Sand-Plover identification, Virginia, USA (1 Viewer)

[Howard King]

but just because one knows how the Bharain/western population of a ssp of LSP/GSP looks like does not make one an expert on the more eastern ssp of the species.

but at least it is of a broader experience, we are not trying to get it down to ssp but to separate a Greater from a Lesser and in that context any experience is just as worthy as any other for comments on the various forums.

Both columbinus and Cassirostris of Greater are regularly recorded here as are for for Lesser mongolus (mongolus and stegmanni) and artifron (artifrons, parmirenisand and schaeferi) -

As to the origins of the Virgina bird I am prepared to wait on the publishing of a decent photograph before I hazard a guess....

 

[phil baber]

Having only seen 1 Greater in Uk. I was struck by how long the bill looked and how "large-headed" compared to this bird. IMO this is a Lesser SP. They have a more "appealing" look IMO.
Compare Howard's 2 comparison photos above. This beautifully demonstrates this.
I always consider GSP to have a "crocodile-head", compared to the more "gentle-plover head" of LSP.
Study the above 2 photos again and you will see this...
Something else that hasn't been mentioned. The length of bill on LSP from base to tip should equate with distance from bill-base to rear of eye.
Use this rule on Howard's comparison photos, and you will see it fits for the right hand bird. But the left-hand bird? The bill is much longer. It is a GSP...as we know.
Now use this rule on these pics of the USA SP...

http://www.flickr.com/photos/jeffamy/

...and you will see the bill-length rule fits perfectly. (Use a ruler if necessary!)

IMO the bird in question is a Lesser SandPlover.

 

[phil baber]

Oh! And the 1st photo shows it in direct comparison with Killdeer to great effect!
Collin's has these 3's total length as thus...

Killdeer 23.5 - 26 cm
GSP 19 - 22 cm
LSP 17 - 19 cm

It does look smaller, rather than closer to Killdeer's size.

But i leave that to your judgement....

 

[JANJ]

Some good links here:

http://www.sunbittern.com/id-sandplovers.html

http://www.californiabirds.org/members/SandPlover.pdf

One of the better where the bill stands out.

http://www.surfbirds.com/cgi-bin/gallery/display.cgi?gallery=gallery10

JanJ

 

[CAU]

http://www.sunbittern.com/id-sandplovers.html

It is important to note that this article is written from an Australian point of view, and the plumage features fit the subspecies mongolus and stegmanni, not the atrifrons group. For example the breast band is described to be more brightly red on Lesser Sandplover than on Greater. However, photographs show that some Lesser Sandplovers of the atrifrons group may have a very orangey breast bands, like this one:
http://orientalbirdimages.org/searc...esult&Bird_ID=1021&Bird_Family_ID=&pagesize=1
Also the Finnish LSP, presumed to belong to the atrifrons group, had a very orangey breast band:
http://www.tarsiger.com/gallery/index.php?sp=find&lang=eng&order=nro,paiva DESC&species=14500

Note also that only the mongolus/stegmanni Lesser Sandplovers (i.e. Mongolian Plovers) have patterned flanks in breeding plumage (contrary to what has been claimed elsewhere), birds of the atrifrons group have white flanks.

 

[JANJ]

It is important to note that this article is written from an Australian point of view, and the plumage features fit the subspecies mongolus and stegmanni, not the atrifrons group. For example the breast band is described to be more brightly red on Lesser Sandplover than on Greater. However, photographs show that some Lesser Sandplovers of the atrifrons group may have a very orangey breast bands, like this one:
http://orientalbirdimages.org/searc...esult&Bird_ID=1021&Bird_Family_ID=&pagesize=1
Also the Finnish LSP, presumed to belong to the atrifrons group, had a very orangey breast band:
http://www.tarsiger.com/gallery/index.php?sp=find&lang=eng&order=nro,paiva DESC&species=14500

Note also that only the mongolus/stegmanni Lesser Sandplovers (i.e. Mongolian Plovers) have patterned flanks in breeding plumage (contrary to what has been claimed elsewhere), birds of the atrifrons group have white flanks.

I know that it is from an Australian point of view CAU, I was in for the bill characters, which I think is more problematic than refered to.

