The breeding range of the Western main population of the Lesser White-fronted Goose is now heavily fragmented, with discrete breeding areas restricted within European Russia to the Malozemelskaya tundra, Bolshezemelskaya tundra and the Polar Urals. In Asian Russia, the remaining breeding areas are located at the Yamal Peninsula, Taimyr Peninsula and the Putorana Plateau (Morozov & Syroechkovski Jr. 2005). Surveys carried out in tundra and forest tundra habitats since the 1990s all reveal reductions in breeding ranges.
The lack of extensive surveys and identification difficulties, especially associated with distinguishing this species from the very similar White-fronted Goose, has hampered the compilation of knowledge about the wintering distribution and numbers of this population. However, present day estimates of numbers during winter represent only 20-25% of the numbers of Lesser White-fronted Geese estimated during autumn staging in Kazakhstan. Currently, our best available information suggests that the main wintering quarters of Lesser White-fronted Geese from this population are mainly located in Azerbaijan, Iran and adjacent territories. Estimates from the 1990s to the present put the wintering population in Azerbaijan at 1,500-7,000 individuals (Patrikeev 2004), although recent satellite tracking results show that the Aras dam at the border of Nakhichevan (an autonomous exclave of Azerbaijan bordering Armenia and Turkey) and Iran to be of particular importance (Lampila & Eskelin 2015). These areas were unknown until recently (own unpublished data, Morozov et al. 2014, 2015, 2016) and due to their present inaccessibility, have yet to be properly surveyed, but initial work has located 2,500-3,000 birds here (www.piskulka.net, Lampila & Eskelin 2015, unpublished data). Satellite tracking has also shown that the area of Mesopotamia within the territory of Iraq is of importance, but war makes surveying the identified areas extremely dangerous and difficulty to access (cf. Morozov & Aarvak 2004). In addition to these areas, wintering Lesser White-fronted Geese are also known to occur in Iran within the Gorgan Gulf, at the hypersaline Lake Urmia (in Eastern and Western Azerbaijan Provinces), and (formerly) in the Fars and Husestan provinces. Except for those wintering in the Aras river valley, the numbers elsewhere are probably low. However, out of 32 satellite tagged Lesser White-fronted Goose tracked from the breeding areas in Northwest Russia, only one bird failed to cross over to the west side of the Caspian Sea. This individual instead flew southwards on the eastern side to ultimately winter in the border areas between Uzbekistan and Turkmenistan, suggesting that these areas might also be of considerable importance for wintering Lesser White-fronted Geese (Morozov et al. 2016). Lack of detailed surveys makes this area virtually unknown, but according to Kreuzberg-Mukina (2003) the species occurred on migration and in winter locally within the water reservoirs of the basins of Amu-Darya and Syr-Darya rivers, southern Aral region, the Dengizkul, Aydarkul lakes, and the Chardara and Surkhandarya water reservoirs. The species uses the floodlands of rivers, large reservoirs with well-developed submerged and bank vegetation and cereal fields. In the past, the species was observed in extremely low numbers, but during early 2000s, from 200 to 2000 individuals have been reported annually during migration and in winter (Kreuzberg-Mukina 2003, Morozov & Syroechkovski Jr. 2005). Observations of pairs and single Lesser White-fronted Geese (which add up to hundreds of birds) in Eastern and Western Europe, from Romania, Bulgaria to Hungary, Germany and the Netherlands, are likely to be birds following the larger western flyways of White-fronted Geese Anser albifrons (see section A1) to their wintering areas.
