December 27, 2016

"Gulling" the East

part three

text and photos by ABu

(links to part 1, part 2)

Right then, now to the gulls. We drove up to the small lake called Bulangijn Tsagaan Nuur (nuur = lake), a little northeast of Buir Nuur and when we arrived on 22 May, it became clear that I probably would not be able to catch as many gulls as intended. Thanks to the previous disappointment at the first (former) colony, I had not expected much. Despite this it came quite as shock to see that this colony which we had also found in 2014, when about 250 pairs were breeding on three small islands, was almost completely gone. This lake was nearly dry and two of the islands did not exist anymore because the water level had dropped so much. Although the remaining island was still occupied by Mongolian Gulls, the number of nests was small. It turned out that there were only 30 nests containing eggs. Many of the gulls on the island were non-adults, strongly indicating that the more experienced gulls had left already. But not completely so: one adult Mongolian Gull that bred on the island was already wing-tagged. It had been individually marked as an adult by my team and me in 2004 some 250 km to the north west, hence it was at least 16 years old and hence not a at the beginning of its life as a breeding gull.

Upon arrival, an upcoming thunderstorm gave us the priority to pitching tents and I decided to catch and check the gulls during the next days. I had a lot of time to do the latter as the thunderstorm developed into straight rain that lasted for the next two days, preventing me from any ringing. I spent most of the days inside my tent and watched the gulls from the distance. Every evening between 400 and 500 gulls, mostly immatures, gathered near the island. So I checked them with the aid of my scope and paid particular attention to those not going conform to my idea of a mongolicus. After the rain had weakened and I tried to take record shots of some of the suspicious gulls I had found. It was still rather dark and windy so the long range (!) shots I achieved are of an awful quality and of course, I could not document all of them.

Luckily a gull that had immediately caught my eyes on our first day at the lake was still around: it was an adult large white-headed gull but it was obviously darker than any of the accompanying Mongolian Gulls. Further, it was not in primary moult and also showed very bright lemon yellow legs. This combination ticked my virtual boxes for Heuglin’s Gull. With the aid of my scope I found that it showed some smaller black markings on its 4 outer primary coverts (in the flight picture this black area looks bigger than it actually was because of blurring) but this does not necessarily mean that it wasn’t adult.

In the bag!


Adult Heuglin’s Gull (composite image)
Eastern Mongolia, May 2016, © Andreas Buchheim


Adult Heuglin’s Gull between mostly adult Mongolian Gulls
Eastern Mongolia, May 2016, © Andreas Buchheim


Adult Heuglin’s Gull between mostly immature Mongolian Gulls
Eastern Mongolia, May 2016, © Andreas Buchheim

There were other gulls which did not moult. They not only differed in this from the Mongolian Gulls of the same age. The odd birds fell into two groups: most of them (4 birds) showed rather white heads with a neck stola and many new feathers on the mantle and wing, giving them a rather fresh look. One bird of these four I considered to belong to heuglini not only because it was as dark (only adult like feathers compared, of course) as the adult (seen side by side once). It also showed a bright orangey pinkish bill with a black tip (like the bill of a young Glaucous Gull). Unfortunately I could not take any pictures of it. The others must have come from the breeding grounds along the arctic as well. For the summer time we are still beginning to get ideas about the ID of immature of those taxa breeding along the coasts of the Asian part of the Arctic Ocean (heuglini, taimyrensis, birulai and vegae; listened by the location of their respective breeding ranges from west to east) so I am not sure about their ID. It would be easiest to call all of them heuglini but probably much more honest to leave them unidentified.


Presumed 2cy Heuglin’s Gull landing behind Mongolian Gulls
Eastern Mongolia, May 2016, © Andreas Buchheim


Possible 2cy Heuglin’s Gull (different bird) between Mong.Gulls
Eastern Mongolia, May 2016, © Andreas Buchheim

The other “group” consisted actually of only a single individual. This one showed an almost evenly streaked head and its belly was also streaked just like those Herring Gulls I know from Europe. All newly replaced feathers of its mantle and wings weren’t plain just as I would expect from a vegae. Of this bird I also could not take any pictures so my observation cannot be recognized as a proper record (due to the previously mentioned uncertainties and no proof).

