primaries, it would be quite strange if juvenal primaries would look that worn already during the first winter (at least provided that the juvenal primaries of AGPs don't wear faster than those of PGPs).

In mid-January, there were two different generations of coverts and scapulars visible (some coverts are perhaps missing due to moult):
http://www.flickr.com/photos/tunpin/3276157342/

2. In mid-winter the bird showed a few very worn outer median coverts, and at least most of the other coverts looked newer (on the right side):
http://www.flickr.com/photos/tunpin/3274480574/
The primaries are still growing.

3. It had acquired a fresh greater covert by mid-March:
http://www.flickr.com/photos/tunpin/3343246843/

4. It’s appearance did not change much by late March, at least as far as I can see:
http://www.flickr.com/photos/tunpin/3391529289/

If my assumption that the bird is older than 2cy is correct (the assumption was based on the wear of the old primaries in January), this should show that even an adult bird may be mostly in basic plumage in late March.

[Jrhough1]

Brian,

Howdy! Hope you're well?

I'm at work so took a quick look and not sure about pic1 - could be a first-summer, I'll have to do some research -it's an age I'm not familiar with and would have to confer with other, more knowledgeable people. Other than adults in late spring and fresh juveniles, I feel somewhat out of water these days with these birds!

Pic 2 (23 Jul bird) labelled as an Amercian Golden, actually looks like a Pacific Golden Plover to my eyes !!
when I look at the images and the third pic, I couldn't open.

The PAGP-like bird has a long bill, rather compact appearnace, short-wings and seems to show boldly streaked crown, remnant barring along the flanks and worn primaries and tertials...comments?

Do you know wher that shot was taken?

Here we go again..

J

[CAU]

Pic 2 (23 Jul bird) labelled as an Amercian Golden, actually looks like a Pacific Golden Plover to my eyes !!


Those were my thoughts also. Here's a summer PGP for comparison:
http://www.tarsiger.com/gallery/index.php?pic_id=muu1112480634&lang=eng
I presume both are first-summer birds because of the heavy wear of the wings. At least the bird in Brian's link seems to show three different generations of feathers, i.e. heavily worn brown ones, moderately worn ones with white markings and rather fresh looking ones with yellow markings.

Brian's third link does work for me. The bird seems to show also three different generations of feathers (provided that those with yellow markings belong to a different generation than those with white), but so did the Australian (presumably older than 2cy) plover in late March.

[Brian S]

Hi Julian

All is well, thanks, tired it seems, as you are right about the 2nd image being PaGP. No idea where taken, all info from the site.

Brian S

[Graham Etherington]

Hi Julian

All is well, thanks, tired it seems, as you are right about the 2nd image being PaGP. No idea where taken, all info from the site.

Brian S

Hi guys,
With regard to the second photo (http://www.pbase.com/image/107284804), I think that all the following photos are of the same bird and were taken at Bottle Beach, WA, USA on 23 July 08.
http://www.pbase.com/mtgoat123/image/107284797
http://www.pbase.com/mtgoat123/image/107284794
http://www.pbase.com/mtgoat123/image/107284792
Cheers,
Graham