BIRDING MONGOLIA

Finding flava

text by BirdingMongolia

Not only since the ground-breaking publication on the taxonomy of the Horned Lark aka Shore Lark, which had been published online in January 2014 (Drovetski et al.: Limited phylogeographic signal in sex-linked and autosomal loci despite geographically, ecologically, and phenotypically concordant structure of mtDNA variation in the Holarctic avian genus Eremophila; full article online available here), BirdingMongolia has been treating the two taxa occurring in Mongolia separately. Drovetski and colleagues suggest splitting Horned Lark Eremophila alpestris (sensu lato) into no less than six species:

E. alpestris (sensu stricto) - North America (and an isolated population in Colombia in South America), further study needed within this group
E. elwesi - southern and eastern Tibetan Plateau
E. atlas - western North Africa (Atlas Mts, Morocco)
E. penicillata - Balkans to northern India
E. brandti - SE European Russia (lower Volga) and N Transcaspia E to Mongolia, occasionally wintering as far south as South Korea. It has been considered a ‘scarce passage migrant and winter visitor’ in Beijing (nearly all of Beijing's records of Horned Lark, when identified to subspecies, have been brandti). Up until the start of autumn 2014 there were perhaps no more than 21 reports of Horned Larks in Beijing (all between 7 October and 22 March). However, on 15 October 2014, Paul Holt counted a staggering 8,824 migrating south at Miyun Reservoir, not just a record count for Beijing but also for China (T. Townsend pers. comm.)
E. flava - breeding across in the Palaearctic tundra from N Scandinavia to NE Russian Far East, entirely migratory, wintering at the coasts of the southern North Sea and western Baltic, in fluctuating numbers inland in north-central and eastern Europe, and in large numbers across southern former Soviet Union, e.g. reaching Sea of Azov, northern Caucasus, Kazakhstan steppes, and further east, wintering in low [?] numbers in Mongolia. Only once recorded from Beijing (T. Townsend pers. comm.)

For the two taxa that have been recorded in Mongolia several English names have been suggested:

E. brandti
Steppe Horned Lark (used, for example, by Birds of Kazakstan and www.birds.kz), Mongolian Horned Lark (in use by BirdingMongolia), or Brandt’s Lark

E. flava
Traditionally, this taxon has been called Shore Lark, an appropriate name, since it is he only taxon within the complex that occurs almost exclusively on the coast in winter, i.e. at the “shore”. Birds of Kazakhstan, for example, uses “Shore Lark” for flava already. Other names that have been put forward are Common Horned Lark (www.birds.kz), Arctic Horned Lark or Northern Horned Lark.

Brandti is arguably the most numerous bird of Mongolia and this might be one of the reasons why we don't have many records of the second taxon recorded in the country: flava. Nobody likes to look that much at common species. Another reason certainly will be the fact that there are not many people out in the field when flava (presumably) can be seen. Nobody likes to go out birding when it is bitterly cold.

Winter flock of Mongolian Horned Lark E. brandti.

Can you spot them (at minus 30°C/minus 22°F)?

Buyant river valley, Khovd. © Axel Bräunlich

It also might be that flava is actually not a common winter guest in Mongolia. However, in neighbouring Kazakhstan, flava is a regarded as common winter visitor (from late September to April), occurring throughout the plains. It occurs occasional in the southern Altai.

wintering Shore Larks Eremophila flava

Kostanay Oblast, northern Kazakhstan, Nov 2011

During his permanent stay in Khovd, at the foot of the Mongolian Altai in western Mongolia from October 2005 to December 2007, Axel noted in his 23 sqkm-study area, a stretch along the lower Buyant gol (river) valley in Jargalant sum, immediately adjacent to Khovd city, a total of 3208 bird-days of Mongolian Horned Lark (and thousands just outside the study area), but only once he saw Shore Larks: Three among brandti on 8 March 2006.

With this post we would like to encourage birders to seek for flava whenever they have the chance to do so. Still, we don't have any good field picture from Mongolia of flava and the number of sight records remains below 10!

To illustrate how brandti looks like at the moment, we have included some recent pictures. Note that there is almost no yellow in the face of brandti and also note the variation in the prominence of streaks on their back. Further they do not show large brownish patches on the breast sides. Also included is a number of shots taken with permission of the Mongolian Academy of Sciences (MAS). The flava had been collected in western Mongolia. Compare the overall differences in coloration and size of the breast side patches. Many flava exhibit even a complete brownish breast band below the black.

Shore Lark E. flava (top)

Mongolian Horned Lark E. brandti (bottom)

skins at Mongolian Academy of Sciences, Jan 2015

photo © A. Buchheim

Shore Lark E. flava (top)

Mongolian Horned Lark E. brandti (bottom)

skins at Mongolian Academy of Sciences, Jan 2015

photo © A. Buchheim

Shore Lark E. flava (left)

Mongolian Horned Lark E. brandti (right)

skins at Mongolian Academy of Sciences, Jan 2015

photo © A. Buchheim

Mongolian Horned Lark E. brandti

Ulaanbaatar, Jan 2015, photo © A. Buchheim

Mongolian Horned Lark E. brandti

Ulaanbaatar, Jan 2015, photo © A. Buchheim

Mongolian Horned Lark E. brandti

Ulaanbaatar, Jan 2015, photo © A. Buchheim

Mongolian Horned Lark E. brandti

Finally, it should be noted that another taxon of the Horned Lark-complex, the Pamir Horned Lark (as called by www.birds.kz) or Caucasian Horned Lark (as in Birds of Kazakhstan), with the subspecies albigula breeding as close to Mongolia as the Tien Shan Mountains, could possibly occur in the country, too, most likely in the south-west. In this taxon, the black colour of the cheeks and the breast merges, forming a black ring around the white throat.

Pamir Horned Lark E. penicillata albigula

Zailiyskiy Alatau, N Tien Shan Mts, Kazakhstan, Jun 2012

BirdingMongolia would like to thank Dr. N. Tseveenmyadag for granting access to the collection of the MAS and for the excellent collaboration our thanks go to WSCC as well! Further thanks go to Vassiliy Fedorenko and Aleksey Timoshenko for allowing us to use their photos (from www.birds.kz). Terry Townsend/Birding Beijing kindly provided details on the status of Eremophila in Beijing.

BIRDING MONGOLIA

February 22, 2015

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