KOFFIJBERG K, HUSTINGS F , JONG A DE , HORNMAN M & WINDEN E VAN (2011) Recent developments in numbers and distribution of Taiga Bean Goose Anser fabalis in The Netherlands. LIMOSA 84 (3): 117-131.

The status and identification of Taiga Bean Goose have been subject of debate in the past decades all over Europe. Recent findings have shed more light on its taxonomic status and wintering distribution. In The Netherlands, the species traditionally occurred in larger numbers in cold winters like 1979/1980 and 1984/1985-1986/1987, as a result of influxes from the regular wintering sites in the Baltic (Figs. 1-2). However, a more recent increase in numbers since the mid-1990s, apparent in the monthly goose counts, contrasted with reports of a contraction of the wintering range and a decline in the total flyway population. In addition, identification pitfalls arose, partly because an increasing number of 'black-billed bean geese' were reported as fabalis too. This prompted us to investigate all fabalis records in the national goose count database from 1990/1991 onwards. All observers who had submitted counts of Taiga Bean Geese were requested to check and comment upon their records, given the new insights in status and identification. Only one third of these (33%, N = 2073) were confirmed to be Taiga Bean Geese. The remaining records were withdrawn or regarded as uncertain, as further documentation was not available. Flocks of more then 100 individuals were checked particularly carefully and were accepted only when convincing documentation existed. To complete the current assessment of status and distribution, all observations entered through the online platform www.waarneming.nl in the last two cold winters of 2009/2010 (434 records, including duplicates) and 2010/2011 (607 records), were checked on the basis of descriptions or photographs submitted with the records. For 2009/2010 only 76 observations were confirmed, for 2010/2011 449. Particularly in the last winter, extra attention was paid to the occurrence of Taiga Bean Geese.
      The corrected trend, derived from the monthly counts, shows that Taiga Bean Geese numbers dropped after the series of cold winters in the mid 1980s. During that time on average 17,850 individuals were counted in cold winters (maximum 22,000 in 1986/1987) and 3100 in mild winters (Fig. 1). In the 1990s, seasonal peak numbers went down to on average 600 birds, further declining to an average of 200 after 2000. The highest number recorded after 1986/1987 was 1400 in 1991/1992. This decline is in line with trapping data from goose catchers, who did not catch any Taiga Bean Geese after 1986/1987, although the species is commonly used as live-decoy to attract wild geese to the catching site. Also sightings of ringed and neck-banded birds from the Baltic have not occurred since 1989/1990, confirming the lack of large influxes from the regular wintering range. Data from the platform www.waarneming.nl in the recent cold winters in 2009/2010 and 2010/2011 to a large extent confirm the pattern observed in the goose counts. In 2009/2010, an estimated 180 individuals were recorded (seasonal maximum during the monthly counts was 171). Numbers in 2010/2011 were slightly larger, i.e. 300 birds. This number exceeds the maximum based on the monthly counts (50).
      Data from international censuses also show that the species is currently in decline and winters increasingly in the north(east)ernmost part of its wintering range. We assume that this flyway-level decline and shift in wintering sites is the main cause for the major decrease observed in The Netherlands after the mid 1980s. The species is still an annual visitor, but numbers are small and in several winters do not exceed 100 individuals. Given its rare current status, we recommend that in future years any observation of Taiga Bean Goose should be given special attention with regard to identification. For this purpose, we also advise observers to check family status and flock structure of presumed parties of Taiga Bean Geese, and always use (and report) a combination of field characters to achieve a correct identification (Table 1). #### Tundra Bean Goose Anser serrirostris Taiga Bean Goose Anser fabalis

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