Great Black-backed Gull (Larus marinus)
(last update: July 12, 2015)
Great Black-backed Gull 2cy June
By April, all the primaries are still juvenile or just P1 dropped in most 2cy GBBG checked at Boulogne-sur-Mer (2000-2004). But from May onwards, primary moult progresses rapidly and in May and June, 2cy Great Black-backed Gull can be the most advanced moulting large gull on continental NW Europe (at least NW France - the Netherlands). Moult progress is even further than Yellow-legged Gulls present at Etaples (near Boulogne-sur-Mer), see GBBG 2cy May section.
In June, we have again done some PMS for several taxa in NW Europe. Dat are presented in the tables below:
Tables:
| Primary moult score of 2cy GBBG L. marinus. June 13 2002 - Boulogne/Mer, NW France (50.43N,01.37E). Bert-Jan Luijendijk & Mars Muusse. |
|
| REM 4 (p6 missing) | 10 |
| REM 3 (p7 missing) | 8 |
| REM 2 (p8 missing) | 1 |
| REM 1 (p9 missing) | 0 |
| REM 0 (p10 missing) | 0 |
| n (sample size): | 19 |
| m (average): | 3,5 |
| SD (stand dev): | 0,61 |
| Notes: m (average) = number of remaining old juvenile primaries. |
|
.
| Primary moult score of 2cy YLG L. michahellis. June 2002 / 2003 - Etaples, NW France (50.30N,01.37E). Bert-Jan Luijendijk & Mars Muusse. |
||
| date: | June 13/14 2002 | June 28 2003 |
| REM 6 (p4 missing) | 1 | 0 |
| REM 5 (p5 missing) | 7 | 0 |
| REM 4 (p6 missing) | 25 | 5 |
| REM 3 (p7 missing) | 8 | 58 |
| REM 2 (p8 missing) | 0 | 32 |
| REM 1 (p9 missing) | 0 | 1 |
| REM 0 (p10 missing) | 0 | 0 |
| n (sample size): | 41 | 96 |
| m (average): | 4,0 | 2,7 |
| SD (stand dev): | 0,69 | 0,58 |
| Notes: m (average) = number of remaining old juvenile primaries. Michahellis 2cy unringed birds have been scored on many feather tracts in spring at Etaples, NW France. For tables and charts see YLG 2cy MAY. |
||
.
| Primary moult score of 2cy HG L. argentatus s.l. (most argenteus). June 2002 - NW France & the Netherlands. Bert-Jan Luijendijk & Mars Muusse. |
||
| date: | June 13 2002 | June 21 2002 |
| REM 6 (p4 missing) | 7 | 9 |
| REM 5 (p5 missing) | 23 | 36 |
| REM 4 (p6 missing) | 56 | 43 |
| REM 3 (p7 missing) | 10 | 13 |
| REM 2 (p8 missing) | 0 | 0 |
| n (sample size): | 96 | 101 |
| m (average): | 5,7 | 5,6 |
| SD (stand dev): | 0,75 | 0,83 |
| Notes: m (average) = number of remaining old juvenile primaries. June 13 2002 at Etaples (50.30N,01.37E). June 21 2002 at Scheveningen (52.06N,04.15E). |
||
.
