Heuglin's Gull (L. heuglini / antelius)
(last update:
Heuglini 4cy, February 26 2001, Bahrain: Sittrah parking lot.
In many respects the plumage is the same as the next heuglini. Here, moult seems to be slightly advanced; not so many brown feathers appear. Nevertheless, a division can be drawn between the new innermost median coverts and the abraded central median coverts. Moult progress still continues in the coverts and maybe in the lower scapulars as well. Also, one tertial seem to be shed. Again winter streaking is still present and runs from the lower neck all the way to the side-breast; much further than would be expected in e.g. barabensis. In this sub-adult, the primaries are recently moulted and have distinct but relatively small tips and all primaries are completely grown. The legs are pink.
From this angle it seems a thumbprint is present in front of the eye. Nevertheless it's not particularly a friendly expression this gull has. Left is a Great Black-headed Gull, probably a male.
Exact ageing is difficult as the primary-coverts are not visible. Anyway, fourth winter birds are hard to recognize once the primaries have been replaced in early winter. The grey tone on the upper-parts is darker than 'typical barabensis'. P10 has a black sub-terminal band between white tip and the mirror (apical spot). There are no coverts missing. The white tips of the outer primaries are relatively small compared to adults. The bill is long and parallel shaped lacking an obvious gonydeal angle, as can be seen commonly in cachinnans. There is an obvious broad bill-band. The bill smoothly continues in the sloped forehead, giving the bird a drawn out, elongated expression. The iris is rather pale, unlike the dark iris of most immature cachinnans. Nevertheless, Liebers and Dierschke (Dutch Birding 19:1997) reported >50% of adult cachinnans to show yellowish irises in colonies in SE Ukraine. As is common in winter plumage heuglini there is pronounced neck-collar of dense streaks ands spots concentrated in the hind-neck running down on the sides of the breast. The overall jizz is a long-necked and long-legged bird (although the tibia length is difficult to judge from behind) with a proportionally small head.
