Gulls in NW Europe
(last update: September 25, 2011
Herring Gull (?) 1cy XJCW Decembver 21 2011, Boulogne-sur-Mer, NW France. Picture: Jean-Michel Sauvage.
Bird ringed as pullus at Oberspreewald Lausutz, Brandenbourg, Germany (51.33N 14.06E) on 07 June 2011. This is a colony of mixed taxa, about 30% "argentatus" and 70% "cachinnans". There are also a few michahellis in this colony. XJCW shows features of both cachinnans and argentatus.
Distance to Boulogne: 877 Km.
Below, table 2 is repeated to score this bird. The scores are in italic + bold.
Partial score is 28 by Mars Muusse, but open for discussion, which places this bird in the hybrid zone of the spectrum.
Table 2. Traits and scores used to characterise birds in first-winter plumage (October-March inclusive).
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| Trait | Score | Description |
| Extent of scapular moult | 0 | no first-generation feathers remaining |
| 1 | a small number (<1/3) of first-generation feathers remaining | |
| 2 | a significant number (>1/3) of first-generation feathers remaining | |
| Greater-covert pattern | 0 | simple pattern with brown centres and sharp white edges, with no white vermiculation or notching |
| 1 | white edges with delicate notches or vermiculation; or dark brown centre with white tip to 1/3 of length (i.e. white restricted to tip or distal third) | |
| 2 | clear white notches / barring creating a delicate 'piano key' pattern along the whole edge / feather; but much of feather dark | |
| 3 | lots of white (more than 1/2 of coverts looking white) distributed along the whole feather, or a bold notching ('piano key' pattern) | |
| Bill shape | 0 | Very long and slim, no visible gonydeal angle (L:D ratio >2.8) |
| 1 | Slim, slight gonydeal angle (ratio 2.4-2.79) (Measured 2,66 from picture, Mars Muusse) | |
| 2 | Intermediate (ratio 2.0-2.39) | |
| 3 | Short and deep, well marked gonys angle (ratio <2) | |
| Leg length | 0 | Long and slim looking |
| 1 | Moderately long | |
| 2 | Short or short and stocky | |
| Ventral bulge | 0 | present |
| 1 | absent | |
| Primary projection | 0 | very long (ratio >0.6) (Measured >0,60 from picture, even though angle not ideal, Mars Muusse) |
| 1 | moderately long (ratio 0.5-0.59) | |
| 2 | medium (ratio 0.4-0.49) | |
| 3 | short (ratio <0.4) | |
| Moult: greater coverts | 0 | all or almost all new (>75%) |
| 1 | 51-75% new | |
| 2 | 34-50% new | |
| 3 | 10-33% new | |
| 4 | one or two feathers moulted | |
| 5 | no moult | |
| Moult: median coverts | 0 | all or almost all new (>75%) |
| 1 | 51-75% new | |
| 2 | 34-50% new | |
| 3 | 10-33% new | |
| 4 | one or two feathers moulted | |
| 5 | no moult (although 1 replaced feather in left wing) | |
| Moult: tertials | 0 | 3 or more new |
| 1 | 2 new | |
| 2 | 1 new | |
| 3 | all old | |
| Darkness of head and body | 0 | totally white |
| 1 | reduced grey wash or streaking (confined to flanks and/or single streaks around nape) | |
| 2 | light streaking/wash to head (incl. some dark around eye); isolated streaks/blotches on body. Overall, body looks more white than brown | |
| 3 | well streaked: dark mask around eye and/or streaking covering the whole head/face; body with extensive but moderately dense streaks/mottles | |
| 4 | strong and dense streaking/mottling on body and head making it appear almost wholly dark | |
| First-generation tertial pattern | 0 | diffuse white tip (like Common Gull Larus canus) |
| 1 | fine pale fringe around distal portion (like classic michahellis), possibly also with some vermiculations | |
| 2 | edges moderately notched | |
| 3 | edges strongly notched and/or some dark barring or pale patches across the feather on some or all tertials | |
| Second-generation scapular pattern | 0 | uniformly silvery-grey, darker patterning absent or very faint |
| 1 | silvery-grey background, pattern stronger than on 0, but lacks strong barring or central dark diamonds (only dark shafts and subtle anchors), with only a minority (one or two) of such feathers admixed | |
| 2 | strong, contrasting shaft-streaks, anchors and/or dark central diamonds, but these more patterned feathers are less than 1/2 of all; ground colour creamy or silvery-grey, possibly with some grey feathers mixed in | |
| 3 | strong pattern described in 2 on most (more than 1/2) of feathers, but possibly also one or two plain grey feathers or feathers with grey ground tone | |
| 4 | all feathers contrastingly patterned (with dark cross bars or diamonds), lacking plain grey feathers; feather centres buffy-brown | |
See figure 8 for position of this bird in the spectrum:
