Heuglini or graellsii

[Boris Belchev]

My first difficulty this season please help with ID?

Shame that I cut the wing but with 600 mm is difficult to keep the object in the frame... :-)

Heuglini or graellsii in flight (11042013).jpg (223.53KiB)Viewed 6001 times

[Ruud Altenburg]

I'm afraid it may not be of much help in this case, but location and date usually are pretty helpful clues...

[Boris Belchev]

Date is under each photo, 11.04.2013 and location is Zabieliškio landfill, Kedainiai district, Lithuania.

[marsmuusse]

Hi Boris,
Over the last 2 decades, we gained much info on plumage identification of several gull taxa in Europe. Unfortunately, separation of adult heuglini and adult graellsii is not one of these plumages, and so far, we believe there is a complete overlap in phenotypic characteristics of the two. As Ruud mentioned, location and date may be helpful, however, Dutch graellsii (ringed birds) have been recorded in S Finland and there is no reason why we should expect they cannot reach the Baltic states. Still, unringed birds in this region are probably best labeled heuglini, as this taxon is far more abundant.
Now pale-backed intermedius and dark-backed fuscus seem to be breeding in mixed colonies in at least N Norway, another option becomes apparent: offsprings from mixed couples. Such offsprings may look like U0JD: http://www.israel.gull-research.org/fuscus2cy/u0jd.html (but I have to add I'm not saying this is a true mixed bird, it was ringed in Israel, and we just don't know exactly where it's from). U0JD was recorded again in Poland last week by Mariusz Dąbek. No doubt, U0JD is the most discussed and most photographed of anu gulls in Israel, starting a debate over its identity. First it seemed to be fuscus, than became heuglini (supported by Amir), than questioned again by me as I believe this is most probabl;y from N Norway. And we are still not sure...

Now it has been recorded in a north-west direction from israel; very interesting and maybe this relatively large, pale-backed bird can be found in a Scandinavian colony. If so, it will raise debate over the possibilty of identifing true heuglini birds in Israel, despite the immense difference in magnitude of occurance. U0JD can be considered an Israeli "resident", spending every winter from its first winter till now in Israel, normally arriving on the 7th December and staying usually till 1st April. In fact, it was last seen at Ashdod Israel on 1.4.13 (by Ehud Dovrat) and arrived in Poland in 9 days or less: Total of 2590 Km in 9 days which is 288 Km per day (night), direction 330.08 degrees.

2 attachments: Lesser black-backed gull RED U0JD on 10.04.2013 at Sulisławice rubbish dump, Poland (50°52'26,7''N, 16°29'59,2''E).

Amir Ben Dov
Yoav Perlman
Mariusz Dąbek
Mars Muusse

[Boris Belchev]

Thank you Mars, very helpful post, I had two birds today and both were Heuglini gulls today, I didn't have time to proceed some more pictures, but I had a L.f.graellsii with dark blue ring, but I guess is good to share it in my main post. Cheers,