A second calendar year 'michahellis' Yellow-legged Gull at Fishmoor Reservoir, Blackburn, Lancs, 18-19.09.02

by Bill Aspin.

Having no field experience of 1st or 2nd calendar year Yellow-legged Gulls had been really annoying me for the last year or so!

As Autumn 2002 approached, I decided to concentrate on the Gull roost at Fishmoor Reservoir (SD697260), to see whether I could pick out any YLG's of these age groups, as well as any older birds that I would be able to ID with more 'personal-certainty'.

Between mid-July - mid-September,  the only YLG, I had been able to find was a 3rd summer bird in August, which was very nice (click here to view an image of that bird), but saw nothing amongst the large numbers of younger LBB Gulls and the much smaller numbers of  Herring Gulls present to arouse any suspicions towards YLG, until I clapped eyes on this bird on 18.09.02. 

Upon determining the age of the bird, what struck me was the advanced state of plumage in relation to the apparent age of the bird. The almost clean white-headed appearance (but with slight smudge around eye), with a rather striking, thick, mainly dark and blunt tipped bill, coupled with the extent of the grey feathers on the mantle/scapulars which were also visible in the median coverts. Further scrutiny of the video taken, revealed dark-centred tertials and a 'two-toned' greater covert bar, with the outer greater coverts being darker and more uniform than the inners.

The bird was also noticeably larger and bulkier than nearby LBB Gulls (no Herring Gulls were in the immediate vicinity of the bird), was long winged giving it an attenuated rear-end and longer-legged. The legs appeared flesh coloured. I didn't see the open wing.

After consulting available literature at home, and confident in my mind that I had identified and aged the bird correctly, I emailed the images to Cambridgeshire ID expert Dick Newell, in order for him to talk me through the Gull so that I gain a fuller understanding of the bird. His reply was as follows:

"I would have no problem calling your gull a 2nd calendar year (2CY) 'michahellis'. Everything seems to be right to me, including:
1) Bill-shape
2) Very white head with eye-shadow and white eye-lids
3) Hint of a neck-shawl
4) Big anchor-shapes on the median coverts
5) Long legs
6) Dark-centred tertials (doesn’t show well in all shots)
7) Classic big white tail with tail-band
8) Very long wings giving a noticeable rear attenuation
9) Boat-shaped body
 

All you are missing is the inner primaries contrasting with the outers with a little translucency on the inner few. This is almost certainly a 'michahellis' from the Mediterranean rather than Atlantic Iberia.
Individual Herring Gulls can show one or more of all these features and there are some argentatus that turn up that look remarkably michahellis-like, so beware! The combination of all these features makes your bird 100% kosher in my opinion."

Many thanks to Dick Newell for taking the time to view the images and comment on the bird.

Click here to access Dicks website which includes extensive images of Yellow-legged and other Gulls. The link takes you directly to the YL Gull section.

If anybody has any other comments on this bird, please email  Bill Aspin.

Click here to view the Fishmoor Reservoir site guide.