See lots more photos of this bird here
A huge amount of discussion took place on the Surfbirds site and elsewhere, when a drake Baikal Teal turned up at Minsmere. Like so many rare wildfowl that turn up, the provenance of such records are nigh on impossible to assess accurately, though for many the chance to see such a good bird was simply enough.
The story started on Sunday 18th November when Will Miles put Paul Green onto an interesting duck, which he identified as a drake Baikal Teal. By the evening a few locals had been lucky enough to scrutinise it closely and to eliminate any hybrid characters, plus to confirm that it was fully-winged. The bird has stayed into December and is now developing the vertical flank line characteristic of the species.
Structurally, it was a little bigger than the Eurasian Teal with which it resided; it had a high crown and quite chunky look. Being a drake, a number of features were crucial to the identification and the elimination of a hybrid: the head pattern; the pattern of the scapulars, flanks, tail, upper-tail and under-tail coverts, the tips of the greater coverts and the secondaries; as well as the leg colour. None of these features fitted anything other than pure Baikal Teal.
The head pattern was classic Baikal Teal, and gradually developed into the bright classic male Baikal head pattern. A dark forehead and high crown (initially slightly obscured by brownish tips) ran down through the eye and, as a thin line (like mascara tears) crossing a buttery yellow cheek patch onto a black throat the yellow in front of the eye ran up to a point across the lores, above the level of the eye (many hybrids tend to show a subtly different shape to this patch). There was a slightly paler spot at the base of the bill. Narrow white supercilia ran back from the eyes to join at the rear forming quite a prominent white mark bordered below by glossy green ear-coverts and hind-neck, which were bordered below by a narrow white line.
On the upperparts, the scapulars had neat, dark brown centres (but not as pointed as adults perhaps), with pale inner and brown outer edges - the rear scapulars were longer and more pointed than the others (notably on the right side) and hinted little of the longer falcations of the full adult. One of the most obvious features on the closed wing, and even more obvious when stretched, was a fairly broad white bar formed by the tips of the secondaries this is not often visible, perhaps hidden by the longer rear scapulars. In flight this was also prominent and contrasted with the black speculum, with glossy green noted on the proximal edge of the inner secondaries. The greater coverts were tipped quite broadly a slightly rufous-buff.
Below, the breast was a rusty pink-brown, neatly spotted and the flanks were distinctly marked with two rows of dark brown scalloped feathers, tipped buff-brown, but with pale internal areas, almost white on some. There was a restricted white belly patch bordered by a line of grey adult-like flank feathers. There was some concern about the lack of the white flank crescent, but by December 1st this feature was beginning to show nicely. The lateral under-tail coverts formed a dark bar either side of the base of the tail and the upper edge of these had a rich cinnamon edge. The upper-tail coverts formed a dark bar across the base of the tail.
The legs were pale creamy grey, almost pink in some lights especially on the feet. The bill was small the size and shape of that of a Eurasian Teal, slightly grey, bit with a dark (cutting) edge and tip.
A lot of the discussion surrounding the bird has not been about the birds identity, but its age: some felt it to be adult on the basis of the scapulars, tertials and tail; others that it was a first-winter on the basis of exactly the same features plus those of the flanks and bill colour. Ageing is clearly very difficult on Baikal Teal in the field; Lewington et al (1991) indicated that there are few if any distinguishing features. However, a detailed examination of key areas may give a clue.
The shape and pattern of the scapulars might possibly indicate a young bird as Ogilvie and Young (1998) portray an eclipse male that shows somewhat adult-like scapulars, but others seen in captivity seem to show feathers much like that of the Minsmere bird; images of young birds show a pattern similar or identical to the Minsmere bird.
In an article by Jackson (1992), photographs of two juvenile males taken on the Aleutians, show similar shaped scapulars and one having flank feathers identical to the Minsmere Baikal. It may well be that flank feathers are not age-determinate as they are in Blue-winged Teal.
Looking at the tertials some felt that the longest tertials were adult types, with broad and bright edges on the outer web; autumn juvenile teal Anas sp. tend to have tertials that show greater wear at the tips accentuating the pointed nature of the feather shape - a first-winter from the Netherlands in 1994 (not accepted as wild) shows tertials with the same rich brown edges, though how is this bird aged? I found it hard to accurately assess the tertials and tail feathers and to use these as ageing criteria, but opinions expressed to me have suggested they indicate it is an adult or a first-winter. I am none the wiser. The bill of adults is also said to be blacker than that apparent on the Minsmere bird.
We can say with absolute surety that it is a male!
Lewington et al. state that after the post-juvenile moult has been completed (late in the first autumn-winter), the plumage seems to be exceptionally difficult to distinguish from the adult male. It may prove impossible to age this bird, but is it really important? If it was an adult male coming out of eclipse, this may in itself be interesting due to the fact that its state of moult was less advanced than the Eurasian Teal around it: comparison with drake Eurasian Teal showed that adults were very much more advanced; whilst first-winter birds were very similar to the Baikal Teal, though perhaps a little more advanced.
Discussions with Peter Kennerley, who has extensive experience of Asian duck including Baikal Teal from Hong Kong and elsewhere in northeast Asia confirms that the majority of Anas sp. in east Asia, including Shoveler and Eurasian Wigeon appear to moult out of eclipse plumage up to four weeks later than their European counterparts. His earliest record of a full-plumage male Baikal Teal in Hong Kong is 8 December although there are records of birds in female-type plumage in early November. Jackson (1991), however, states that Baikal Teal come out of eclipse by the end of October/early November.
I have purposely not speculated on the origin of the Baikal Teal at Minsmere. It is not only an emotive subject, but also a very interesting one, with more to be learned from some of the questions it has raised.
Ogilvie and Young, 1998. Photographic Handbook of the Wildfowl of the World.
Jackson, Birding, August 1992. Field Identification Of Teal In North America (pp. 214 223).
Lewington et al, 1991. A Field Guide to the Rare Birds of Britain and Europe.