Herring Gull- Zilvermeeuw (argentatus & argenteus)

(last update: December 15, 2011 )

Herring Gull - 3cy March

50 shades of grey - upperpart grey tones in gulls

Googling 'shades of grey', gulls may not be the first images turning up on your screen, and in fact and to much surprise, there may not be too many gulls in the story of the bestselling book. Still, the pictures are catching, even for the Dutch larophile and may juice the story below.
Several Nearctic species have been recorded in The Netherlands, like Ring-billed Gull, Bonapartes Gull and Franklin's Gull. Which species can be expected next? And which plumage may be the most rewarded to look for? Based on sightings of rare gulls in the Western Palearctic a list of species was created and birds were assigned to 5 groups. Every group contains rare species together with the most similar looking common species.

Group 1
Common Gull - Mew Gull - Ring-billed Gull

Group 2
Thayer’s Gull - Kumlien’s Gull - Iceland Gull

Group 3
Great Black-backed Gull - Kelp Gull - Slaty-backed Gull

Group 4
Glaucous-winged Gull - Glaucous Gull

Group 5
Herring Gull - American Herring Gull - Vega Gull

Group 3 50 shades of grey: Great Black-backed Gull - Kelp Gull - Slaty-backed Gull

Great Black-backed Gull marinus is a common gull in The Netherlands from late summer to late spring, with several immature birds oversummering. It is the largest and bulkiest of gulls, and especially males look very strong and powerful, with small dark beady eyes and huge bill. They are dominant in hierarchy when fish left-overs are spilled in harbours and simply impress Herring Gulls and other taxa with their low, guttering long-calls. Two slightly smaller species have been observed in the W.P. in just a handful of records: Kelp Gull dominicanus from southern Africa and Slaty-backed Gull schistisagus from eastern Russia. Both are smaller, Slaty-backed Gull being more compact and seen as a lone gull without direct reference, close to marinus, Kelp Gull is more elegant and well-proportioned, but in their very blackish upperparts close to marinus.

1st CYCLE GREAT BLACK-BACKED GULL VS SLATY-BACKED GULL

When observed well, very easily told apart by uppertail coverts and tail pattern. Great Black-backed Gull has only a narrow tail-band and just single chevron-like markings on uppertail coverts, leaving a very whitish rump area. On the contrary, Slaty-backed has an almost entirely dark tail and very densely barred uppertail coverts and this pattern more or less continue on the back, so there is no pale impression at all.

Great Black-backed Gull (marinus) 1st cycle JM07 March 05 2007, IJmuiden, the Netherlands (Mars Muusse). Probably male, banded in Norway. Note white barring in greater coverts.

Slaty-backed Gull (schistisagus) 1st cycle, February 13 2013, Rausu, Japan (Mike Buckland). Bulky bird. Few upper scapulars replaced. Simple tertial pattern.

Great Black-backed Gull (marinus) 1st cycle RUM ES00827010 February 08 2011, Scheveningen, the Netherlands (Mars Muusse). Banded in Russia (68°N). Chequered GC and more contrast in wing-coverts than in same aged Slaty-backed Gull. Slaty-backed Gull (schistisagus) 1st cycle, February 13 2013, Rausu, Japan (Mike Buckland). Bulky bird. Few upper scapulars replaced. Simple tertial pattern. Note skirt. Overall somewhat faded brown colour.

Great Black-backed Gull (marinus) 1st cycle JW999 April 24 2012, Boulogne-sur-Mer, France (Jean-Michel Sauvage). From Denmark, end of partial spring moult, lacking obvious large grey patches on breast or flanks.

