A golden plover:
but which one?
Graham P. Catley, R. A. Hume
and the Rarities Committee
O
n 7th September 1983, R. W. Gibling and Mrs J. Gibling, -visiting the
area from London, watched and photographed a strange wader at Salthouse, Norfolk. It was subsequently submitted to the British Birds Rarities
Committee as a 'Lesser Golden Plover' Pluvialis dominica dominica (now known
as American Golden Plover P. dominica). The record was ultimately rejected as
uncertain, but the discussion that ensued was instructive
J G believed she had found a Dotterel Charadrius morinellus and fetched R W G
to look at it, on the far side of a pool west of the beach road. R W G agreed
that it looked like a juvenile Dotterel, having a prominent supercilium, but
also noted an upright impression, a long neck and long legs. The bird fed
with a rapid run-stop-pick action, interspersed with short, low flights towards
the observers: R W G was taking photographs during this time before the bird
suddenly flew off out of sight towards Kelling. As it flew, it called a 'disyllabic
"tuitt" reminiscent of Spotted Redshank Tringa erythropus, but less sibilant and
either louder or clearer. Used repetitively'. On taking flight—in alarm?—it
uttered a more rapid version.
When R W G saw his photographs, he considered the possibility of other
species. Having realised that Dotterel should have shown a breast band, and
now seeing features that were not noted in the field in the effort to get photographs, R W G and J G concluded that Lesser Golden Plover was the correct
identification.
The photographs submitted were four small colour prints, with images of
the bird up to 3 cm long, all somewhat soft and slightly grainy and all showing the bird with its legs and feet all or partly hidden in vegetation. Each
photograph (e.g. plate 2) shows a neat, apparently small-headed, slender-billed,
cold-coloured golden plover Pluvialis at rest, in a three-quarter side view. This
angle of vision appears to have exaggerated an apparently long extension of
the closed primaries beyond the tail. The head and breast
of the plover are mostly shown against gleaming silvery
water and the forehead, chin and foreneck are all slightly
'lost' against that background, emphasising the apparent
slimness of the head and neck, while the bill is clearly
silhouetted in two, but rather soft, blurred in a third,
and invisible in the smaller fourth image.
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[Brit. Bird, 87: 16-21. January 1994]
A golden plover: but which one?
17
What, then, was the mystery bird? On first circulation (11th February to
13th July 1984) it received four 'Accept' votes, three 'Rejects' and three
Tends' for further expert views.
'Good' points noted were: slim shape, tapered rear, thin neck topped by
prominent head, erect posture, large dark eye contrasting with pale face, and
rather fine bill. The large eye and fairly well-defined supcrcilium were quoted
as good features ruling out European Golden Plover P. apricaria and the call
was well described for a 'Lesser' even when the bird was thought to be a
Dottere 1.
Points against (or easily 'explained') included: slim neck (due to alarm posture); leg length, wing/tail relationship and underwing all missing; bill more
like European's in some voters' view; lack of prominent blackish cap; supercilium too diffuse (looking white, but so docs much of the face in the pictures);
lack of good dark car-covert blob; underpart markings longitudinal rather
than cross-bars; nothing at all on plumage to indicate other than European
Golden. The small bill could be a trick of the photograph (a dark shape
slightly out of focus against a light background) and, while the call and
Dottcrcl-likc look sounded good, there was the observers' lack of experience
with any of the related rarer species to be taken into account, too.
A further complication arose, however, since some 'accepters' thought that
this was not dominka but fulva (Pacific Golden Plover), because the cap did look
prominent enough, the supcrcilium is less prominent on fulva than on dominka,
the car-covert blob was actually quite obvious and the general colour (too
brown for dominka?) was perfect ibrjulva. Also, compared with photographs of
fulva it looked spot-on, too long-necked and thin-necked for European Golden
and lacking a contrasting dark breast band/pale belly effect. Assuming uhat it
was a 'Lesser' at all, then fulva seemed the best bet. This seemed to be the
way the voting would swing.
