Caspian Gull - Adult, Private Site, Essex 16th January 2010
Not a classic bird but the features are there:
· Slender, parallel sided pale yellow bill with dark marks on the red gonys spot and on the upper mandible above
· Small clean white head with sloping forehead
· The eye looks dark at range but is actually coffee coloured
· Mid grey upper-parts
· Slender pasty fleshy coloured legs
· Long primary projection, note P7 appears to missing thus creating a void in the wing
· Hanging rear belly.
Caspian Gull - Adult, Private Site, Essex 16th January 2010
Note:
- The lemony yellow parallel sided bill. The Gonydeal expansion is quite obvious on this bird, perhaps a male, but the bill tip tapers away.
- Darkish coffee coloured eye, appeared simply black at range
- Clean white head and under-parts, the throat is slightly extended as it had just swalled some rather unpleasant looking (see role over image on the wing spread shot below)
- Mid grey upper-parts
- Long Primary projection with large white tip to P10 and white/pale tongue extending along underside of same feather
- Long insipid grey legs
- Elongated appearance, this bird lacks the hanging belly of many typical adult Caspian Gulls
Caspian Gull - Larus cachinnans
Adults & Near Adults: page 2
Caspian Gull - Adult, Private Site, Essex, 16th January 2010
If there was ever a good adult Caspian Gull to photograph then this would be it. Note the elegant proportions; small head, proud puffed up breast, slender sloping back with no tertial step and tapering along the long primaries.
The bill is long, slender and pale lemony yellow with a dusky mark on the top of the red gonys spot and on the culman. The eye is dark and really stands out in the clean white face; the head is small with nice sloping forehead. Compare these features with the Herring Gulls at the rear.
The white tertial crescent is rather large and contrasts more strongly with the mid grey upper-parts than on the Herring Gulls at the back.
P10 has a large white tip and the white tongue that extends along the underside of the same feather is visible beyond the tips of the tertials. In life and in video footage the classic pattern could be seen during a full wing stretch.
This bird has fairly long and slender legs, though not overly so, and have a rather strong yellow cast to them. According to Olsen & Larsson about 12% of Ukranian Caspian Gulls show distinctly yellow legs so perhaps this birds has traveled from that region.
Caspian Gull - Adult, Private Site, Essex 16th January 2010
Same bird as in previous image but from this angle can now see the primary pattern well:
1: Large white mirror to P10 seperated from from the small white tip by a narrow band of black, typical of some Caspians but generally not commonly seen on the birds in south Essex for some reason.
2: Pale grey ventral tongues 'eating' into the black creating a fingered appearance
3: Large white tip to P5 with narrow black band, broader on the outer edges of both webs
4: White tongue extending along the underside of P10 almost as far as the white mirror
Also note that the black of the wing tip does not reach the greater primary coverts on P9 and P8 and then falls well short on all subsequent primaries.
Caspian Gull - Adult, Private Site, Essex 16th January 2010 Same bird as in previous image:
Here the primary pattern is obvious:
- Large white tip to P10
- Large white mirror to P9 but with the black of the outer web only extending up the feather
- Obvious pale grey tongues or ventral shafts eating into the black terminating in a white 'moon'
- Broad black band on P5
- Small dark mark on P4
Note on the left wing that there is very little black visible.
Roll over the image with the mouse to see an even wider open wing, not as sharp due to low shutter speeds at the time the picture was taken, but shows the streaked primary tip pattern.