1-2: © Ruud Altenburg, 15-01-04. 2cy Yellow-legged Gulls may be very hard to separate from some Baltic Herring Gulls. These too may show a whitish head, overall darker brown juvenile feathers, tertials with narrow pale edges and a michahellis-like tail pattern. The most difficult birds can only be separated by their paler inner hand. The blunt tip to the bill of this 2cy bird is a good pointer for Yellow-legged Gull, as of course are the second generation lesser coverts. In 2 it can be compared to a 2cy Caspian Gull (on the right).
3: © Ruud Altenburg, 11-01-04. Adult at Warszawa Mlociny, sewage outlet.
4: © Ruud Altenburg, 13-01-04. Adult.
5: © Ruud Altenburg, 13-01-04. Red P409 (ring invisible on the photo), 14cy L michahellis. Metal-ringed (Gdansk DA 07182) as pullus on 26-05-91 in Wloclawek, Poland; plastic ring added when trapped on the nest several years later. Although ringed as argentatus, characters noted in the field point to michahellis. Unfortunately, the picture doesn't reveal many of these, but note the complete band on P5. Grzegorz Neubauer had already confirmed this after I had previously seen this bird in Lubna on 02-01-03: "I have "L. argentatus" in my ringing data, but watching this bird in the spring in the colony, I wondered if it is not a michahellis (matched many features with this form!). Before I started my work in the colony last year, all large gulls there were identified as a "L. argentatus", and such data were sending to people (although part of breeding gulls are obviously cachinnans and michahellis!)".