Independent expert opinion from Tony Pym cast a cloud on this view,
suggesting that it was dominka after all. A second circulation with even longer
comments was inevitable.
The referee's view was not readily accepted by the Committee. It seemed
that die dark areas on the uppcrparts were not so dominant as on a juvenile
(or at least an October juvenile) dominka, which usually shows an almost unmarked dark 'saddle' and whitish spots scattered on a dark background on the
coverts, while fulva is more densely and uniformly peppered with yellowishwhite (light and dark equally balanced). The photographic evidence was
deemed to be somewhat deficient in yellow hues (too much pink, not enough
green), so the apparent lack of yellowness could be illusory. The photographs,
indeed, were questionable as evidence because individual birds can appear
quite different on several photographs according to light and shade, the lens
and film used, processing and printing.
The head pattern, however, still looked to some voters like that of dominka,
with a well-defined dark cap and a pale, well-defined supercilium. The 'small'
bill may have been a photographic trick, but the bill of 'Lessers' is in any case
longer than on Golden, although looking slender and pointed: the apparent
slimness surely favoured 'Lesser? Not all voters agreed.
The long wingtips, long thigh, large eye and slim neck all favoured 'Lesser'
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A golden plover: but which one?
and could not all be illusory it was argued. Flocks of Goldens studied days before never once included a bird so long-necked as tiiis, stated members.
It still did not convince everyone: die neck of a fully alert, lone, newly
arrived European Golden could be stretched long and thin perhaps? And
might it not even call oddly, too?
Some voters, previously convinced, now began to doubt die wisdom of
acceptance on essentially questionable photographic evidence and without at
least a good view of the underwing. Even some photographs oijuha used in
comparison were drawn into question as perhaps themselves of misidentified
birds.
The second circulation ended with five 'Accepts' and five 'Rejects'. It was
to come around again, with other files available for comparison.
By now, of course, the make-up of the Committee had changed. New
blood entered the fray! Well-fed winter flocks of European Goldens, which we
are all used to seeing, are not, it was suggested, the best birds for comparative
purposes: the slim, raised neck might be matched by European Golden after a
long flight, atypical or not. The plumage features were judged to be quite
compatible with Jiiba, not compatible with dominka, but not certainly ruling
out apricaria on the evidence available. Nevertheless, the length of tibia
('thigh'), delicate appearance, dark crown, well-marked supercilia, narrow eyeline running back from the eye, and vertical spot on the lower rear earcoverts, long wings and rather scaled look to the scapulars and wing-coverts
all looked good for 'Lesser' and, given the remarkably good call, it still added
up to an acceptable record for some members of the Committee. The debate
ended widi tiiree acceptances and seven rejections, and the recommendation
that the report be brought forward in a few years' time for review, should
there be more knowledge of the species concerned.
..
2. Golden plover Plwialis, Salthouse, Norfolk, September 1983 (R. W. Gibling)
3 . Adult American Golden Plover Pluvialis dominica completing moult into winter plumage, St Lucia,
November 1985 {Don Smith)
4 . Juvenile/first-winter Pacific Golden Plover Pluvialis Juka, Hong Kong, October 1987 (Ray Tipper)
5 . Juvenile European Golden Plover Pluvialis apricaria moulting to first-winter plumage, Anglesey,
October 1987 {R. J. Chand-ler)
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A golden plover: but which one:
There the matter rested until the autumn of 1992, when the file was unearthed as part of a 'Lesser Golden Plover' review. GPG undertook extensive
study of European Golden Plovers in the field and commented at length on
them and the bird in question. The remainder of this paper is based on his
notes and views.
