Bean Goose Anser fabalis
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In autumn, Sweden is of special importance for the Bean Goose and especially for the western Taiga Bean Goose Anser fabalis fabalis as the majority of the population stages in Sweden for a period especially in October, smaller numbers at that time of the year being found in areas south of the Baltic, i.e. northern Poland and the Baltic districts of eastern Germany. Especially October has been found to be an important month for counting Taiga Bean Geese in Sweden as thefirst major migration to the south from Sweden occurs first in late October/early November or later.
Neck-banding of Bean Geese in Finland (breeding) and Sweden (staging) have shown that the Bean Geese in Sweden in October consists of two different cotigents at least. One group of birds apparently from more eastern breeding areas migrates into the country in the early autumn and stays for a period before leaving Sweden to the areas south of the Baltic with frosty weather in the autumn. The other part (around 30-40000 birds) stay in Sweden until winter, in mild winters they remain in the country, in hard winters they move on to avoid the snow to the southwest, nowadays mostly to Denmark, formerly to western Germany and the Netherlands. Spring migration includes smaller numbers, i.e. those remaining over the winter or wintering in Denmark.
October numbers first increased and reached a peak of close to 80000 birds in October 1989, numbers then decreased and between 41000 and 52000 have been counted in October witrh one exception. October 2007 showed once again another picture with more than 62000 Bean Geese counted.
During the years there have been marked changes in the distribution of the Bean Geese especially in October. During the first years SW Scania was an important area, the numbers here decreased and peak counts were noted at Tåkern, later numbers at Tåkern decreased, Kvismaren being the most important site, whereas very few reach Scania in October.
November numbers have showed a more steady level, normally fluctuating between 30000 and 40000 individuals even if some years have had 50000 or moreBean Geese, due to mild weather. January counts have been more variable reflecting the strength (or more correctly the snow conditions) of the winter, varying from almost no geese in the coldest winters to nearly 40100 in the last winter (2008).
With data only from Sweden it is difficult to intrepret the situation for the Taiga Bean Goose. During the peak years in was estimated that the total population was in the order of 80000 - 110000, but it most probable that the total population is lower now, around 80000, as indicated by data from countries south of the Baltic. A thorough analysis of the entire count data base for the Taiga Bean Goose will be undertaken in the near future. The somewhat higher counts in October 2007 may be due to a larger proportion of the Taiga Beans passing Sweden this year than the years before. There are no indications, unfortunately, for an increase in the total population of Taiga Beans.
The counts in November indicates that there has been no major changes in the western part of the population, i.e. those staying in Sweden (and Denmark) over the winter.
Smaller numbers of Tundra Bean Geese Anser fabalis rossicus are seen regularly during the autumn, mostly in Scania.
Annual totals (diagrams for October, November and January)
To Goose counts Gåsinventeringar
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Last updated 2008-08-15