Slaty-backed Gull (schistisagus) 1st cycle, March 16 2013, Choshi-shi, Japan. Picture: Dan Yambaru. Bulky bird. Scapulars rather plain grey. Much of underparts replaced as well.
Great Black-backed Gull (marinus) 1st cycle, December 15 2012, IJmuiden, the Netherlands (Mars Muusse). Whitish by narrow tail band, much proximal white on rectrices and emphasized by almost clean white uppertail coverts. Slaty-backed Gull (schistisagus) 1st cycle, December 27 2009 - January 04 2010, Choshi, Japan (Chris Gibbins). Bulky bird. Uniform primaries (with none of the strong patterning (spots, bars) so evident in P1-5 of Vega and Herring Gulls of this age) and uniform greater coverts. Plain tertials and simply patterned second generation scapulars.
Great Black-backed Gull (marinus) 1st cycle JH752 January 09 2012, Scheveningen, the Netherlands (Mars Muusse). Bird from N Norway (69°N), largely juvenile plumage. Note limited black in tail and widely spaced uppertail coverts. Slaty-backed Gull (schistisagus) 1st cycle, December 27 2009 - January 04 2010, Choshi, Japan (Chris Gibbins). Bulky bird. Smithsonianus-like rump and tail pattern, uniform primaries and uniform panel formed by the greater coverts. The underwing coverts are very uniform, softly patterned with brown.
Great Black-backed Gull (marinus) 1st cycle JH092 November 06 2010, Westkapelle, The Netherlands (Ies Meulmeester). From S Norway. Note limited black in tail and widely spaced uppertail coverts. Slaty-backed Gull (schistisagus) 1st cycle, December 27 2009 - January 04 2010, Choshi, Japan (Chris Gibbins). Uniform primaries with none of the strong patterning (spots, bars) so evident in P1-5 of Vega and Herring Gulls of this age, and the uniform panel formed by the greater coverts.

1st CYCLE LESSER BLACK-BACKED GULL VS KELP GULL

These two species may be very similar, but here the timing of the moult process is important. Kelp Gulls, living on the southern hemisphere hatch in November and are very fresh juveniles in January. By June-July they are about 1/2 year old and finished the post-juvenile moult. They will not start shedding inner primaries (initiate complete moult) before October.
Of course, the complete moult in graellsii and intermedius Lesser Black-backed Gull is evident in the summer months. The June and July pictures below show obvious moult gaps in central primaries, with the inner ones replaced for 2nd gen feathers and the outer primaries still old juvenile, worn and bleached. By July quite some birds show tail feather moult as well.

Lesser Black-backed Gull 2CY, July 18 2013, Katwijk, the Netherlands (Mars Muusse). Bird in complete moult: P5/P8. Central GC growing, GC6-GC8 which are the last to be replaced in a common moult strategy. S1 growing and S2 about to be shed. Within the next week, the outer secondaries will be dropped almost simultaneously, in small groups so leaving a large moult gap in this feather tract in summer. All rectrices, except R5, misisng and growing. Kelp Gull dominicanus 1st cycle, July 25 2007, South Africa. Picture: Graham Ekins. African taxon vetula. Some resemblance to Lesser Black-backed Gull. Note timing of complete moult in S Hemisphere gulls: by July still no sign of complete moult (birds only 1/2 year old now) and just finished the post-juvenile moult, including inner GC, inner MC, inner LLC and upper TT. Lesser Black-backed Gull intermedius and definitely graellsii would be in active complete moult.

Lesser Black-backed Gull DEH 4279xxx 2cy, June 24 2013, Noordwijk, the Netherlands (Mars Muusse). From N Germany Wadden Isles. In resting birds, complete moult indicated by new median coverts and many moult gaps in covert rows.

Kelp Gull (dominicanus) 1st cycle, June 26 - July 06 2013, SW Cape Province of South Africa. Picture: Chris Gibbins. African taxon vetula. Pale undertail coverts. Some resemblance to Lesser Black-backed Gull.

Lesser Black-backed Gull 2cy, June 24 2013, Noordwijk, the Netherlands (Mars Muusse). Graellsii-like bird with limited moult on winter grounds. By June tail and secondaries still juvenile. Complete moult started, P2/P5 and new MC growing in.

Kelp Gull (dominicanus) 1st cycle, June 26 - July 06 2013, SW Cape Province of South Africa. Picture: Chris Gibbins. African taxon vetula. All dark tail contrast with pale uppertail coverts. Dark inner primaries resemble Lesser Black-backed Gull. Note replaced inner coverts.

2nd CYCLE GREAT BLACK-BACKED GULL VS SLATY-BACKED GULL

When observed well, easily told apart by covert pattern and tail pattern. Great Black-backed Gull has chequered coverts, deeply notched fringes. Slaty-backed has very plain coverts, and although pale fringed, the covert area give a 'single panel' impression, either dark or pale.
Great Black-backed Gull very often has an obvious mirror on 2nd gen P10.