JanJ

 

[AlexC]

Hey all! Long time no post!

So I live in Baltimore and yesterday went on a 3 1/2 hour trek to see this bird - to no avail. It hasn't been seen since Tuesday and has probably moved on. Oh well. At least I can do all this reading about a bird I didn't get to see!

 

[Howard King]

Reading through the PDF file linked to by JanJ I came across the following might be worth a go on a square on photo from Virgina -- I am going to try it first on some off my own photos to see if it works.

http://www.californiabirds.org/members/SandPlover.pdf
JanJ

Hirschfeld et al.: Identification of sand plovers - British Birds 93:162-189, April 2000 page 167

Millington (1988) proposed a formula involving tarsus length (from knee to foot) divided by bill length (from tip to where feathering meets culmen) for identifying the two species from photographs, the ratios being 1.59:1 for Greater and 1.85-1.99:1 for Lesser. Although this formula seems to be fairly accurate, the ratio is difficult to determine, as the angle from which the photograph is taken needs to be considered.

PS had MIXED RESULTS found the bill length to back of eye ratio works much better

 

[JANJ]

A video of the sandplover is on here:

http://www.youtube.com/watch?v=tlBXJyK2tPw

JanJ

 

[lostinjapan]

Here is a link to the photos of the bird I saw on Mishima Island in 2007 which I believe is an 'atifrons' Lesser Sand Plover for comparison

http://www.birdforum.net/showthread.php?t=83736

Sean

 

[KM1]

The Virginia sand plover

Hello all,

I hope I will be excused for posting this reply to the ID Frontiers listserve here, where I can attach a few images. While I am at it, I would draw the attention of ID Frontiers subscribers who are new to Birdforum to check out Howard King's photos of Greater and Lesser Sand Plovers (posting #19, first page of this thread) taken in Bahrain in the past day or two.

I consider the single most important source of difficulty with Greater vs. Lesser Sand Plover, especially when it comes to identifying lone, out-of-range vagrants, to be the widespread perception that Lesser Sand Plover is always "small-billed". Some are (especially when compared with a typical Greater) but compared to Kentish/Snowy Plover, Lesser can, and often does have quite a stout, even moderately heavy bill. This impression may be enhanced if the feathering of the head is pressed close to the skull, or the opposite when the feathers are fluffed out a little, so even in the same individual, apparent bill size may not be constant.

So far as I am aware, most cases of sand plovers where the identification has been disputed have ultimately proven to have involved Lessers mistaken for Greaters, rather than he other way around.

I welcome Erik's explanation of what exactly he is seeing to make him think this bird is a Greater Sand Plover. In spite of my confidence that it is a Lesser, I have to admit that while examining some additional images (and especially the shaky video, here: http://www.youtube.com/watch?v=tlBXJyK2tPw ) I too have felt moments of equivocation and wondered if perhaps I had got it all horribly wrong? This, however, is almost to be expected when looking at a long series of photos of any individual sand plover, especially when most are of poor quality; sooner or later an image will pop up that seems to completely contradict the images either side of it - it is not without good reason that sand plover identification has gained a reputation as one of the more perplexing ID topics we have to deal with in the Palearctic (and now, it seems in the Nearctic). But before we work ourselves up into a sweat, we need to remind ourselves that most of the time - especially when watching the two species together - they are actually rather easy to identify. Indeed, I think most people who see the two species regularly would agree that a typical Greater Sand Plover among Lessers stands out like a sore thumb.

As I mentioned in my previous post, my most recent experience with sand plovers has been in Oman, on the Persian Gulf. I have also studied them in Malaysia, Goa, Thailand and China, and had numerous opportunities to look at the potentially most problematic 'small' race of Greater, (columbinus) during frequent visits to Israel throughout the 80s and 90s. At the risk of committing heresy, in my experience the challenge of telling two species apart is pretty much the same regardless of the subspecies, as the problem is mostly to do with the inherent difficulty in assessing size, shape and proportions, which differ fairly consistently between the two species, but which are not always easy to determine reliably. Attempting this on the basis of a series of fuzzy photos is probably not a good idea...