Flyway population estimate
Due to the remote and scattered nature of the breeding grounds, and similarly due to limited access to key wintering areas, total population estimates for several goose species wintering in central and south-western Asia are based, of necessity, on counts undertaken during autumn migration. This is the case for five goose species which utilize staging areas in northwestern regions of Kazakhstan and bordering areas of Russia on route to their more southerly wintering grounds. These areas are of key significance for the Lesser White-fronted Goose as parts of the Fennoscandian population (annual average of 50%, c.100-150 birds; Fox et al. 2010, Aarvak & Øien in prep.) and the entire Russian Western Main subpopulation stage there for a period of 3-5 weeks. Surveys undertaken in these regions during the 1990s (Aarvak et al. 2004, Gurtovaya et al. 1999, Tolvanen & Pynnönen 1997, Markkola et al.1997, Tolvanen et al. 1999a, 2000, 2001, Yerokhov et al. 2000, 2004) suggested a population estimate of roughly 10,000-21,000 during autumn migration (Fox et al. 2010). During the last ten years, a variable number of lakes (13-80) have been surveyed annually, where the Kostanay region in Kazakhstan has been covered every year. Within this region, the number of LWfG has varied between 2,000-31,000 individuals. However, the counts carried out at this time of year continue to have problems associated with coverage and turnover, which has restricted our ability to generate reliable population estimates from these surveys. Among the counts from Kostanay, the annual number of lakes surveyed explains 23% of the variation in total numbers. However, data from simultaneous counts from more staging sites on the Russian side of the border (Orenburg oblast) and Akmola region with larger teams of observers during last 5 years suggested a population between 17,500 and 30,800 birds (Rozenfeld 2011, Rozenfeld et al. 2012; Rozenfeld et al. in print). In 2016, a large scale coordinated survey was organized covering Kostanay, Akmola and Northwestern Kazakhstan and two important lakes in Orenburg Oblast in Russia, totaling 80 visited lakes. Extrapolating the results, taking into account the number of suitable, but unsurveyed lakes within the core staging areas of the species, produced an estimated total of 34,250 birds present, comprised of around 23,600 adults and 10,650 juveniles based on the age ratio observed in 2016 (Cuthbert & Aarvak 2017).
Long term high quality count data from the Western main population is lacking, but annual counts in Kazakhstan during autumn suggest the population to be stable. The survey results during the last 10 years are 2-3 times higher than in the 1990s, but it is difficult to determine whether this represents a genuine increase in Lesser White-fronted Goose abundance, or more reflects incomplete survey in previous years. What is clear is that numbers of Lesser White-fronted Geese can vary greatly from year to year. For instance, numbers recorded at the Taldykol/Kulykol lake system, the most important staging site in this region, were 1,552, 207 and 5,400 birds in 2008, 2009 and 2010, respectively, compared with records of 19,566, 2,239 and 23,205 in 2014, 2015 and 2016 (Rozenfeld 2011, Rozenfeld et al. 2012; Rozenfeld et al. in print, Cuthbert & Aarvak 2017). The variation in these six estimates is too extreme to exclusively reflect natural variation in the overall size of the actual population, and is more likely to result from annual variation in the distribution of birds across the landscape.
Aarvak, T., Arkiomaa, A., Tolvanen, P. & Øien, I.J. 2004. Inventories and catching attempts of Lesser White-fronted Geese at Lake Kulykol, Kazakstan, in 2002 and 2003. Pages 36-40 in Tolvanen, T., Aarvak, T., Øien, I.J. & Timonen, S. (eds.). Fennoscandian Lesser White-fronted Goose conservation project. Report 2001-2003. WWF Finland Report No 20 & Norwegian Ornithological Society, NOF Rapportserie Report No 1-2004. Gurtovaya, E., Tolvanen, P., Eskelin, T., Øien, I.J., Bragina, T., Aarvak, T., Eichhorn, G., Arkiomaa, A., & Timonen, S. 1999. Preliminary results of the Lesser White-fronted Goose monitoring in Kazakhstan in October 1999. Casarca 5: 145-154 (In