Gulls of these two kinds can be found in almost any larger gathering of immature gulls during spring and summer here and many of them have previously been attributed to heuglini. Based on our current non-knowledge on the variation of immature plumages of the aforementioned taxa (plus barabensis) only the most typical (what is typical in large white-headed gulls?), if any, might be identifiable.

For many years to come all future observers of such gulls are kindly requested to fully document them by means of photographs (preferably showing the bird also in flight from above and below), or ideally, DNA-sampling, as individuals which just have been photographed we might never be able to safely assign the documented gull to one of the taxa in question.

A Relict Gull entertained me and some Kentish Plovers for quite a while although the little plovers didn’t like that as much as I did. After the rain had stopped I could start ringing. In the end I caught 15 gulls which all got their set of wing-tags. Please watch out for them!


Mongolian Gull
Eastern Mongolia, May 2016, © Andreas Buchheim


Relict Gull
Eastern Mongolia, May 2016, © Andreas Buchheim


Relict Gull
Eastern Mongolia, May 2016, © Andreas Buchheim


Relict Gull and Kentish Plovers
Eastern Mongolia, May 2016, © Andreas Buchheim


Relict Gull and Kentish Plovers
Eastern Mongolia, May 2016, © Andreas Buchheim


Relict Gull and Kentish Plover
Eastern Mongolia, May 2016, © Andreas Buchheim

Relict Gull in flight
Eastern Mongolia, May 2016, © Andreas Buchheim

Because I got tired to sit and sit inside my tent I walked around each day just during the very few rain breaks, but mostly without my camera. Although migration was slow I found some more or less noteworthy birds:

On 23 May:
A flyby Eurasian Whimbrel (unclear which subspecies), c. 120 Spotted Redshanks, c. 300 Red-necked Stints, 9 Sanderlings, some of them sporting their sometimes very bright red breeding plumage.

On 24 May:
A nice flock of 6 taivana Yellow Wagtails (Green-crowned/Green-headed Yellow Wagtail), 3 Little Curlews, an Eurasian Bittern and 4 Caspian Terns.

On 25 May:
A male Amur Falcon dashing through the air towards the east, a dark morph Booted Eagle.

Then, on 26 May, we went on to the famous Khalkhgol plantation a little further up the river and shortly before we arrived a group of 7 Siberian Cranes was seen feeding on the banks of the Khalkh river. Here, many waders were busily foraging: among others I saw c. 1,600 Red-necked Stints, 13 Asian Dowitchers and 65 Curlew Sandpipers.

More about the birds that I saw in the plantation will be reported next!


2cy male Mongolian Reed Bunting
("ssp" lydiae of Pallas's Reed Bunting)
Eastern Mongolia, May 2016, © Andreas Buchheim


2cy male Mongolian Reed Bunting
("ssp" lydiae of Pallas's Reed Bunting)
Eastern Mongolia, May 2016, © Andreas Buchheim


Last light Pied Avocet
Eastern Mongolia, May 2016, © Andreas Buchheim


“tripod” Pied Avocet
Eastern Mongolia, May 2016, © Andreas Buchheim


4 of the 7 Siberian Cranes
Eastern Mongolia, May 2016, © Andreas Buchheim

December 23, 2016

“Gulling” the East

text and photos by ABu

part two

(link to part 1)

Right from the beginning of my visits to Mongolia, ringing (banding) gulls, especially Mongolian Gulls, has been my prime motive and this year’s first expedition was meant to be entirely devoted to wing-tag adult Mongolian Gulls. I had chosen to visit two colonies in the east of the country. Both colonies had been found during the famous “Swamprunner Tour 2014”.

We started on 20 May and hoped to reach to first colony by evening the same day. For several reasons, among them heavy traffic between UB and Nalaikh (the next bigger city to the east), we did not make it that far and camped on the banks of the Kherlen River a little east of the town formerly called Öndörkhaan, which has been renamed “Chinggis City” recently. It was very windy and we had only 15°C (59°F). During the fading light I walked around the camp and photographed some of the few birds around. A late Hen Harrier was noteworthy but bird of the day was doubtlessly a 2cy male Siberian Thrush. Unfortunately it was quite elusive and I could not even take a record shot. Teaser 1 of the first part was photographed on this evening and another photograph of this 2cy male Taiga Flycatcher can be seen below. Before we left after a cold (-2°C/28.4°F) and windy night I digitally got some more Taiga Flycatchers.

