Great Black-backed Gull (Larus marinus)

(last update: July 12, 2015)

Coordinators:
Jean-Michel Sauvage (France)
Morten Helberg (Norway)
Nils Helge Lorentzen (Norway)
Mars Muusse (Netherlands)

Great Black-backed Gull 1cy December

top: marinus 1cy, December 15 2012, IJmuiden, The Netherlands. Picture: Mars Muusse. Classic tail-pattern with much proximal white on the outer rectrices and the sub-terminal band hardly reaching the outer-web of R6. Pale inner primaries and pale 'lozenges' on th eouter-webs of P1-P4, the prominence of the pale window depends on the relative angle of the wing.
below: marinus 1cy, December 15 2012, IJmuiden, The Netherlands. Picture: Mars Muusse. Some individuals have rather dark inner primaries, lacking an obvious pale window, especially when the wing is half-folded.

Moult into first winter

Juvenile moult to first winter plumage partial Aug-Nov, including mantle, scapulars, and (probably) parts of head and body. Often no sign of moult into Nov/Dec. (Malling Olsen, K. & Larsson, H. 2004 Gulls of Europe, Asia and North America. London: Christopher Helm).

Although Malling Olssen states "often no sign of moult into Nov/Dec", this is not supported by data of ringed birds. The table presented in September illustrates that already 40% (n = 10) do show the first signs of moult, i.e. new upper scapulars. By November, over 90% (n = 45) replace the upper scapulars and 75% has started moult in the lower scapulars as well.

By November, all ringed birds (except for 3EN blue from Ireland) had at least some new upper scapulars, with the majority of birds categorised ">75% of the upper scpaulars replaced". There may be a bias towards southern populations, as many images on this site are from birds ringed in S Norway or colonies further south like Denmark and France. It remains pure speculation, but it would be interesting to know where very fresh juvenile birds in November, like THIS ONE hatched. Birds similar to this one, but still fresh by 2cy March, are represented by THIS POWERFULL bird, which is believed to have travelled from far northern Europe. A far northern hatching colony does not necessarily reflect late moult in scapulars. In February we photographed this Russian bird from Murmansk, with quite average moult scores in the scapulars.

Despite its southern hatching location, this 1cy bird black JJ77, showed only very limited scapular moult by December, and from all 8 ringed birds in December, it was obviously most retarded.

top: marinus 2cy, February 02 2012, IJmuiden, The Netherlands. Picture: Mars Muusse. February, and still the vast majority of scpaulars juvenile, only single upper scapulars replaced. In W Europe, we may have northern Herring Gull argentatus and northern Great Black-backed Gull marinus from mid-October onwards. Their origins are N Norway (up to 70" N) and Russian White Sea (65" N), and we think those are the locations where these 'retarded moulting' juveniles come from. There are several birds on this site that have the fringes of the juvenile scapulars even in better condition than this bird above, even in late winte (February).
below: marinus 2cy RUM ES008270, February 01 2011, Scheveningen, the Netherlands. Picture: Mars Muusse. Bird from N Russia (68°46'59 N, 37°25'0E). Despite the northern origin, almost all scapulars replaced.
below: marinus 2cy JA911 February 27 2009, Fraserburgh, Scotland. Picture: Mars Muusse. You won't get them from much further north in Europe, hatched Hornøya, Vardø, Finnmark, Norway (70°23'16"N 031°09'21"E). Most upper scapulars replaced by late February.

Tables:

Moult in 1cy December GBBG - ringed birds.
CODE  
US
LS
TOT SCAPS
32n black france december 0 0 0
j431w black denmark december 1 1 1
jj77 black norway december 1 0 1
jt181 black norway december 1 0 1
3hk blue britain december 3 0 1
j45a blue norway december 3 0 2
ju818 black norway december 3 1 2
hm32 red germany december 4 1 2
jp086 black norway december 4 2 3
ju137 black norway december 4 1 3
ju161 black norway december 4 2 3
ju754 black norway december 4 1 3
ju758 black norway december 4 3 3
1u5 black usa december 4 2 3
6v5 black usa december 5 2 3
8j4 black usa december 4 3 3
jc2z blue norway december 5 4 4
jp140 black norway december 5 4 4
jp919 black norway december 4 4 4
jl25 black norway december 4 3 4
nos 3020837 norway december 4 3 4
ju137 black norway december 4 3 4
dkc 3099223 denmark december 5 3 4

below: graph corresponding to data from table 1. n=23. Distribution of replaced scapulars in December 1cy GBBG, separated into Upper Scapulars, Lower scapulars and for Total scapular region. Classification in 6 classes, running from 0% (no 2nd gen scaps) to 100% (all scaps in a region have been replaced).

It is clear from the column "Total scapulars" that less than 10% of the ringed December birds scored "0% 2nd gen scaps" (only 1 out of 22 ringed birds was still in completely juvenile plumage), in other words, the other 90+% of those 22 ringed birds had replaced at least one or more (upper) scapulars for 2nd gen feathers.

below: Great Black-backed Gull JA804 illustrates differences in colour and pattern between old juvenile 1st generation scapulars and fresh buffish 2nd generation feathers. Bird ringed as pullus on June 12 2012 at Salvøy, Karmøy, Rogaland, Norway (59°17'54"N 005°12'27"E). Picture: Jean-Michel Sauvage, September 28 2012, Boulogne-sur-Mer, NW France.

below: Distribution of replaced scapulars for "Total scapular region" for months August in hatch year until commencement of first complete moult in April. Classification in 6 classes, running from 0% (no 2nd gen scaps) to 100% (all scaps, including long rear scaps, have been replaced). Only ringed birds, n=238.