Looking at the images on which Erik has concentrated, at:

http://birdtrek.smugmug.com/Animals...68310_w5mm7/1/643504800_jcKNB#643505797_4hgA7

I can certainly see some that are less obviously Lesser Sand Plover-like than others (for example images 11, 15 and 18). However none, in my opinion, approaches what I would expect to see in a convincing Greater Sand Plover, especially an example of the larger billed crassirostris/leschenaultii group. All of the images that show the bill in any way clearly against an evenly toned background (for example, 7, 8, 12, 13, 14 ,16 and 17) seem to me to show a bill that is much too short and stubby-tipped for any form of Greater Sand Plover.

I'm afraid I do not concur with overall impression alluded to by Erik of Greater being "better balanced" than Lesser, in fact I have gained an impression of quite the opposite! I think these kinds of impressions can change so much depending on posture, what the bird is doing, temperature etc. that they are of little practical use in resolving the identity of disputed birds. Likewise, subtle differences in the shape of the white wing-bar, tail pattern and degree of toe-projection in flight can confuse the issue as much as clarify it. Unfortunately, leg length and leg colour in these two species often do not correspond with what is 'typical'.

I have posted this response on Birdforum, where I will be able to attach images of some fairly large-billed Lesser Sand Plovers I have seen in Oman. I am also taking the liberty of posting a montage of one of David Wendelken's close-ups and the head of a Lesser Sand Plover I videoed in Oman, and the same shot again with a measurement of the bill-length: bill to eye ratio; I hope you don't object David. In a follow-up posting to Birdforum I will attach some Greater Sand Plover images, for comparison.

I may be mistaken in my belief that the Virginia sand plover is a stout-billed Lesser, but if the evidence can establish this conclusively, I for one will have learned something useful!

Killian Mullarney
Ireland

 

[KM1]

Greater Sand Plovers

Here are a few images of Greater Sand Plover, for comparison:

Killian Mullarney
Ireland

 

[Howard King]

--- but compared to Kentish/Snowy Plover, Lesser can, and often does have quite a stout, even moderately heavy bill. ----

Indeed, I think most people who see the two species regularly would agree that a typical Greater Sand Plover among Lessers stands out like a sore thumb.

Killian Mullarney
Ireland

as an illustration to the many points Killian has made I attach some more images - red hot from the beach this morning....

Pic 1 - left to right -- Kentish just visible - Lesser (as per individual pic 2) - Greater (as per individual pic 3) then Kentish partially hidden and then another Lesser
Pic 2 Lesser; Pic 3 Greater; Pic 4 Lesser with Kentish; Pic 5 Greater with Kentish

 

[JANJ]

I don´t know how many hours I´ve spent looking at the Virginia sand plover, and failed over and over again to be able to come to a conclusion. A mission impossible if not sharp images are provided!

Interesting with sand plover bills, apart from species and racial differences - the different impression from the same individual in different images, like in this swedish Greater:

1. http://www.pbase.com/slisch/image/99611704
2. http://www.pbase.com/slisch/image/99432546
3. http://www.pbase.com/image/99629916

Also the nail lengt - which seems to be a rather consistent feature in sand plovers - is difficult to judge from images in unsharp images, in birds with mud on there bills etc.
No doubt in the swedish bird which part of the bill is the longest. Which leads me to the image of the Virginia sand plover linked in Killian's first set, on which he has measured the bill-length - bill to eye ratio. In that image the lenght of the bill is approx. the same as the lenght from the bill base to behind the eye, which in favour of Lesser. Furthermore, the nail lengt seems to be shorter than the basal part of the bill, also in favour of Lesser.

What about this one then?

http://www.pbase.com/ingotkfr/image/92920248

JanJ

 

[Lappkrabben]

The best shot ( at last when it comes to sharpness and profile) is IMO the latest one in Surfbirds american press-stop gallery and the bird is there called Greater sand plover wich is what i now think it is, based on that photo.

Some difference in bill-shape and dito heaviness when we finally get to see a shot without sun-blurred shape of the bird at good distance. So IMO i was wrong on LSP.

Good writing by JANJ when it comes to talk about having patience on better shots of the birds bill/beak at closer range without "sun-distracting-blurr"

 

[Microtus]

Unfortunately the Virginia sand-plover has not been seen since Tuesday. I hope it comes back so that better photos can be taken.

