18 Mar 2016

First calendar year gull – Sabkhat Al Fasl

Whilst birding at Sabkhat Al Fasl at the end of November I found a first calendar year gull sitting on the edge of a flooded lake. It is unusual in Saudi Arabia to get close to large white-headed gulls so this was a pleasant surprise. It is possible the bird was injured in some way as it was under some overhead power lines but there was no obvious signs of any injury. Anyway after taking a number of photos I left it in the same place as I found it hoping it was all right. Another problem was identifying the bird as although it looked superficially like a Steppe Gull barabensis it also had feature of Caspian Gull cachinans although I thought the bill size and shape was wrong for that species (but see below). As I was uncertain of the identity I sent it to Jan Jorgensen and expert gull enthusiast and birder who is always willing to share this thoughts on identification with me. Jan gave me the following thoughts on the bird “As the photograph was taken in November it´s quite worn with many 2nd generation scapulars, which are a bit worn already, with a few juvenile rear ones. Seemingly there are no 2nd generation coverts and tertials. So could it be a Caspian Gull? Scapular pattern, tertial and to a certain degree, covert pattern, do fit a 1cy Caspian. The bill dimensions and shape of it would fit a male type bird. The alternative species would be Heuglin’s Gull heuglini or Steppe Gull barabensis. The bird looks better and favours Steppe Gull on wear, however, some heuglini are more advanced it seems, with many 2nd generation scapulars at this time of year, but probably less worn otherwise. Many barabensis also have many 2nd generation coverts in November. Separating many barabensis from heuglini is quite a challenge, as you would know. Coverts have much white admixed, not solidly darkish as usual in the mentioned three. So, I dare not to be so confident in identifying your gull, although there’s something of a heuglini/barabensis structure over it. Pity that there aren´t any more pictures”. As always I am very grateful to Jan for his help and advice on this tricky gull.

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