(3
images) Herring
Gull C9J47
2cy (argentatus),
July 09-15 2003, Tampere,
Finland (61.31N,
23.43E).
A 2cy argentatus, ringed white
C9J47 as pullus
on June 24 2002 in Vkoski, Finland (61.16N 24.09E). The complete moult is well underway with
most wing-coverts and the inner primaries moulted to second generation.
Primary P7 has been dropped and P8-P10 still juvenile. P1-P5 are fully
grown second generation flight-feathers. Most tail-feathers still present.
Most tertials and the wing-coverts are replaced for second
generation feathers. Tertials #1-2 have been replaced, #3 is growing and
the lower tertials are still juvenile. One inner greater covert is still
juvenile (probably #4), while the central greater coverts are missing. The
new greater coverts grown in descendant order, from the outer-wing
inwards, as is the common sequence. The gap in the median covert row is
almost closed, with two feathers still growing. Most juvenile wing-coverts
can be found in the lesser coverts. The upper lower scapulars have been
replaced recently, probably for third generation feathers, as the
scapulars in the lowest row have been moulted previously. Again, the fresh
scapulars look very second generation like. The fresh scapulars
strongly contrast with the old abraded second generation feathers, not as
much in pattern but in wear and tear.
By July, the warm brown tones of the first moulted
second generation feathers
(inner greater coverts and inner median coverts) are faded to
plain white, leaving a contrasting barred pattern on the wing-coverts. 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 are distinct "washed
out" brown, showing the common vermiculated pattern of 2cy argenteus.
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 tables below, the primary moult
scores of 2cy July argentatus in Finland can be read:
Primary
moult score of 2cy argentatus Herring Gull, at Tampere
landfill, Finland (61.33N,
23.59E) on July 10 2003. |
. |
P4
fg |
P5
fg |
P6
fg |
P7
fg |
?
fg |
n: |
P6-P10 |
- |
- |
- |
- |
- |
- |
P7-P10 |
5 |
4 |
- |
- |
6 |
15 |
P8-P10 |
1 |
54 |
6 |
- |
13 |
74 |
P9-P10 |
- |
11 |
34 |
- |
2 |
47 |
P10
old |
- |
- |
1 |
1 |
- |
2 |
n: |
6 |
69 |
41 |
1 |
21 |
138 |
n
= 138; m old P = 2.7; SD old P = 0.67.
Survey at Tampere, landfill, in resting group at 'the saddle',
about 200 2cy Herring Gulls, probably 100% argentatus.
P6-P10 = P6-P10 are still old and present.
? fg = fully grown not known. Fully grown primary score most
probably P6 or less.
fg = fully grown. In our field surveys, a primary is 'fully
grown' when it exceeds the previous feather in the folded
wing. Actually, such 'fully grown' feathers may have to
grow a little, but under field circumstances, it's very
difficult to find out if the waxy sheath, which is the
standard measurement for fully grown primaries, is still
present. |
Primary
moult score of 2cy argentatus Herring Gull, at Tampere
landfill, Finland (61.33N,
23.59E) on July 13 2003, 15:00 h. |
. |
P4
fg |
P5
fg |
P6
fg |
P7
fg |
?
fg |
n: |
P6-P10 |
- |
- |
- |
- |
1 |
1 |
P7-P10 |
2 |
- |
- |
- |
4 |
6 |
P8-P10 |
- |
26 |
6 |
- |
18 |
50 |
P9-P10 |
- |
20 |
52 |
1 |
5 |
78 |
P10
old |
- |
- |
5 |
3 |
- |
8 |
n: |
2 |
46 |
63 |
4 |
28 |
143 |
n
= 143; m old P = 2.4; SD old P = 0.69.
Survey at Tampere, landfill, in resting group at 'Bio I'. |
|