Great Black-backed Gull (Larus marinus)

(last update: October 12, 2011)

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

Great Black-backed Gull 2cy March

Description of 1st summer plumage

First-summer (Mar-Aug) as first-winter, but head and underparts generally whiter. Mantle, back and scapulars grey with black subterminal bars and shaft-streaks. Upperwing and tail paler with wear. Bill black with smudgy, greyish- or fleshy-tinged base and pale tip to both mandibles. Eye dark. (source: Malling Olsen, K. & Larsson, H. 2004 Gulls of Europe, Asia and North America. London: Christopher Helm).

Moult in summer months.

The above description from Malling Olsen may be true for birds in March and April, but 2CY Great Black-backed Gulls in the summer months are obviously different from first-winter plumage birds.
Great Black-backed Gull is an early moulting species, at least that's what birds show that stay in NW France along The Channel coast and moult timing may even start earlier than 2CY Yellow-legged Gull michahellis (see tables in 2CY May section for marinus, michahellis and argentatus). New 2nd generation feathers may superficially resemble the old and worn juvenile feathers in pattern (transversal barring), but they are very fresh, especially visible at the fringes and the tips, and the base tone is warm buffish or pale brown rather than the silvery white tones in juvenile feathers, Only after several weeks these warm toned 2nd gen feathers will turn paler as well and become more contrasting again.

In early summer there is an obvious difference between fresh warm toned 2nd gen feathers and old bleached juvenile feathers, sometimes resulting in a messy looking bird, also due to missing feathers creating moult gaps in the covert rows. Such birds look different from first winter birds.
Later in summer (July-August) the process of complete moult is very obvious in the outer primaries and in this respect birds of course look very different from first winter birds.


Larus marinus JY481 2CY, February 10 2013, Boulogne-sur-Mer, France (Jean-Michel Sauvage). Classic late winter bird with most scapulars replaced, but wing-coverts and tertials still juvenile. Note pattern on juvenile central greater coverts: predominantly silvery white with widely spaced brown bars. Complete moult not started yet.


Larus marinus 3U4 2CY, May 27 2014, Whiting, USA (Amar Ayyash). Complete moult started early in this bird, with only P8-P10 old juevniel primaries in the left wing (P7 also still present in right wing). Note warm toned fresh 2nd gen median coverts and all central greater coverts missing. Messy looking bird.


Larus marinus 2CY, July 30 2014, IJmuiden, the Netherlands (Mars Muusse). P9-P10 old juvenile. Note vermiculated pattern on fresh 2nd gen greater coverts, different from the widely spaced bar pattern on juvenile greater coverts.


Larus marinus NOS 337783 2CY, August 14 2013, Boulogne-sur-Mer, France (Jean-Michel Sauvage). Complete moult in last stage with P7 fully grown and no old primaries left, resulting in short-winged appearance. Again, note vermiculated pattern on central greater coverts.


Larus marinus NOS 337783 2CY, November 06 2013, Boulogne-sur-Mer, France (Jean-Michel Sauvage).Same bird as previous image. Complete moult finished, note mirror on underside of P10. Compare to August, and notice a subsequent "partial autumn moult" has changed the plumage slightly, again fresh feathers appear in the wing panel. The upper tertial and innermost greater coverts GC1-2 have been replaced again; also new are median coverts MC2,10,11,13,15, and lower lesser coverts LLC1-3,6,8-12, and about 10x lesser coverts. Five of these fresh feathers indicated by red lines.

