Herring Gull- Zilvermeeuw (argentatus & argenteus)

(last update: 10-1-2007)


Herring Gull plumages:

hg 1cy July
hg 1cy August
hg 1cy September
hg 1cy October
hg 1cy November
hg 1cy December

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

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

hg sub-ad January
hg sub-ad February
hg sub-ad March
hg sub-ad April
hg sub-ad May
hg sub-ad June
hg sub-ad July
hg sub-ad August
hg sub-ad September
hg sub-ad October
hg sub-ad November
hg sub-ad December

hg ad January
hg ad February
hg ad March
hg ad April
hg ad May
hg ad June
hg ad July
hg ad August
hg ad September
hg ad October
hg ad November
hg ad December

Herring Gull DN-12962 2cy (argentatus), August 12 2002, Tampere, Finland (61.31N,23.43E).

A 2cy argentatus, ringed in Poland with a metal ring, Gdansk DN-12962.
The complete moult is almost finished with most wing-coverts and the inner primaries moulted to second generation. The outer primary P10 is still juvenile and P1-P7 are fully grown second generation flight-feathers.
The upper four tertials and most of the wing-coverts are replaced for second generation feathers. The central greater coverts are fully grown and the gaps of the last missing wing-coverts can be found in the upper rows of the lesser coverts. All scapulars have been replaced by at least second generation feathers, including the scapulars in the lowest row.

By August, the fringes of the first moulted wing-coverts (inner greater coverts and inner median coverts) wear away. On average, 2cy argentatus is more contrastingly patterned than same aged 2cy argenteus, especially regarding the pattern on the central greater coverts. However, some argentatus (obviously including this individual) are distinct "washed out" brown. The last moulted coverts are the central greater coverts and outer lesser coverts, replaced by mid-August. From mid-August onwards, 2cy argentatus start the partial autumn moult, starting again to drop the upper tertial and inner greater and median coverts.

In the table below, the primary moult scores of 2cy August argentatus in Finland can be read:

2cy argentatus in August, Tampere landfill, Finland, August 10 2002, 10:00-12:00 h.
  P5 new P6 new P7 new P8 new total old:
P9 old 1 8 8 - 17
P10 old - 15 42 2 59
no old - - 59 4 63
total new: 1 23 109 6 139
old primaries: m = 9.3, SD = 0.69, n = 139.
new primaries: m = 6.9, SD = 0.47, n = 139.