| remaining | 1 |
2 |
3 |
4 |
5 |
6 |
7 |
7 |
8 |
8 |
9 |
10 |
11 |
12 |
| remain/new P | rem |
rem |
rem |
rem |
rem |
rem |
rem |
new |
rem |
new |
new |
new |
new |
|
| n(tot) 213 | jan |
feb |
mrch |
apr |
may |
june |
july |
july |
aug |
aug |
sept |
oct |
nov |
dec |
0 |
. |
. |
. |
. |
. |
. |
1 |
. |
11 |
. |
. |
. |
. |
. |
1 |
. |
. |
. |
. |
. |
. |
. |
. |
8 |
. |
. |
. |
. |
. |
2 |
. |
. |
. |
. |
. |
1 |
3 |
. |
3 |
. |
. |
. |
. |
. |
3 |
. |
. |
. |
. |
. |
8 |
4 |
. |
. |
. |
. |
. |
. |
. |
4 |
. |
. |
. |
. |
2 |
10 |
. |
. |
. |
. |
. |
. |
. |
. |
5 |
. |
. |
. |
. |
4 |
. |
. |
5 |
. |
. |
. |
. |
. |
. |
6 |
. |
. |
. |
1 |
4 |
. |
. |
2 |
. |
6 |
. |
. |
. |
. |
7 |
. |
. |
. |
. |
6 |
. |
. |
. |
. |
13 |
3 |
. |
. |
. |
8 |
. |
. |
. |
. |
2 |
. |
. |
1 |
. |
2 |
4 |
2 |
1 |
. |
9 |
. |
. |
. |
2 |
. |
. |
. |
. |
. |
. |
14 |
5 |
4 |
. |
10 |
31 |
32 |
24 |
5 |
. |
. |
. |
. |
. |
. |
. |
6 |
6 |
7 |
| n= | 31 |
32 |
24 |
8 |
18 |
19 |
8 |
8 |
22 |
21 |
21 |
13 |
11 |
7 |
| average m: | 10,0 |
10,0 |
10,0 |
9,3 |
6,1 |
3,5 |
2,3 |
5,6 |
0,6 |
6,8 |
8,5 |
9,3 |
9,5 |
10,0 |
| 95% CID | 0,00 |
0,00 |
0,00 |
1,16 |
0,61 |
0,29 |
0,87 |
0,89 |
0,32 |
0,27 |
0,34 |
0,45 |
0,46 |
0,00 |
| inverse | 2,04 |
2,04 |
2,07 |
2,36 |
2,11 |
2,10 |
2,36 |
2,36 |
2,08 |
2,09 |
2,09 |
2,18 |
2,23 |
2,45 |
| Variance (s2) | 0,00 |
0,00 |
0,00 |
1,93 |
1,52 |
0,37 |
1,07 |
1,13 |
0,53 |
0,36 |
0,56 |
0,56 |
0,47 |
0,00 |
| SD (s) | 0,00 |
0,00 |
0,00 |
1,39 |
1,23 |
0,61 |
1,04 |
1,06 |
0,73 |
0,60 |
0,75 |
0,75 |
0,69 |
0,00 |
| SE (sx) | 0,00 |
0,00 |
0,00 |
0,49 |
0,29 |
0,14 |
0,37 |
0,38 |
0,15 |
0,13 |
0,16 |
0,21 |
0,21 |
0,00 |
| Percentage | ||||||||||||||
0 |
0 |
0 |
0 |
0 |
0 |
0 |
13 |
0 |
50 |
0 |
0 |
0 |
0 |
0 |
1 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
36 |
0 |
0 |
0 |
0 |
0 |
2 |
0 |
0 |
0 |
0 |
0 |
5 |
38 |
0 |
14 |
0 |
0 |
0 |
0 |
0 |
3 |
0 |
0 |
0 |
0 |
0 |
42 |
50 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
4 |
0 |
0 |
0 |
0 |
11 |
53 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
5 |
0 |
0 |
0 |
0 |
22 |
0 |
0 |
63 |
0 |
0 |
0 |
0 |
0 |
0 |
6 |
0 |
0 |
0 |
13 |
22 |
0 |
0 |
25 |
0 |
29 |
0 |
0 |
0 |
0 |
7 |
0 |
0 |
0 |
0 |
33 |
0 |
0 |
0 |
0 |
62 |
14 |
0 |
0 |
0 |
8 |
0 |
0 |
0 |
0 |
11 |
0 |
0 |
13 |
0 |
10 |
19 |
15 |
9 |
0 |
9 |
0 |
0 |
0 |
25 |
0 |
0 |
0 |
0 |
0 |
0 |
67 |
38 |
36 |
0 |
10 |
100 |
100 |
100 |
63 |
0 |
0 |
0 |
0 |
0 |
0 |
0 |
46 |
55 |
100 |
| % Controll | 100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
100 |
Notes: |
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Great
Black-backed Gull (Larus marinus) JW068 June 01 2011, IJmuiden, the Netherlands.
Great Black-backed Gull (Larus marinus) JZ923 2CY, June 29 2017, Boulogne-sur-Mer, France. Picture: Jean-Michel Sauvage. P4/P7.