2cy male Taiga Flycatcher (teaser 1)
Eastern Mongolia, May 2016, © Andreas Buchheim


Adult male Taiga Flycatcher
Eastern Mongolia, May 2016, © Andreas Buchheim


Female Taiga Flycatcher
Eastern Mongolia, May 2016, © Andreas Buchheim


Portrait of the same female Taiga Flycatcher
Eastern Mongolia, May 2016, © Andreas Buchheim

Female Taiga Flycatcher
Eastern Mongolia, May 2016, © Andreas Buchheim

Then we went on to the colony, but when we arrived we had to learn that planning ahead is rather difficult in this country: The lake was dry and no gulls around (180 breeding pairs two years ago). This led us to press on and we reached our regular camp ground near Choibalsan by the afternoon of 21 May. As it was impossible to set up mist nets, thanks to the strong winds (this spring was extremely windy and cold, even for Mongolian standards!), I went for birding. Under these windy conditions it is not easy to find birds within the bushes that grow along the river. Every twig, every leaf is moving and catching an unusual movement (which ideally should be a bird, but sometimes is just a falling leaf or a butterfly) was a real challenge. Just before it got dark I found a male Mugimaki Flycatcher which posed for the teaser picture number 2. All the pictures I took that day were more or less blurred and I hoped that the bird would give me another chance the next day. Birds don’t move during unfavorable conditions like strong headwinds and if they have problems to feed (not many insects available when it is cold). So luckily the bird still was around the next day (22 May). The thick cloud cover didn’t help in photographing it well but at least I got some half decent shots. It was mostly feeding out in the steppe and not within the bushes which helped to keep track on it.

Male Mugimaki Flycatcher (teaser 2)
Eastern Mongolia, May 2016, © Andreas Buchheim

Male Mugimaki Flycatcher (teaser 2)
Eastern Mongolia, May 2016, © Andreas Buchheim

Male Mugimaki Flycatcher (teaser 2)
Eastern Mongolia, May 2016, © Andreas Buchheim

A pair of “Stoliczka’s” White-crowned Penduline Tits was busily building their nest. I only could take some picture of the male which still did not show the dark band across its nape. Only if seen from behind this area looked dark (see lowermost penduline tit picture). The pale tips to these feathers have to wear off so early in spring almost no male shows this dark band. Other birds along the river were 3 Eastern Spotbills and several Siberian Blue Robins. Generally there were not many birds around (or they were too good in hiding).

The water level of the river was about 1 m below what I think could be the average and it was quite murky, so we went into the city to bunker drinking water. There I saw more Siberian Blue Robins and two adult Siberian Thrushes in the (inaccessible so no pictures) gardens.

Male White-crowned Penduline Tit
Eastern Mongolia, May 2016, © Andreas Buchheim

Male White-crowned Penduline Tit
Eastern Mongolia, May 2016, © Andreas Buchheim

Male White-crowned Penduline Tit
Eastern Mongolia, May 2016, © Andreas Buchheim

2cy male Daurian Redstart
Eastern Mongolia, May 2016, © Andreas Buchheim

2cy male Siberian Blue Robin
Eastern Mongolia, May 2016, © Andreas Buchheim

The same Siberian Blue Robin from behind
Eastern Mongolia, May 2016, © Andreas Buchheim

Pair of Eastern Spotbills
Eastern Mongolia, May 2016, © Andreas Buchheim

We then went on toward Buir Nuur and arrived at the second of the chosen gull colonies in the late afternoon after a rather eventless journey through the steppes of Menengijn Tal. Only hundreds of larks and very few migrants like Isabelline Shrikes and an Eastern Buzzard were around. A colony of Pied Avocet consisted of c100 pairs. Three Whimbrels flew over so I could not identify the subspecies they belonged to. And then… more next so come back!

Pied Avocett colony
Eastern Mongolia, Mai 2016, © Andreas Buchheim