 

[Howard King]

Lappkrabben so we can assume you now withdraw your previous comments in post No8, No 15 & no20 in which case you owe Erik an apology -

However I had a close look at the photo you mentioned and still am undecided myself ..... one photo out of hundreds which range from the fuzzy to just passable

http://www.surfbirds.com/cgi-bin/gallery/display.cgi?gallery=gallery10
Greater Sand-Plover, Augusta Co., VA, Staunton 8 Sept 2009 © Gerald V. Frost
*** who I hope is not offended by the use of a cut out of his Photo here-- (have emailed him)

I make no comments on my attempts at measurement or on the shape of the bill other than you can read them off the scale at the top and view my bill shape yourselves

 

[Lappkrabben]

Howard, i see we have some differences in when to apologize to a guy in person and when not. I don not feel have stepping on any toes for writing that we are most probably talking different subspecies and that Erik might have studied wrong/different subspecies in Bharain.

It's not that i can't apologize. But there is no reason for doing it to Erik in person, why should i do that? It was just a thought in general and my thoughts was also about that just because one is an authority in ID-skills does not mean that he/her is allways right.

Maybe it's cultural or has something to do with you being Eriks friend. But for me i do not see any reason for a personal excuse to Erik. But that's my thoughts...

I also wrote that i might be wrong in the LSP-camp. So why should i apologise for writing i'm not sure?

So please do not cry out loud. It's a debate about birds!

I thought the words that i now think the bird is a GSP would have been enough for Howard to know that the other posts are "expired". But yes, i withdraw the LSP-thoughts.

And just a thought on how to write in debates, Howard;

who are we in the sentence "so we can assume "? Is it everone who's reding this post? or you personally, or you or someother guy(s)?

I would have appreciate if you wrote "so I can..." because it's your words and not "we".

 

[Martin Garner]

Following a request from Gail Mackiernan last night and subsequent help from Michael Boatwright today in accessing some of the full range of images I think this bird can be identified as a slam-dunk Mongolian Plover. Hopefully these comments are useful and clear enough to follow. From here on I will refer to Greater Sand Plover (generically all forms), Lesser Sand Plover (atrifrons/pamirensis schaeferi) and Mongolian Plover (mongolus/ stegmanni).
My ‘first off’ impressions of this bird are that it does suggest a Mongolian Plover. I know that sounds perhaps a bit over-confident, but that was my gut reaction based on the summer ‘breeding plumage’ still present on head and body (not normally OK for Greater Sand in September) and the bill/ head proportions and the slightly greater ‘rangyness’ compared to Lesser SP; Greater always shows this slightly overlong look to the bill, which seems a product both of the overall bill length and the long nail (though it can be hard to describe) and I just don’t see a Greater SP bill here. All of the UK records for Lesser/Mongolian Sand Plover have begun as ‘Greater Sand Plover’. I also saw a Greater Sand Plover in Cumbria, England in 1988 which was hotly debated at the time and was thought originally to be a Lesser. All kinds of formula/ photos and measurements were used with this latter bird by proponents of its identification both as Greater and Lesser Sand Plover. The mathematical formulas (bill/ eye, head/ bill, bill/ legs etc) seem to have a tendency to be difficult to apply and a reputation for cancelling one another out as the photographs of birds don’t provide empirical data (like biometrics), so while they can be useful sometimes, so I would prefer to focus to other approaches.

To the Virginian bird:


1) Head and Body plumage

It shows clear remnants of worn and moulting summer ‘breeding plumage over the head and especially the underparts. Greater Sand Plover normally undergo at least head and body moult prior to leaving the breeding grounds, so by September should appear to be in ‘winter plumage’ with a few feathers in areas such as wing and tail still to be moulted. Any sand plover still retaining some obvious element of ‘breeding plumage’ to the head and body in August and September will normally prove to be a Lesser or Mongolian Sand Plover. There may be exceptions in regard to moult and vagrants sometimes (though none that I know of), but better to start with the norm.

2) Bill

I agree with other commentators that the bill looks fine for Lesser/Mongolian and I don’t see the slightly ‘clownish’ long nail and bill proportions of Greater. Those who also consider the head and bill to be more Lesser -like have already done a thorough job of attempting to explain why, so I don’t need to attempt to repeat that, suffice to say I agree with Killian Mullarney’s assessment on ID Frontiers and (with photos) on Birdforum.