Great Black-backed Gull (marinus) 2nd cycle RUM ES00827010 November 28 2011, Scheveningen, the Netherlands (Mars Muusse). Banded in Murmansk, Russia (68°N). Single fresh scaps show dark upperpart colour of adult plumage.

Slaty-backed Gull (schistisagus) 2nd cycle, February 13 2013, Rausu, Japan (Mike Buckland). Pale bird on underparts and head. Fresh scapulars indicate upperpart colour of adult plumage.

Great Black-backed Gull (marinus) 2nd cycle JX260 November 01 2013, Boulogne-sur-Mer, France (Jean-Michel Sauvage). From N Norway (69°N), note chequered pattern on coverts, especially MC.

Slaty-backed Gull (schistisagus) 2nd cycle, February 13 2013, Rausu, Japan (Mike Buckland). Pale bird on underparts and head. 2nd gen tail with much dark. Note skirt.
Great Black-backed Gull (marinus) 2nd cycle, January 13 2012, IJmuiden, the Netherlands (Mars Muusse). Bulky bird with small beady eye. Much contrasting barring on all coverts. Note much vermiculation on tertial centres. Markings on head and neck more like fine linings, not mottled. Slaty-backed Gull (schistisagus) 2nd cycle, January 02 2010, Choshi, Japan (Chris Gibbins). Tail largely dark and pattern on wing-coverts very simple, plain pale brown with dark shaft or dark triangle centre. Note strong bill and very central placed eye in the head. Pale iris and faded brown primaries.
Great Black-backed Gull (marinus) 2nd cycle, December 15 2012, IJmuiden, The Netherlands (Mars Muusse). Showing vermiculated pattern on largely white tail. Slaty-backed Gull (schistisagus) 2nd cycle, January 02 2010, Choshi, Japan (Chris Gibbins). Some scapulars show the adult upperpart grey tone, matching intermedius Lesser Black-backed Gull.

Great Black-backed Gull (marinus) 2nd cycle H70T December 15 2012, IJmuiden, The Netherlands (Mars Muusse). Banded in Germany. Powerful bird with some blackish scapulars. 2nd cycle marinus often has P10 mirror.

Slaty-backed Gull (schistisagus) 2nd cycle, February 13 2013, Rausu, Japan (Mike Buckland). Dark bird on underparts and head. Fresh scapulars indicate upperpart colour of adult plumage. 2nd gen flight feathers with much dark in tail.

Great Black-backed Gull (marinus) 3rd cycle, December 15 2012, IJmuiden, The Netherlands (Mars Muusse). Large mirror on P10, but immature patterns on lesser coverts and central greater coverts. White tail. Much black on bill. Slaty-backed Gull (schistisagus) 3rd cycle, January 02 2010, Choshi, Japan (Chris Gibbins). Upperpart grey tone as in Lesser Black-backed Gull, clean yellow iris, and almost completely white tail. Mirror on P10. Note very broad white tips of tertials, which continues on the tips of the secondaries.

IMMATURE AND ADULT GREAT BLACK-BACKED GULL VS KELP GULL

Blacksih upperparts and thick bill in Kelp Gull give it a Great Black-backed Gull impression. Kelp Gull is quick in attaining a dark saddle, where Great Black-Backed Gull keep anchor-patterned scapulars for a prolonged period.
Also, Kelp Gull remain to show very limited white in the primaries (either the tips and the mirror, see picture below), while Great Black-backed Gull quickly develop a mirror on P10 (in 2nd gen P10) and normally develop large white tips, even obvious on outermost primaries in some immature birds.
A very small mirror on P10 and absence of a P9 mirror in adult Kelp Gull give it a completely different wingtip impression when compared to adult Great Black-backed (which has a merged mirrro and white tip on P10 and always a very large mirror on P9 as well in adult plumage).

Great Black-backed Gull (marinus) 2nd cycle, February 02 2012, IJmuiden, the Netherlands (Mars Muusse). No blackish saddle. 2nd gen primaries with rounded pale tips. Limited black in tail. Chequered coverts.

