Mew Gull Larus canus canus; heinei; kamtschatschensis; brachyrhynchus

(last update: March 12, 2012)

Mew Gull DKC 5096091 5cy, 01 December 1996, Malmö, Sweden.

Figure 26: 5096091 (361/91,2) five-year old bird (5CY), with dark alula, 01 December 1996. Originally ringed on 15 December 1993 in Denmark.

In the data set of 12 five-year old birds, five have three mirrors. The majority of the birds have black on six primaries but the range is 5-8. The only bird which shows black on P3 is depicted in fig 25. The black alula is not a safe criterion to age three-year old birds, as it still present in one five-year old bird as well (see image below). All 12 birds have white tails and white tips on P7-P8. A mature bird in which the mirror on P10 merges with the white tip (broken black sub-terminal band on P10) is shown in fig 27. This P10 pattern becomes more common on older birds, usually from about seven-year old plumage, but sometimes seen in younger birds (e.g. the second-year bird in fig 17).

Figure from:
Is it possible to age subadult Mew Gulls Larus canus?
by: Kenneth Bengtsson & Lennarth Blomquist, publication in: Anser 2-42(2003): p 73-92.