Baraba-type Gulls, Oman

[Hans Larsson]

Hi all,

I´ve uploaded some barabensis-type Gulls from northern Oman nov-dec 09:

http://www.pbase.com/hans_larsson/barab ... _&page=all


Any comments are most appreciated. I had quite a hard time to separate certain birds from heuglin´s/taymyrensis and also cachinnans.

Cheers

Hans

[marsmuusse]

Hi Hans,

Especially immature and juvenile birds can give head-aches in the Near East. A couple of years ago I spent a few weeks in Bahrain, and faced the same difficulties. First of all: just accept an incredible portion (in European context) of the birds are probably not safely ID-ed. Once accepted that, there are some helpfull clues:

JUVENILES
1. Birds in the Persian Gulf belong to either birds from the 'Tundra Belt' or from the 'Steppe Belt'. Tundra Belt breeders are heuglini / taimyrensis and fuscus. In comparison with the next group, these taxa are late breeders and the juveniles arrive with a plumage in much fresher condition in the Gulf. Often, these juveniles are still in complete juvenile plumage upon arrival, at most a few scapulars replaced by November. Juvenile feathers look relatively fresh.
Steppe Belt breeders which can be expected should be barabensis and cachinnans, and maybe an out of range michahellis / armenicus (but often these observations may in fact be barabensis as well?). The juveniles of this group fledge much earlier in the season, with -by September/October- replaced scapulars and wing coverts. By November the juvenile feathers are often somewhat bleached and worn. Also take a closer look at head feathers, neck and side of the breast. Steppe Belt juveniles often have moulted feathers in this area by November.

2CY / 3CY BIRDS
Moult schemes are probably easiest clues. 2cy Fuscus and heuglini have often irregularities in the moult scheme for secondaries and primaries. And they show growing feathers until late in winter (although the period you have visited the Gulf is rather soon after arrival of these birds and they may then have arrested moult to migrate).
However, as far as I know, barabensis and cachinnans normally follow a moult timing much more in line with e.g. michahellis. Also, when adult-like feathers are visible, grey tone should give indications.

IMMATURE / ADULTS
Upperpart grey tone should be the first clue to at least seperate fuscus and heuglini from the bulk of barabensis and of course the much paler cachinnans. The ID between cachinnans and barabensis is hard to make in quite some birds...

Mars

[JanJ]

Hello Hans!

First of all, a selection of very good and interesting picures!
Secondly, the approach outlined by Mars is probably the most sound one reagarding the identification problematics at the moment, probably for many years to come, if ever, if you suffer from pessimism
From a wear and moult point of view, many of Hans 1cy looks like barabensis, some of these are more advanced and perhaps some of the less advanced might be heuglini. Some looks like cachinnans: http://www.pbase.com/hans_larsson/image/120150384

Another set of Oman gulls from Oct & Nov.

http://www.pbase.com/dophoto/zafferanos ... o&page=all

Goa Nov.

http://picasaweb.google.com/mark.seawat ... GullsNov08#

[Hans Larsson]

Thank´s Mars & Jan for your comments! Yes, one definitely has to accept the fact that many must be left without labelling.. Also, it´s a bit easier when not observing a mass of ID-subjects at the same time, when spending most of the time photographing each individual rather than actually observing the birds. With limited time on a travel, this is always a dilemma, of course...

However, during calmer moments in the field, the heavier and, almost HEGU-like, bulky build of Heuglin´s compared to the more slender and delicate (thus close to cachinnans) of Steppe Gull was notable. Although, some small Heuglin´s may complicate matters, it worked well for most, and also correlated well with mantle shade, moult and head streaking. Among several of the paler juveniles, the flanks and breast sides were strikingly dotted rather than neatly barred, but I don´t know if this may be of any value compared to Steppe. Hopefully I can upload some Heuglin´s type birds later today.

Hans

[JanJ]

By the way Mars, what happend to that birdsnaps barabensis site you made some years ago, covering 2cy + 3cy and adults?

[marsmuusse]

By the way Mars, what happend to that birdsnaps barabensis site you made some years ago, covering 2cy + 3cy and adults?

Jan,
These images were put aside. Not included in the new ORG site. It was fun to be there, but we collected not enough data to do anything substantial with it. Also, we only ringed a few birds, instead the numbers we had in mind

Mars

[JanJ]

While on the barabensis-type track, this gull seen in Stockholm this year, and identified as a Caspian at first but later on thoughs of a possible barabensis influence was considered.

The first 6 pic. here:

http://www.pbase.com/zoothera/caspiangull

http://www.artportalen.se/birds/gallery ... eID=165336

http://www.netfugl.dk/pictures.php?id=s ... e_id=29295

Jan

[Ruud Altenburg]

With these mixed cachinnans/heuglini/? colonies in Russia, trying to ID birds like this will be a hell of a job!

[JanJ]

With these mixed cachinnans/heuglini/? colonies in Russia, trying to ID birds like this will be a hell of a job!

Looking over Hans pic, and many others who have contributed with pic. from the region, the darker heuglinis (current knowledge as we have come to know) compared to the paler barabensis and cachinnans or possibly other candidates (?) (current knowledge as we have come to know) stands out quite obvious with all the combined features compared to each other, very much as we would except from a western point of view regarding 'our own' species/ssp. Of course, LWHG are a challenge where ever they are encountered, may it be on our local patch, in the Middle East or E. Asia. Knowing the human race, it´s going to be an on going process which I would very much liket o be alive to see!
Yes, a lot of maybe, possible, probably, could be, indicating, showing characters of, impossible, hell of a jobb , and so on...acceptable by necessity through lack of knowledge!
It´s a challange, no doubt. Certainly more study on the breeding grounds are needeed. We know how they look (mostly) but not what to call them.
One (wellknown) birder I know, once said - "why the fuss over these gulls, there systematics and how they look, probably less problematic than you care to accept', just name them what you find best, that´s what you do anyway". Those are not necessarily my own thoughs, but occasionally...

Jan

[Ruud Altenburg]

Take a look a this then...
http://www.flickr.com/photos/neubauerg/ ... 508214870/