Kelp Gull dominicanus 2nd cycle, September 24 2011, Lima, Peru (John Turner). Upperparts tone equals Great Black-backed Gull, but this taxon has much more black in the tail, plain brown coverts, bright yellow on bill and lacking pale primary tips.

Great Black-backed Gull (marinus) 3rd cycle JW376 November 15 2012, Boulogne-sur-Mer, France (Jean-Michel Sauvage). Already large mirrro on P10 and bold white tipped primaries in 3rd cycle (3rd gen primaries).

Kelp Gull dominicanus sub-adult, December 10 2012, Australia (Mick). Upperparts tone equals Great Black-backed Gull, but this taxon has much more black in the wingtip (marinus in this plumage would show large mirrors already). Note yellowish legs.

Great Black-backed Gull (marinus) 8CY JH0R Boulogne-sur-Mer, France (Jean-Michel Sauvage). Ringed Vest-Agder, Norway. Limited head streaking in winter, dark small beady eye, blackish upperparts, pink legs, massive bird.

Kelp Gull dominicanus adult, June 30 2007, South Africa. Picture: J. Avise. Upperparts tone equals Great Black-backed Gull, but this taxon has much more black in the wingtip, with just a tiny mirror on the outer primary. Often yellowish legs and dark iris.

Great Black-backed Gull (marinus) adult, 2009-2011, Acer Port, Israel. (Amir Ben Dov). Note very large white tips on P10 (no sub-terminal black) and on P9 (black band broken) and no black on P5. Very powerful, huge massive bill and beady eye.

Kelp Gull dominicanus adult, January 06 2012, Antarctic Peninsula (Michael Shepard).Birds on the southern hemisphere are in complete moult in our winter months. Here moult in inner primaries P1 new, P2 groiwng, P5-P10 old. Dark as marinus, but much more black in wingtip with just a small mirror on P10 and full broad band on P5.

ADULT SLATY-BACKED GULL

In adult plumage Slaty-backed Gull schistisagus have:
- upperpart grey tone dark grey as in Lesser Black-backed Gull,
- pale iris,
- streaking concentrated in hindneck,
- medium-sized mirrors on outer two primaries,
- normally with full sub-terminal bands on both P9 and P10,
- very broad white tips of tertials, which continues on the tips of the secondaries.

Lesser Black-backed Gull graellsii WC6D 5CY, January 05 2010, Madrid, Spain (Delfín González). From U.K. Upperpart grey tone as in Slaty-backed, but in jizz much more elegant and slender taxon with yellow legs. Slaty-backed Gull (schistisagus) adult, January 02 2010, Choshi, Japan (Chris Gibbins). Upperparts tone matching intermedius Lesser Black-backed Gull. Much black in wingtip.
Lesser Black-backed Gull intermedius J850 adult, January 12 2010, Madrid, Spain (Delfín González). From S Norway. Note yellow legs. Slaty-backed Gull (schistisagus) adult, January 02 2010, Choshi, Japan (Chris Gibbins). Upperparts tone matching intermedius Lesser Black-backed Gull. Much black in wingtip.
Lesser Black-backed Gull intermedius NOS 4241800 8CY, September 11 2010, Boulogne-sur/Mer, France (Jean-Michel Sauvage). From Norway (59N 05E). Overcasted conditions. Note yellow legs.

Slaty-backed Gull schistisagus adult, January 21 2011, Choshi, Japan. Picture: Stuart Price. Upperpart grey tone as in graellsii, but heavy bill, short primary projection and pinkish legs.

Great Black-backed Gull marinus NLA 6.038.628 6CY, January 13 2012, IJmuiden, the Netherlands (Mars Muusse). Much darker than Slaty-backed, with more white in wingtip.

Slaty-backed Gull schistisagus adult, January 21 2011, Choshi, Japan. Picture: Stuart Price. Paler than marinus. Often very small or no mirror on P9 and often full sub-terminal band on P10.

Great Black-backed Gull marinus adult, February 18 2007, IJmuiden, the Netherlands (Mars Muusse). Some adult marinus have pale iris, emphasizing the reddish orbital ring. Much white in wingtip.