Great Black-backed Gull (Larus marinus) JWN95 2CY, June 29 2017, Boulogne-sur-Mer, France. Picture: Jean-Michel Sauvage. P6/P9.
Great
Black-backed Gull (Larus marinus) NOS 392988 June 03-04 2012, Boulogne / Mer, France. Picture Jean Michel Sauvage. Also reported in August 2012.
Great
Black-backed Gull (Larus marinus) 2cy 62G June 07 2011, Boulogne / Mer, France. Picture Jean Michel Sauvage.
Great Black-backed Gull (Larus marinus) AFC 2CY, June 2012, Sable Island, NS. Picture: Sable Island banding team.
Great Black-backed Gull (Larus marinus) 1VU 1CY-3CY, November 2013 -July 2015, near Dublin, Ireland. Picture: Graham Prole.
Great Black-backed Gull (Larus marinus) 3AL 1CY-2CY, October 2013 - June 2014, near Dublin, Ireland. Picture: Stephen Lawlor, Ronnie Martin & Graham Prole.
Great Black-backed Gull (Larus marinus) 3HK 1CY-2CY, December 2013 & June 2014, near Dublin, Ireland. Picture: Graham Prole.
Great Black-backed Gull (Larus marinus) 2cy, June 10 2013, Noordwijk, the Netherlands.
Great Black-backed Gull (Larus marinus) 2cy, June 08 2013, Noordwijk, the Netherlands.
Great Black-backed Gull (Larus marinus) 2CY, June 06 2016, Katwijk, the Netherlands.
Great Black-backed Gull (Larus marinus) 2cy, June 16 2013, Noordwijk, the Netherlands.
Great Black-backed Gull (Larus marinus) 2cy, June 16 2013, Noordwijk, the Netherlands.
Great
Black-backed Gull
(Larus marinus) 2cy: June 14 2002, Le
Portel - Boulogne sur Mer, France (50.42 N - 01.34
E). Primary moult stage: P6 as long as P5 and P8 missing.
Great
Black-backed Gull
(Larus marinus) 2cy: June 14 2002, Le
Portel - Boulogne sur Mer, France (50.42 N - 01.34
E). Two images. Primary moult stage: P7 missing. Tail still completely juvenile.
Great
Black-backed Gull
(Larus marinus) 2cy: June 14 2002, Le
Portel - Boulogne sur Mer, France (50.42 N - 01.34
E). Most of the wing-coverts have been replaced for second generation
feathers.
Great
Black-backed Gull
(Larus marinus) 2cy: June 14 2002, Le
Portel - Boulogne sur Mer, France (50.42 N - 01.34
E). Primary moult stage: P7 missing.
Great
Black-backed Gull
(Larus marinus) 2cy: June 14 2002, Le
Portel - Boulogne sur Mer, France (50.42 N - 01.34
E). A delayed moulting bird with P5 missing and rectrices R1 replaced.
Great
Black-backed Gull
(Larus marinus) 2cy: June 14 2002, Le
Portel - Boulogne sur Mer, France (50.42 N - 01.34
E). A 2cy moulting the rectrices.
Great
Black-backed Gull
(Larus marinus) 2cy: June 14 2002, Le
Portel - Boulogne sur Mer, France (50.42 N - 01.34
E). Two images. A 2cy moulting the rectrices and P8 still juvenile.
Great
Black-backed Gull
(Larus marinus) 2cy: June 23 2003, IJmuiden, the
Netherlands (52.27 N - 04.33
E). A 2cy moulting the rectrices and P5 fully grown.
Great
Black-backed Gull
(Larus marinus) 2cy: June 23 2003, IJmuiden, the
Netherlands (52.27 N - 04.33
E). Two images. A 2cy with P7-P10 still juvenile.
Great
Black-backed Gull
(Larus marinus) 2cy: June 23 2003, IJmuiden, the
Netherlands (52.27 N - 04.33
E). A 2cy moulting the rectrices and P8-P10 still juvenile.
Great
Black-backed Gull
(Larus marinus) 2cy: June 23 2003, IJmuiden, the
Netherlands (52.27 N - 04.33
E). Two images. A 2cy with P7-P10 still juvenile.