Great Black-backed Gull (Larus marinus)
(last update: July 12, 2015)
Great Black-backed Gull 3cy December
Plumage variation in 3CY and 4CY marinus for period September-December.
3CY BIRDS
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| Larus marinus 3CY JH617, October 04 2013, Boulogne-sur-Mer, France (Jean-Michel Sauvage). Ringed as pullus in 2011 in Norway. Retarded looking bird with many barred coverts. Combined with adult-like central primaries with bold white tips on P5-P6. | Larus marinus 3CY, September 20 2015, IJmuiden, the Netherlands (Mars Muusse). Typical combination of adult-like new 3rd gen secondaries and many immature marked coverts and black in 3rd gen tail. In 2CY birds the new P10 has an indistinct mirror; here, in 3rd gen P10 the mirror is sharply borbered and normally with a full sub-terminal band (which will no longer be present in 4th gen P10). |
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| Larus marinus NLA7105682 3CY, September 24 2014, Boulogne-sur-Mer, France (Jean-Michel Sauvage). Ringed as pullus in 2012 in the Netherlands. Adult like pattern on central primaries indication too advanced for 2nd gen; small tips on P7-P9 far too small for 4CY birds. Several barred coverts. | Larus marinus 3CY, September 24 2015, IJmuiden, the Netherlands (Mars Muusse). Typical combination of adult-like new 3rd gen secondaries and many immature marked coverts and black in 3rd gen tail. 3rd gen P10 has the mirror sharply borbered and with a full sub-terminal band. |
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| Larus marinus 1LC 3CY, November 02 2013, Dublin, Ireland (Graham Prole). Ringed as pullus in 2011 in Ireland. Bold white tips on all outer primaries and adult-like secondaries. Still faded brown hue on many coverts. | Larus marinus 3CY, December 20 2014, IJmuiden, the Netherlands (Mars Muusse). Adult-like secondaries, inner and central primaries. Still, many immature patterned coverts and less white in wing tip (P6-P10) than full adults have, e.g. this bird has full subterminal band on P10. |
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| Larus marinus DKC3092175 3CY, September 24 2012, Boulogne-sur-Mer, France (Jean-Michel Sauvage). Ringed as pullus in 2010 in Denmark. Advanced plumage, with very bold white tips on outer primaries and almost completely jet-black plumage very like 4CY birds. Much black on bill but this still may match 4CY birds. | Larus marinus 3CY, December 20 2014, IJmuiden, the Netherlands (Mars Muusse). Adult-like secondaries, adult-like inner and central primaries and mirror on P9 and P10. Still, many immature patterned coverts and less white in wing tip than full adults have. |
4CY BIRDS
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| Larus marinus JZ84 4CY, September 10 2010, Westkapelle, the Netherlands (Theo Muusse). Ringed as pullus in 2007 in Norway. By September, old flight feathers are useful for ageing: adult-like old P9 and P10 should be 3rd gen, combined with black in the old tail and some brown coverts. | Larus marinus 4CY, September 20 2015, IJmuiden, the Netherlands (Mars Muusse). By September, old flight feathers are useful for ageing: old 3rd gen P10 with large white tip. Still some brown coverts. Black on bill. |
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| Larus marinus DKC3092175 4CY, November 22 2013, Boulogne-sur-Mer, France (Jean-Michel Sauvage). Adult-like with obvious black on the bill. | Larus marinus 4CY, December 20 2014, IJmuiden, the Netherlands (Mars Muusse). Adult-like with single brown coverts (see underwing). |
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| Larus marinus JE580 4CY, October 04 2013, Boulogne-sur-Mer, France (Jean-Michel Sauvage). Ringed as pullus in 2010 in Norway. Moult score: P7/-. Full band on the bill. | Larus marinus 4CY, December 20 2014, IJmuiden, the Netherlands (Mars Muusse). Large mirrors on P9 and P10. Several brown coverts and broad bill-band. |
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| Larus marinus 76D 4CY, November 15 2012, Boulogne-sur-Mer, France (Jean-Michel Sauvage). Ringed as pullus in 2009 in France. Much adult-like in plumage. This limited black on the bill is no safe criterion for ageing, also occurs in mature birds. | Larus marinus 4CY, December 20 2014, IJmuiden, the Netherlands (Mars Muusse). Adult-like with single brown coverts (see underwing) and most obvious broad bill band. Immature birds have a tendency to develop more streaking on head and breast than wintering adults do. |
Great
Black-backed Gull (Larus marinus) 3cy E703 December 14 2003, Westkapelle, the Netherlands. Ringed in 2001, erschelling, the Netherlands.
Great Black-backed Gull (Larus marinus) JT425 2nd-3rd cycle (2CY-3CY), October - December 2014 & December 2015, the Netherlands.
Great Black-backed Gull (Larus marinus) JZ413 2CY-4CY, February 2015 - February 2017, IJmuiden, the Netherlands.
Great Black-backed Gull (Larus marinus) 3CY, December 26 2016, IJmuiden, the Netherlands.
Great Black-backed Gull (Larus marinus) 3CY, December 26 2016, IJmuiden, the Netherlands.
Great Black-backed Gull (Larus marinus) 3CY, December 26 2016, IJmuiden, the Netherlands.
Great Black-backed Gull (Larus marinus) sub-adult, December 26 2016, IJmuiden, the Netherlands.
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Black-backed Gull (L. marinus) 3cy: December 15 2012, IJmuiden, The Netherlands.
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Black-backed Gull (L. marinus) 3cy: December 20 2014, IJmuiden, The Netherlands.
Great Black-backed Gull (Larus marinus) 3CY, December 03 2015, IJmuiden, the Netherlands.
Great Black-backed Gull (Larus marinus) 3CY, December 03 2015, IJmuiden, the Netherlands.
Great Black-backed Gull (Larus marinus) 3CY, December 03 2015, IJmuiden, the Netherlands.
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Black-backed Gull (L. marinus) 3cy: December 20 2014, IJmuiden, The Netherlands.
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Black-backed Gull (L. marinus) 3cy: December 20 2014, IJmuiden, The Netherlands.
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Black-backed Gull (L. marinus) 3cy: December 15 2012, IJmuiden, The Netherlands. Large mirror on P10, but also sub-terminal black on P10.
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Black-backed Gull (L. marinus) 3cy: December 15 2012, IJmuiden, The Netherlands. Showing underwing. Large mirror on P10, but also sub-terminal band on P10.
Great Black-backed Gull (Larus marinus) 3CY, December 26 2016, IJmuiden, the Netherlands.
Great Black-backed Gull (Larus marinus) 3CY, December 26 2016, IJmuiden, the Netherlands.
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Black-backed Gull (L. marinus) 3cy: December 20 2014, IJmuiden, The Netherlands.
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Black-backed Gull (L. marinus) 3cy: December 15 2012, IJmuiden, The Netherlands. Large mirror on P10, but immature patterns on lesser coverts and central greater coverts. White tail. Much black on bill.
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Black-backed Gull (L. marinus) 3cy: December 15 2012, IJmuiden, The Netherlands. Large mirror on P10, but also sub-terminal band on P10.
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Black-backed Gull (L. marinus) 3cy: December 15 2012, IJmuiden, The Netherlands. Large mirror on P10, but immature patterns on inner coverts. Much black on bill.
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Black-backed Gull (L. marinus) 3cy: December 15 2011, Scheveningen, The Netherlands.