Slaty-backed Gull schistisagus adult, January 21 2011, Choshi, Japan. Picture: Stuart Price. Commonly has heavy streaking on head and neck, limited white in wingtip, more 'snouty' head shape.

Great Black-backed Gull marinus x Herring Gull argentatus hybrid? HT-252852 4CY, November 14 2007, Kalote dump Klaipeda, Lithuania. Picture: Vytautas Pareigis. Ringed as pullus on June 26 2004 in Kuusamo, N. Finland (65.57'N 29.14'E). Recalling Slaty-backed Gull, but some differences, notably wingtip pattern. Large mirrors on outer two primaries, no sub-terminal band on P10. Not very broad white tips of tertials which is normal in Slaty-backed, where it continues on the tips of the secondaries.

Slaty-backed Gull schistisagus adult, January 21 2011, Choshi, Japan. Picture: Stuart Price. Ringed bird. Note vivid pink legs, long elongated bill, relatively small white tips on primaries and very broad white tips on tertials.

Great Black-backed Gull marinus adult, December 15 2012, IJmuiden, The Netherlands (Mars Muusse). Some marinus have much black: full sub-terminal band on P5 and small spot on P4; but note this bird still has a P10 mirror merged with the tip and large mirror on P9. P10 innerweb and outerweb are both black, no grey P10 innerweb as in Slaty-backed. Slaty-backed Gull schistisagus adult, June 21 2013, Kamchatka/Chukotka Coast, Russia. Picture: Benjamin van Doren. Sub-terminal band on P5 and P10. Black on outerweb of P8, P9 and P10 reach to primary coverts. Note strong contrast between blackish outerweb of P10 and irs greyish innerweb. Broad white trailing edge to secondaries. Large 'moons', white tongue tips on P5-P8.
Great Black-backed Gull marinus adult, January 13 2012, IJmuiden, the Netherlands (Mars Muusse). Much white in wingtip and narrow white trailing edge to secondaries. No complete band on P5, in fact many marinus have very limited black at P5. Upperpart grey tone darker than in schistisagus.

Slaty-backed Gull schistisagus adult, January 27 2011, Beijing. Picture: Terry Townshend. Upperparts tone paler than Great Black-backed Gull, and this taxon has much more black in the wingtip, in this individual just a medium-sized mirror on the outer primary P10 (and full sub-terminal band) and no mirror on P9 (but this is also for Slaty-backed not much white). Note white indents into grey on P1-P3 tips and note black on P10 runs back to greater primary coverts along outer edge, with paler innerweb. Large white tips on tertials and secondaries. String of pearls (white tongue tips) on P6-P7.