Origin of all 191 ringed bird, used in our sample. Several individual birds observed in more than one month.
britain
13
denmark
25
france
19
germany
3
holland
3
norway
115
russia
2
sweden
1
usa
10

ring projects Norway & Denmark:

7343j45a.jpg (60037 bytes)Great Black-backed Gull (L. marinus) 1cy J45A December 14 2002, Westkapelle, the Netherlands (51.33 N, 03.25 E).
1598.jpg (74227 bytes)Great Black-backed Gull (L. marinus) 1cy JC2Z December 26 2006, Boulogne/Mer, France. Picture: J-M Sauvage.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (L. marinus) 1cy J431W December 01 2011, Boulogne sur Mer, France (50.44 N - 01.35 E). Picture Jean-Michel Sauvage.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (L. marinus) 1cy JA760 December 31 2009, Boulogne sur Mer, France (50.44 N - 01.35 E). Picture Jean-Michel Sauvage.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (L. marinus) 1cy JP086 December 04 2011, Boulogne sur Mer, France (50.44 N - 01.35 E). Picture Jean-Michel Sauvage.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (L. marinus) 1cy JP140 December 04 2011, Boulogne sur Mer, France (50.44 N - 01.35 E). Picture Jean-Michel Sauvage.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (L. marinus) 1cy JP919 December 04 2012, Boulogne sur Mer, France (50.44 N - 01.35 E). Picture Jean-Michel Sauvage.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (Larus marinus) JT181 1st cycle (1CY), December 20 2014, IJmuiden, the Netherlands.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (Larus marinus) JU137 1st cycle, December 2014 & February 2015, IJmuiden, the Netherlands.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (Larus marinus) JU161 1st cycle (1CY-2CY), December 20 2014 & April 05 2015, IJmuiden, the Netherlands.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (Larus marinus) JU754 1st cycle (1CY), December 20 2014, IJmuiden, the Netherlands.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (Larus marinus) JU758 1st cycle (1CY), December 20 2014, IJmuiden, the Netherlands.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (Larus marinus) JU818 1st cycle (1CY-2CY), December 20 2014 & February 19 2015 , IJmuiden, the Netherlands.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (Larus marinus) JYJ32 1cy: December 04 2013, Vlissingen, the Netherlands. Picture: Jan Goedbloed.
1598.jpg (74227 bytes)Great Black-backed Gull (L. marinus) 1cy JL25 December 29 2006, Boulogne/Mer, France. Picture: J-M Sauvage.
1598.jpg (74227 bytes)Great Black-backed Gull (L. marinus) 1cy JJ77 December 04 2006, Boulogne/Mer, France. Picture: J-M Sauvage.
gbbgGreat Black-backed Gull (marinus) 1cy-2cy NOS 3020837 December 2011 & October 2012, Boulogne-sur-Mer, NW France. Picture: Jean-Michel Sauvage.
8471j52c.jpg (85052 bytes)Great Black-backed Gull (Larus marinus) DKC 3099223 1st cycle (1CY), December 20 2014, IJmuiden, the Netherlands.

ring project Germany:

2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (Larus marinus) HM32 1cy, December 31 2013, Boulogne sur Mer, France. Picture Jean-Michel Sauvage.

ring project France:

jz8mjan.jpg (127846 bytes)Great Black-backed Gull (Larus marinus) 32N 1cy-2cy, December 06 2013 & January 31 2014, Boulogne sur Mer, France. Picture Jean-Michel Sauvage.

ring project Ireland:

7095jp36.jpg (66909 bytes)Great Black-backed Gull (Larus marinus) 3HK 1CY-2CY, December 2013 & June 2014, near Dublin, Ireland. Picture: Graham Prole.

ring projects Appledore Island, US:

2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (Larus marinus) 1U5 1st cycle (1CY), December 29 2013, Hampton Beach, New Hampshire. Picture: Keith Mueller.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (Larus marinus) 6V5 1CY, December 01 2012, Hatteras, North Carolina. Picture: Nathan Gatto.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (Larus marinus) 8J4 1st cycle (1CY-2CY), December 2013 & January 2014, Galilee Harbor, RI. Picture: Keith Mueller.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (Larus marinus) xxx-x4585 1cy, December 24 2012, Galilee Harbor, Point Judith, Rhode Island. Picture: Keith Mueller.

unringed birds:

2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 26 2010, Waddenzee - Friesland, The Netherlands. Picture: Ted van der Knaap.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands. Probably female.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands. Probably male.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands. Relatively broad & solid tail-band.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands. Still juvenile plumage.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands. Still fresh juvenile plumage, probably from far N origin.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands. Still juvenile plumage.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2011, Scheveningen, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands. Still juvenile plumage.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands. 1cy (right) and 2cy (left); note underwing coverts and tail pattern. Adult is referee.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands. Probably male. Limited moult in scaps.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 15 2012, IJmuiden, The Netherlands. Probably male.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.
2121gbbgad.jpg (50050 bytes)Great Black-backed Gull (L. marinus) 1cy: December 20 2014, IJmuiden, The Netherlands.