3) Overall structure

In some shots it looks a long-legged rangy bird. This is subjective but I think Mongolian (versus Lesser) has greater tendency to look rather rangy and sometimes ‘large’, which is maybe why there is a greater tendency for Mongolian to be confused with some Greater S P’s. Mongolian is intermediate in size between Lesser and Greater. In, for example wing length, Mongolian overlaps considerably with Greater, whereas Lesser for the most part does not: Wing length: Greater S.P. = 135 - 155mm, Mongolian S.P. = 128 - 146, Lesser S.P. = 120 - 137.

4) Leg colour and length.

Some myths persist over characters related to the legs of sand plovers, which should be laid to rest. The leg colour in all forms of sand plover is variable. Mongolian Sand Plover frequently show long-looking greenish legs. The only useful comment that might be made in regard to leg colour is that very black legs do not normally seem to be found on Greater Sand Plover. Otherwise any combination of grey though greenish can be found on any sand plover. In regard to extension of the toes beyond the tail, Mongolian can show this, no problem.

5) Tail Pattern.

There are a several shots showing the tail pattern. The darker central tail feathers are found in Mongolian and Greater Sand Plover but not as far as I know in Lesser Sand Plover (pattern is paler and more uniform).

6) Flanks
This seems to have been barely touched on. While I wish the photos resolved better and were less blurry I can see non-white feathers on the flanks on both sides of the bird. They look pale greyish brown and create a slight ‘grubby’ area here. The feathers are on that area of the flanks that butt up to the normal folded wing position and so can be (partly) obscured by the wings. In fact photos with raised wings clearly show there is more dark rear flank feathering hiding under the folded wing. Also because the grey-brown colour on such flank feathers is weak and somewhat translucent –looking, it is not very striking and has to be ‘looked’ for. In these photos it is hard because of the distance and quality of the images. Nevertheless, it is clearly visible on this bird in a number of photos, and I hope others can see it too. (Maybe someone with high quality field notes/ drawings has recorded this). In some shots it just looks like vague browner wash on flanks just below the folded wing but on a few photos (e.g. those by Phil Davis), clear darker-patterned feathers can be seen blowing up against the folded wing (on both flanks of the bird). This is diagnostic for Mongolian being found in 60-70% of birds in winter plumage and so should be expected but not guaranteed. It is not found in Greater or Lesser SP. On Greater and Lesser Sand Plovers the flanks are gleaming white. Occasional ‘fluffed –up’ feathers can look a bit darker as they overlap the brown wing coverts and the colour of the latter ‘shows though’ but that artefact should be discernable as such nonetheless.

Conclusion

So I see a combination of state of moult (pro Lesser/ Mongolian); bill proportions (pro Lesser/Mongolian); tail pattern (pro Mongolian/ Greater); and dark mid/rear flank feathering (diagnostic of Mongolian) giving me confidence that, while the features are subtle and have to be carefully read in the various photos, in their combination, the bird can indeed be identified as a Mongolian Plover.

 

[Howard King]

Martin

Like many I for one appreciate your long and descriptive response to this Forum however I would to seek clarification on your first point that of the moult for Greater Sand Plover. It is a point that I am certain will not change the conclusion. As your arguments on all other points as far as I am concerned outweigh any concerns I have over my query.

Many Greater SP start arriving back here (Bahrain) as early as early July many still retain what I regard as vestiges or remnants of summer plumage - red or tan colour in breast bands in particular. Many Greater stay until November when they move on with only a few wintering by which time of course they have lost any colour associated with summer plumage, ie. have attained full winter plumage.

In post no 19 I attached a recent picture from here of a Greater showing a considerable amount of colour in the chest band, yesterday I photographed another with a slightly less amount of what I regard as retained remnants of summer plumage ie. still shows some colour (see pic attached). I would contend that the amount on the later is equitable with that on the Virgina bird. Maybe I have misinterpreted the definition of remnants of summer plumage I would be interested if you could elaborate further. I have added a second picture of birds from early July (10th) indicating that Greater do move from their breeding ground before undertaking their winter moult