It was, above all, a good reminder that the real thing is better than any
photograph and that close study of commoner confusion species is essential,
especially as identification papers tend to reproduce few photographs of the
commoner bird amongst many of the rarer options. GPC particularly studied
apricaria in September: the month of the Salthouse claim. One in particular, a
single bird keeping apart from a flock of 525, sounded alarm bells: it was
'odd', but never quite odd enough to suggest fulva, although it did raise the
possibility of confusion. Indeed, while at the identification conference on
Tcxel, Netherlands, the previous year, GPC had heard Californian delegates,
seeing apricaria in flocks for the first time, expressing concern over the close
similarity of non-summcr-plumage European Golden and Pacific Golden and
the very real difficulty of identifying a lone individual in such a plumage.
GPC took the points raised in the Salthouse file one by one:
1. General appearance, long-necked, long-legged, with upright stance and small head on longneck. The apricaria studied could match this. Juveniles tend to look smaller-headed, with a more
'vvaisted' neck than adults in the same (lock. It is, however, not clear why this should be so.
2. length of neck and small head. Alarmed golden plovers of all three species can raise their head
and neck ill alarm, and apricaria can match the bird photographed at Salthouse. likewise, fulva
can look quite dumpy when well fed and resting.
3. I/eg length. The one photograph showing the tibia length well reveals an apparently very long
thigh: apricaria juveniles showed very little unfeathered tibia. This is arguably the best point in
favour oi'fulva for the Salthouse claim.
4. Bill shape/size. The bill of fitlvu can look large and generally has a bulbous tip, but litis is not
always apparent in photographs.
5. Head pattern. The forepart of the head is badly 'burnt out' or over-exposed and looks simplywhite, so there is no possibility of a critical assessment of the forehead, loral or superciliary
patterns. Juvenile apricaria may usually have dense, fine streaks on the forecrown, leaving the area
around the loral spot and the chin as the only really pale areas on the 'face1 (contrasting with
streaked malars/lbrecrown/ear-coverts). This can be shown by some juvenile fulva, although manylook pale-fronted like domadca. T h e photographs in question make judgment impossible on this
point.
6. Hank pattern. It was said that apricaria had streaked, not barred, flanks in one Committee comment, but all three species have an identical flank pattern in fresh juvenile plumage, with pale
creamy-brown feather centres forming vertical bars down the flanks. Most apricaria seem to
moult/wear in this area in winter, but there is remnant barring on some in February: the feature
is irrelevant to the identification argument.
7. Wing length. This cannot be seen clearly. Even if it could, juvenile apricaria has an identical
structure to fuba, with three exposed primaries beyond the tertials and the wingtip falling at or
just beyond the tail tip (the structure is a valuable point in separating fulva from dominica, of
course).
8. liirge dark eye. liqually a feature of apricaria.
9. Contrast between upper breast and lower underparls. This is often obvious on adults, but
juvenile aprimria do. not match this pattern and can be identical to fuba.
10. Call. The most obvious feature in favour of fuba in the Salthouse claim, but calls can, of
course, be atypical, and can be transcribed in ways that may be misinterpreted by others.
A golden plover: but which one?
21
In the end, the Salthouse claim must fail because of a lack of real detail in the
observed features, in particular a lack of any description of the clinching
underwing pattern, but that is no fault of the observers in this case. Even with
such a 'good' call and such long legs, a bird like this falls short of any 100%reliable identification but it could have been as claimed, nonetheless. After
reading a draft of this paper, RWG has commented 'My view after all this
time is that the bird most favoured juha, was probably not dominka, but could
have been a highly atypical aprkaria (even though I've not managed to see
another which seemed as eerily different).'
The present paper is offered as a useful discussion of golden plover identification, but it also serves to remind readers that an entry in the 'records
rejected' list at the end of an annual 'Report on rare birds' is by no means a
statement that a mistake had been made. As we always point out, it can
simply be that, on the evidence presented, die identification was not incontrovertibly established. It also illustrates the amount of work that the Rarities
Committee may be involved in during the assessment of a single report.
Graham P. Catley, 13 West Acridge, Barton-on-Humber, North Lincolnshire DX18
R. A. Hume, 15 Cedar Gardens, Sandy, Bedfordshire SGI9 1ET