Yellow-legged Gull- Geelpootmeeuw (L. michahellis): 2cy September

(last update: 08 december 2003)


YLG 1cy May
YLG 1cy June
YLG 1cy July
YLG 1cy August
YLG 1cy September
YLG 1cy October
YLG 1cy November
YLG 1cy December

YLG 2cy January
YLG 2cy February
YLG 2cy March
YLG 2cy April
YLG 2cy May
YLG 2cy June
YLG 2cy July
YLG 2cy August
YLG 2cy September
YLG 2cy October
YLG 2cy November
YLG 2cy December

YLG 3cy January
YLG 3cy February
YLG 3cy March
YLG 3cy April
YLG 3cy May
YLG 3cy June
YLG 3cy July
YLG 3cy August
YLG 3cy September
YLG 3cy October
YLG 3cy November
YLG 3cy December

YLG sub-ad Jan.
YLG sub-ad Feb.
YLG sub-ad March
YLG sub-ad April
YLG sub-ad May
YLG sub-ad June
YLG sub-ad July
YLG sub-ad Aug.
YLG sub-ad Sept.
YLG sub-ad Oct.
YLG sub-ad Nov.
YLG sub-ad Dec.

YLG adult January
YLG adult February
YLG adult March
YLG adult April
YLG adult May
YLG adult June
YLG adult July
YLG adult August
YLG adult September
YLG adult October
YLG adult November
YLG adult December

photo 6327: Yellow-legged Gull michahellis 2cy, September 24 2001, IJmuiden, the Netherlands.

Compare the grey tone of the 2cy michahellis with the Lesser Black-backed Gull (graellsii, probably local Dutch intergrade) left. Primary P10 is fully grown, resulting in a primary moult score (PMS) of 50. See Gull Topography for explanation of PMS.
The partial moult in autumn is well underway with the two upper tertials been replaced for at least third generation feather with barred pattern. The exact generation is difficult to proof when dealing with unringed birds which have not been followed over the last two years. As can be seen in several 1cy sections, many michahellis include upper tertials in the post-juvenile (first pre-basic) moult, so the moult in 2cy autumn birds may result in new upper tertials of fourth generation.
The second tertial is still growing. The lower four tertials are still older, either second or third generation feathers. As can be seen in the 1cy sections, not many birds include all tertials in the post-juvenile moult, so the majority of 2cy michahellis have second generation lower tertials (only moulted once during the complete moult last summer).
The inner greater covert are included in the partial moult as well. Most obvious moult is going on in the inner and central median coverts with almost the complete row of new feathers, with fresh grey bases. In the lower lesser coverts, several central feathers are new or missing. The lesser coverts were replaced very recently in the complete moult, which finishes by August, and in this individual, the lessers are excluded from the partial moult in autumn so far.