Literature type: Scientific
Journal: Wildfowl
Volume: SpecIs 6 , Pages: 206–243.
Language: English
Download:Full reference: Ao, P., Wang, X., Solovyeva, D., Meng, F., Ikeuchi, T., Shimada, T., Park, J., Gao, D., Liu, G., Hu, B., Natsagdorj, T., Zheng, B., Vartanyan, S., Davaasuren, B., Zhang, J., Cao, L. & Fox, A. 2021. Rapid decline of the geographically restricted and globally threatened Eastern Palearctic Lesser White-fronted Goose Anser erythropus. Wildfowl SpecIs 6: 206–243.
Keywords: abundance, key sites, migration routes, population trends, telemetry tracking, China, Asia
Abstract:
The Lesser White-fronted Goose Anser erythropus, which breeds across northern Eurasia from Norway to Chukotka, is globally threatened and is currently classified as Vulnerable by the International Union for Conservation of Nature. The Eastern Palearctic population of the species was thought to breed in arctic Russia, from east of the Taimyr Peninsula to Chukotka, and to winter in East Asia, but its precise status, abundance, breeding and wintering ranges, and migration routes were largely unknown, reducing the effectiveness of conservation efforts. In this paper, we combined results from satellite tracking, field surveys, a literature review and expert knowledge, to present an updated overview of the winter distribution and abundance of Lesser White-fronted Geese in the Eastern Palearctic, highlighting their migration corridors, habitat use and the conservation status of the key sites used throughout the annual cycle. Improved count coverage puts the Eastern Palearctic Lesser White-fronted Geese population at c. 6,800 birds in 2020, which represents a rapid and worrying decline since the estimate of 16,000 in 2015, as it suggests at least a halving of numbers in just five years. East Dongting Lake (Hunan Province) in China is the most important wintering site for the species in East Asia, followed by Poyang Lake (Jiangxi Province) and Caizi Lake (Anhui Province), with one key wintering site in Miyagi County in Japan. Satellite tracking showed that eight individuals captured during summer on the Rauchua River, Chukotka, Russia wintered in the middle and lower reaches of the Yangtze River floodplain in China. Their migration speed was slower in spring than in autumn, mainly because of longer stopover duration at staging sites in spring. The tracked geese mainly used cultivated land on migration stopovers (52% in spring; 45% in autumn), tundra habitat in summer (63%), and wetlands (66%) in winter. Overall, 87% of the GPS fixes were in protected areas during the winter, far greater than in spring (37%), autumn (28%) and summer (7%). We urge more tracking of birds of differing wintering and breeding provenance to provide a fuller understanding of the migration routes, staging sites and breeding areas used by the geese, including for the birds wintering in Japan. The most urgent requirement is to enhance effective conservation and long-term monitoring of Lesser White-fronted Geese across sites within China, and particularly to improve our understanding of the management actions needed to maintain the species. Collaboration between East Asian countries also is essential, to coordinate monitoring and to formulate effective protection measures for safeguarding this population in the future.
Literature type: Scientific
Journal: Wildfowl
Volume: 68 , Pages: 44-69.
Language: English
Download:Full reference: Cuthbert, R.J., Aarvak, T., Boros, E., Eskelin, T., Fedorenko, V., Karvonen, R., Kovalenko, A., Lehikoinen, S., Petkov, N., Szilágy, A., Tar, J., Timonen, S., Timoshenko, A., Zhadan, K. & Zuban, I. 2018. Estimating the autumn staging abundance of migratory goose species in northern Kazakhstan. Wildfowl 68: 44-69.
Keywords: Anser erythropus, Branta ruficollis, flyway population estimates, sampling methodology.
Abstract:
Northern Kazakhstan and adjoining areas of Russia have vitally important autumn staging sites for arctic breeding geese, especially for the globally threatened Lesser White-fronted Goose Anser erythropus (LWfG) and Red-breasted Goose Branta ruficollis (RbG). Part of the Fennoscandian and the entire Western Main subpopulations of LWfG and the global population of RbGs are believed to stage there, which facilitates obtaining up-to-date population estimates for these species. A total of 80 lakes were surveyed across four survey areas in autumn 2016, recording more than 1.2 million geese in the region. Greater White-fronted Geese Anser albifrons (GWfG) were the most abundant with an estimated c. 890,000 birds, with counts of c. 250,000 Greylag Geese Anser anser, c. 53,000 Ruddy Shelduck Tadorna ferruginea, c. 39,100 RbG and c. 32,000 LWfG also recorded during the surveys. Based on a priori lake classification for both LWfG and RbG, to stratify survey lakes in order to generate total population estimates, survey teams visited a sample of different lake types. After removing lakes smaller than the observed minimum lake size used by each species, the total number of potential lakes available within the core staging areas of each species (335 lakes of > 320 ha for LWfG; 361 lakes of > 100 ha for RbG) was calculated. Bootstrapping procedures, with replacement, were then used to estimate the total numbers likely to be present in the region. These calculations produced total estimates of 34,250 birds (95% confidence intervals = 28,500–40,100 birds) for the Western Main population of LWfG (well in excess of current population estimates of 8,000–13,000 individuals) and an estimated population of 50,100 RbG (95% CI = 28,100–72,600 birds), broadly similar to recent population estimates of 55,000–57,000. We recommend that future surveys continue to monitor as large a region and as many lakes as possible in order to capture inter-annual variation in the distribution of birds and to provide more reliable assessments of population size and trends of these migratory species.
Literature type: Scientific
Journal: Bird Conservation International
Volume: 22 , Pages: 128-134.
DOI: 10.1017/S095927091100030X
Language: English
Full reference: Wang, W., Fox, A.D., Cong, P., Barter, M. & Cao, L. 2012. Changes in the distribution and abundance of wintering Lesser White-fronted Geese Anser erythropus in eastern China. Bird Conservation International 22: 128-134. https://www.dx.doi.org/10.1017/S095927091100030X
Abstract:
The Lesser White-fronted Goose Anser erythropus is globally threatened with an estimated world population of 25,000 28,000, of which c 20,000 winter at East Dongting Lake, China. We present here the first collation of published and unpublished data on the distribution and abundance of the species in eastern China in recent decades. Lesser White-fronted Goose numbers have declined greatly in Anhui, Jiangxi and Jiangsu Provinces between the late-1980s/early-1990s and recent years: the species’ range has now mainly contracted to East Dongting Lake in Hunan. The relatively stable numbers at East Dongting Lake suggest that the population is not currently threatened, but the extreme concentration at one lake makes the species vulnerable. Lesser White-fronted Geese rely on very specific meadow vegetation exposed after water recession, so changes in water levels or recession timing, due to hydrological changes following the commissioning of the Three Gorges Dam, may affect biomass, palatability and plant species composition of the meadows. Thus, it is critically important to understand the wintering ecology and habitat needs of this threatened species at East Dongting Lake. It is also essential to conduct further synchronous Yangtze River floodplain surveys to assess the current status, distribution and habitat use of Lesser White-fronted Geese throughout the region.
Number of results: 3