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

Gulls Index Page

Home

<< Back to the top

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.

Caspian Gull , adult, Undisclosed location, Essex 8th January 2011

Initially thought to be an adult on first view this bird was subsequently aged as a fourth-winter due to the small white tips to the primaries and the dark markings to the primary coverts on outstretched wings

Note the pale pasty fleshy-pink and spindly legs; the long slender parallel edge bill with minimal Gonydeal expansion, dark looking eye set forward in small head.

Caspian Gull , adult, Undisclosed location, Essex 22nd January 2011

Adult Caspians don't come much better than this bird, both a looker and extremely confiding.

In the head shot above note:

- Bright red orbital ring

- Rather pale eye for a Caspian Gull though not staringly pale yellow as in Herring Gull; more amber coloured with dark flecks

- The long slender parallel edged bill which is pale lemony-green yellow with a paler greyish-white tip. The Gonys is fairly prominent on this bird but it was large so presumably a male.

- Shape of the nostril slit

- Red gape line turning downwards in unhappy 'clown-like' manner

- Small rounded head with the bill giving a disproportionate long face

Caspian Gull , adult, Undisclosed location, Essex 22nd January 2011

Head looks small compared with overall body size.

The grey upper-parts were a little darker and less blue than on Herring Gull. The tertials are broadly tipped white and there is no obvious tertials step. The primaries extend well beyond the tertials with large white tips and broad white tip to the underside of P10 of the far wing.

This bird had pale fleshy-yellow legs which seemed to change in tone depending on light, in the field in brighter light often looked pale greyish-pink whilst in flat nuteral light there was a distinct yellow cast.

On the image below not the underside of P10; the tips is all white with the white tongue extending well towards the mirror creating a 'waved' black band.

Caspian Gull , adult, Undisclosed location, Essex 22nd January 2011

The images here really don't reflect the overall leg length and colour; the legs which in some lights were pasty and almost greyish whilst in some others seemed yellowish, at the right angle they were also thin as would be expected though not overly long though this doesn't concern me that much as there is individual variation in this respect though most are rather lanky.

In Olson and Larsson the legs tend to be greyish with yellow to fleshy-pink tinge (rarely bright yellow). Ukranian colonies show pale or greyish-yellow (88%) to deep yellow (12%) whilst in Hungary, Aug, 2-3% are dull yellow, 12% Greyish-yellow, 61% greyish-flesh. There is no doubt though there is a distinct yellow tone to the legs. I had a similarly 'yellowish' legged bird last winter, see above, which was darker eyed.

The pale eye is a little unusual however it is not like a Herring Gulls piercing pale yellow, it is more amber coloured with dark flecking; according to Olsen and Larsson the 'Iris dark brown, dull yellow-brown or pale greyish-yellow with dark speckling'; 55% of Ukrainian breeders are 'pale' eyed with larger percentage of pale-eyed birds towards the east of the range. I recall a bird from the Midlands a few years back that was

similarly pale eyed, I'll have to see if I can find images of that bird again.

Also says that orbital ring is orange with 2-3% red though the red normally combined with dark eyes. Although pale eyed it's not as pale as on Yellow-legged or Herring Gulls so perhaps this bird is one of this small

percentage.

The gape is bright red and clearly has an unhappy Clown expression, obvious downward vector, which seems to be typical of cachinnans

The overall structure and appearance of the bird was as Caspian Gull, long slender tapering rear end, elegant proportions, lack of tertial step, small head compared with body size. It was a big bird so presumably a male. The typical pearshaped head was not apparent on this bird but again if a male this would be less obvious.

The spread wing pattern as Caspian, limited black wing tips with pale grey tonges. Large white tip to P10, large white mirror to P9, narrow band across P5.

On the face of it I would suspect this bird is of Ukranian origin though with any slightly different than the norm birds there is always the prospect of it being a hybrid, or are they just variants within the species; just look at the variety within Herring Gulls.

Move the mouse cursor over the image to highlight the key features of the wingtip pattern supporting Caspian Gull.

Caspian Gull , adult, Undisclosed location, Essex 29th January 2011

This bird was small and weak billed so is presumably a female.

The bills is slender and parallel edged and lemony yellow; the eye is typically dark; the legs are slender and insipid fleshy-pink and fairly long but not the often seen stilt like appearance of some larger birds.

The upper-parts were a tone or two darker than Herring Gull. Also note the typical pushed up breast

Addendum:

The same bird as seen on the 22nd January 2011. There is a more than distinct Caspian Gull quality to this bird but the more that I look at it a couple of features seem to suggest that it may not be completely pure bird.

The eye is quite large and fairly pale and centrally placed in the head. The size and colour is not a problem for a big, and presumably male, bird as this and as detailed above, though perhaps the positioning is a little to central in the head?

The head is a little rounded with a peak behind the eye at the rear crown and it lacks the classic sloping forehead profile. Again this probably isn't much of an issue as it is a big bird and so presumably a male which 'could' account for the slightly largish head and off classic profile.

The legs are somewhat short and yellowish, again not a show stopper in this respect as detailed above but majority of Casps seen are leggy birds. The wings here look short but given the open wing pattern this could again be accounted for if the bird is a male.

I may be being over cautious with this bird because its not a classic but if hybrid genes are at work, what genes could be influencing the Caspian blood? In the absence of any real hybrid genes at work over a non typical individual I am happy to leave this bird as a pale eyed Caspian Gull.

Caspian Gull - Adult, Undisclosed Site, Essex, 17th December 2011

This recent image has been moved to the top of the top of the page as I feel it illustrates the underwing pattern very well compared with the Herring Gull just in front of it.

Firstly note how long winged the bird appears, very long in the 'hand' as well as the shoulder to wrist. Caspians nearly always look long winged in flight.

Now compare the underwing pattern in relation to the Herring Gull:

Overall there is far less black in the wingtip, appearing almost not much more than a slightly dipped in ink compared with the extensive black wedge on the Herring Gull.

- P10: Large white mirror with narrow subterminal band. The black behind the mirror is broad across both webs for about a quarter of the feather before the black then extends only along the outer web, narrowing towards the wing coverts. The appearance is of a pale grey tongue extending down along the feather.

- P9: rather large mirror which is clearly more larger on the inner web.

- P5: shows a distinct if narrow band.

WINTER BIRDS

SUMMER BIRDS

WINTER BIRDS

Click on the following links to select

Caspian Gull , adult, Undisclosed location, Essex 7th January 2012

A typical, probably male, large Caspian Gull.

Note the typical features of the species:

- Long slender, parallel edged and pale yellowish bill

- Dark looking eye set high and forward in the face

- Small head with low sloping forehead