8902j43a.jpg (64885 bytes)Great Black-backed Gull J43A (Larus marinus) 2cy: March 15 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E). Picture: J-M Sauvage.
2271je1l.jpg (54308 bytes)Great Black-backed Gull JE1L (Larus marinus) 2cy: March 25 2004, IJmuiden, the Netherlands (52.27 N, 4.33 E). Juvenile coverts and tertials. Almost all scapulars moulted to second generation. Note extensive black in tail.
2247j8k0.jpg (78638 bytes)Great Black-backed Gull J8K0 (Larus marinus) 2cy: March 25 2004, IJmuiden, the Netherlands (52.27 N, 4.33 E). Juvenile coverts and tertials. Almost all scapulars moulted to second generation.
8902j43a.jpg (64885 bytes)Great Black-backed Gull J3TR (Larus marinus) 2cy: March 22-24 2008, Boulogne-sur-Mer, France (50.42 N - 01.34 E). Picture: J-M Sauvage.
8902j43a.jpg (64885 bytes)Great Black-backed Gull J1KS (Larus marinus) 2cy: March 28 2008, Boulogne-sur-Mer, France (50.42 N - 01.34 E). Picture: J-M Sauvage.
2247j8k0.jpg (78638 bytes)Great Black-backed Gull JL90 (Larus marinus) 2cy: March 05 2007, IJmuiden, the Netherlands (52.27 N, 4.33 E). Single coverts replaced. Almost all scapulars moulted to second generation.
2247j8k0.jpg (78638 bytes)Great Black-backed Gull JM07 (Larus marinus) 2cy: March 12 2007, IJmuiden, the Netherlands (52.27 N, 4.33 E). Juvenile coverts and tertials. Almost all scapulars moulted to second generation.
gbbg Great Larus marinus) 2cy JW178 March 04 2011, IJmuiden, the Netherlands.
2046nos362917.jpg (60676 bytes)Great Black-backed Gull NOS 362917 (Larus marinus) 2cy: March 20 2004, IJmuiden, the Netherlands (52.27 N, 4.33 E). Resembling a juvenile.
2247j8k0.jpg (78638 bytes)Great Black-backed Gull NLA 6.038.628 (Larus marinus) 2cy: March 05 2007, IJmuiden, the Netherlands (52.27 N, 4.33 E). Juvenile coverts and tertials. Almost all scapulars moulted to second generation.
2247j8k0.jpg (78638 bytes)Great Black-backed Gull NLA 7.024.244 (Larus marinus) 2cy: March 02 2007, Lauwersoog, the Netherlands. Picture: Martin.
7095jp36.jpg (66909 bytes)Great Black-backed Gull (Larus marinus) 3CT 1st cycle (2CY), March 09 2014, Bray Harbour, Dublin, Ireland. Picture: Graham Prole.
9101.jpg (76303 bytes)Great Black-backed Gull (Larus marinus) ACX 1st cycle (2CY), March 14 2012, Woods Harbour, NS. Picture: Barrington Detachment.
9149.jpg (76564 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 05 2007, IJmuiden, the Netherlands.
9149.jpg (76564 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 05 2007, IJmuiden, the Netherlands.
8907gbbg2cy.jpg (75608 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 15 2003, Boulogne-sur-Mer, France (50.42 N - 01.34 E). Male.
8981gbbg2cy.jpg (65986 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 16 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
8986gbbg2cy.jpg (66832 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 16 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9032gbbg2cy.jpg (72722 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 16 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9033gbbg2cy.jpg (76192 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 16 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9225gbbg2cy.jpg (73848 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 17 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9228gbbg2cy.jpg (70978 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 17 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9279gbbg2cy.jpg (71116 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 17 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9290gbbg.jpg (66389 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 17 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9292gbbg.jpg (60481 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 17 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9306gbbg.jpg (67672 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 17 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9369gbbg.jpg (57280 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 17 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9404gbbg.jpg (63107 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 17 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E).
9505gbbg.jpg (64061 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 18 2003, Boulogne- sur-Mer, France (50.42 N - 01.34 E). A very powerful and enormous male, still with most feathers fresh juvenile. Probably from far northern Scandinavia or Russia.
2032gbbg2cy.jpg (94341 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 20 2004, IJmuiden, the Netherlands (52.27 N, 4.33 E). Dark bird.
2067gbbg2cy.jpg (79048 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 20 2004, IJmuiden, the Netherlands (52.27 N, 4.33 E). Still largely juvenile, including scapulars.
2101gbbg2cy.jpg (98565 bytes)Great Black-backed Gull (Larus marinus) 2cy: March 20 2004, IJmuiden, the Netherlands (52.27 N, 4.33 E). Already a yellow bill.