Russian with English summary). Cuthbert, R. & Aarvak, T. (Compilers) 2017. Population estimates and survey methods for migratory goose species in Northern Kazakhstan. AEWA Lesser White-fronted Goose International Working Group Report Series No. 5. Bonn, Germany. Kreuzberg-Mukhina, E. 2003. Lesser White-fronted Goose. The Red Data Book of the Republic of Uzbekistan. Vol. II, Animals. “Chinor-ENK”, Tashkent. . Lampila, P. & Eskelin, T. 2015. Monitoring of Lesser White-fronted Geese Anser erythropus in Northern Iran. AEWA Lesser White-fronted Goose International Working Group Report Series No. 4. Bonn, Germany. Markkola, J., Pynnönen, P., Tolvanen, P., Veersalu, A. & Yerohov, S. 1997. The second international Lesser White-fronted Goose Anser erythropus expedition in NW Kazakstan in May 1997. Pages 21-22 in Tolvanen, P., Ruokolainen, K., Markkola, J. & Karvonen, R. (eds). Finnish Lesser White-fronted Goose conservation project. Annual report 1997. WWF Finland Report No 9. Morozov, V.V., Øien, I.J. & Aarvak, T. 2016. Monitoring and satellite tracking of Lesser White-fronted Geese from the Russian European tundra in Russia in 2015. NOF-BirdLife Norway - Report 2-2016. Rozenfeld, S., 2011. The numbers of Red-Breasted Goose (Branta ruficollis) and Lesser White-fronted Goose (Anser erythropus) on the migration routes in 2010. Goose Specialist Group Bulletin 12: 8–14. Rosenfeld, S.B., Timoshenko, A.Y. & Vilkov, V.S. 2012. The results of goose counts on the North-Kazakhstan stopover site in autumn 2012. Casarca 15: 115–124 (in Russian, with English summary). Rosenfeld, S.B., Timoshenko, A.Y. & Zuban, I.A. In press. Monitoring of populations of geese and geese north-Kazakh migration stopover as a basis for conservation measures. Branta 19 (in press). Tolvanen, P., Aarvak, T. & Bragina, T. 2001. Conservation work for wetlands and monitoring the autumn staging of Lesser White-fronted Goose in the Kustanay region, north-west Kazakhstan, in 2000. Pages 30-33 in Tolvanen, P., Øien, I.J. & Ruokolainen, K. (eds.). Fennoscandian Lesser White-fronted Goose conservation project. Annual report 2000. WWF Finland Report 13 & Norwegian Ornithological Society, NOF Rapportserie Report No 1-2001. Tolvanen, P., Eskelin, T., Aarvak, T., Eichhorn, G., Øien, I.J. & Gurtovaya, E. 2000. Monitoring the autumn staging of Lesser White-fronted Geese in Kazakhstan, October 1999. Pages 43-50 in Tolvanen, P., Øien, I.J. & Ruokolainen, K. (eds.). Fennoscandian Lesser White-fronted Goose conservation project. Annual report 1999. WWF Finland Report 12 & Norwegian Ornithological Society, NOF rapportserie Report No 1-2000. Tolvanen, P., Litvin, K.E. & Lampila, P. 1999a. Monitoring the autumn staging of Lesser Whitefronted Geese in north-western Kazakhstan, October 1998. Pages 42-46 in Tolvanen, P., Øien, I.J. & Ruokolainen, K. (eds.). Fennoscandian Lesser White-fronted Goose conservation project. Annual report 1998. WWF Finland Report 10 & Norwegian Ornithological Society, NOF rapportserie Report No 1-1999. Tolvanen, P. & Pynnönen, P. 1997. Monitoring the autumn migration of Lesser White-fronted Goose Anser erythropus and other geese in NW Kazakhstan in October 1996. Pages 19-20 in Tolvanen, P., Ruokolainen, K., Markkola, J. & Karvonen, R. (eds). Finnish Lesser Whitefronted Goose conservation project. Annual report 1997. WWF Finland Report No 9. Yerokhov, S.N., Beryozovikov, N.N., Kellomäki, E.N. & Ripatti, N.L. 2000. Lesser White-fronted and other goose species in Kazakhstan during migration. Casarca 6: 121-159 (In Russian with English summary) Yerokhov, S.N., Kellomaki, E.N., Beryozovikov, N.N. & Ripatti, N.L. 2004. Autumn numbers and distribution of lesser white-fronted geese and other goose species in the Kostanay oblast, Kazakhstan, in 2002-2004. Casarca 10: 163-167 (In Russian with English summary)
The text about the western main population is from the unpublished report: A GLOBAL AUDIT OF THE STATUS AND TRENDS OF ARCTIC AND NORTHERN HEMISPHERE GOOSE POPULATIONS - by Anthony D. Fox & James O. Leafloor. The chapter about the western main popualtion is written by Tomas Aarvak & Ingar Jostein Øien, NOF - BirdLife Norway, and Vladimir Morozov, All-Russian Research Institute for Nature Conservation, Russian Federation.