Group 1
Common Gull - Mew Gull - Ring-billed Gull

Group 2
Thayer’s Gull - Kumlien’s Gull - Iceland Gull

Group 3
Great Black-backed Gull - Kelp Gull - Slaty-backed Gull

Group 4
Glaucous-winged Gull - Glaucous Gull

Group 5
Herring Gull - American Herring Gull - Vega Gull

rings argenteus: U.K.
3cy argenteus in March, ringed in Britain. (71370 bytes)Herring Gull 3G3 3cy (argenteus), March 16 2003, Boulogne/Mer, France (50.42N,1.34E).
1cy argenteus in November, ringed in Belgium. (25637 bytes)Herring Gull A7JG 3cy (argenteus), 2011 & March-July 2012, Boulogne/Mer, France (50.42N,1.34E). Picture: J-M Sauvage.
Herring Gull (argentatus) F1HT 3CY, March 01 2014, Katwijk, the Netherlands.
adult argenteus in October, ringed in the Netherlands. (35116 bytes)Herring Gull (argenteus) 3CY BTO GR-53691 March-July 2013, Calais, NW France. Picture: Jean-Michel Sauvage.
rings argenteus: France
3cy argenteus in March, ringed in France. (54539 bytes)Herring Gull DA 228127 3cy (argenteus), March 16 2003, Boulogne/Mer, France (50.42N,1.34E).
rings argenteus: Belgium
3cy argenteus in March, ringed in Belgium. (61218 bytes)Herring Gull H-112486 3cy (argenteus), March 16 2003, Boulogne/Mer, France (50.42N,1.34E).
3cy argenteus in March, ringed in Belgium. (68863 bytes)Herring Gull H-113894 3cy (argenteus), March 17 2003, Boulogne/Mer, France (50.42N,1.34E).
3cy argenteus in March, ringed in Belgium. (77228 bytes)Herring Gull H-117748 3cy (argenteus), March 15 2003, Boulogne/Mer, France (50.42N,1.34E).
3cy argenteus in March, ringed in Belgium. (56595 bytes)Herring Gull H-117774 3cy (argenteus), March 16 2003, Boulogne/Mer, France (50.42N,1.34E).
3cy argenteus in March, ringed in Belgium. (66449 bytes)Herring Gull H-117858 3cy (argenteus), March 16 2003, Boulogne/Mer, France (50.42N,1.34E).
3cy argenteus in March, ringed in Belgium. (68654 bytes)Herring Gull H-120600 3cy (argenteus), March 17 2003, Boulogne/Mer, France (50.42N,1.34E).
3cy argenteus in March, ringed in Belgium. (73713 bytes)Herring Gull H-124999 3cy (argenteus), March 29 2004, Westkapelle, the Netherlands (51.33N - 03.25E). Picture Pim Wolf.
3cy argenteus in March, ringed in Belgium. (81330 bytes)Herring Gull H-127138 3cy (argenteus), March 29 2004, Westkapelle, the Netherlands (51.33N - 03.25E). Picture Pim Wolf.
rings argenteus: Netherlands
3cy argenteus in March, ringed in the Netherlands. (72801 bytes)Herring Gull 5.352.714 3cy (argenteus), March 17 2003, Boulogne/Mer, France (50.42N,1.34E).
3cy argenteus in March, ringed in the Netherlands. (80024 bytes)Herring Gull 5.412.501 3cy (argenteus), March 20 2004, IJmuiden, the Netherlands (52.27N 04.33E). 
rings argentatus: Helgoland / Germany
3cy argenteus in March, ringed in Germany. (70068 bytes)Herring Gull 4xxx 3cy (argenteus), March 05 2004, Amsterdam, the Netherlands (52.21N - 04.52E). Picture Ruud Altenburg.
rings argentatus: Russia
1cy argenteus in November, ringed in Belgium. (25637 bytes)Herring Gull KV48 3cy (argentatus), March 2008, Boulogne/Mer, France.
unringed 3cy Herring Gulls
possible Viking Gull (argentatus x hyperboreus) 3CY, March 10 2014, Katwijk, the Netherlands. Picture: Mariska de Graaff & Mars Muusse. Difficult to draw a line between 'pale end' Herring and hybrids.
3cy argentatus in January. (80207 bytes)Herring Gull 3CY, March 21 2013, Noordwijk, the Netherlands.
3cy argentatus in January. (80207 bytes)Herring Gull 3CY, March 21 2013, Noordwijk, the Netherlands.
3cy argentatus in January. (80207 bytes)Herring Gull 3CY, March 21 2013, Noordwijk, the Netherlands.
3cy argentatus in January. (80207 bytes)Herring Gull 3CY, March 13 2013, Noordwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
3cy argentatus in January. (80207 bytes)Herring Gull 3CY, March 21 2013, Noordwijk, the Netherlands.
Herring Gull 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull (argenteus) 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull (argentatus) 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull (argentatus) 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull (argentatus) 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull (argentatus) 3CY, March 01 2014, Katwijk, the Netherlands.
Herring Gull (argentatus) 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull (argentatus) 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull (argentatus) 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 05 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 10 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 10 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 10 2014, Katwijk, the Netherlands.
Herring Gull 3CY, March 01 2014, Katwijk, the Netherlands.
3cy argenteus in January, ringed in the Netherlands. (68274 bytes)Herring Gull 3cy (argenteus), March 09 2010, IJmuiden, the Netherlands (52.27N 04.33E). 
3cy argentatus in March. (62599 bytes)Herring Gull 3cy (argentatus), March 17 2003, Boulogne/Mer, France (50.42N,1.34E).
3cy argentatus in March. (71102 bytes)Herring Gull 3cy (argentatus), March 17 2003, Boulogne/Mer, France (50.42N,1.34E).