Geografische variatie bij ganzen Deel 6 De Sushkins Gans Anser fabalis neglectus en de Buturlingans Anser (fabalis) carneirostris

In this paper a description of the mysterious Sushkins Goose Anser fabalis neglectus is given. Once a very common visitor to the Ufa-district (Russia), the Hortobágy-puszta (Hungary), the Tashkent-region (Uzbekistan) and probably also to Persia (Iran), neglectus has become a very rare bird in the course of the 20th century. According to Johansen (1951), Delacour (1954) and Voous et al. (1973) Anser neglectus should be treated only as a colour- phase which can appear in every type of Bean Geese, but this opinion is in opposition with the original description of neglectus (Sushkin 1895-‘97) from which it become clear that this goose not only differs from birds of the A. fabalistype by the pink colour of the bill and the feet, but also by means of morphological differences as well as by a different colour of the overall plumage. However, as P. Sushkin definitely described birds of a tundra-breeding type, during the first half of the 20th century it became clear that also a taiga-breeding type occurred. Examples of this type were shot in several locations all over Europe and were regularly caught as well by goose-fowlers in The Netherlands. During the past twenty years Sushkins Geese were regularly observed on many places in Western Europe as well as in several geese-haunts in the Baltic area and in the Pannonic region. Almost all the birds observed during the 1985-2003 period belonged to a taiga-breeding type, with characters of A. f. fabalis (58%) and A. f. Johanseni (35%). Only nine birds of the tundra-race rossicus and two birds (a pair) of the serrirostris-type were seen. As neglectus once was a breeding bird on the isles of Novaya Zemlya and Kolguyev and on the Siberian mainland in the northern Ural/Ob district, this might indicate the former existance of a range of Bean Geese with pink colour of the bill and feet, reaching from the Northern Atlantic isles ( brachyrhynchus) throughout Novaya Zemlya and Kolguyev (neglectus tundra-type) to the North West Siberian forestzone (neglectus taiga-type). Anyway, the fact that geese with neglectus-characters are regularly observed (not only single birds but also pairs, families with juveniles and recently even flocks) indicates the possibility of the existance of a (small?) population of birds of this type somewhere in the Western Palearctic. As no recent records of wintering flocks of Sushkin Geese are known from geese haunts in Europe, it is possible that the wintering region of these birds is situated somewhere in Asia. Apart from the Sushkins Goose neglectus, Bean Geese with a pink colour on the bill but regularly tinted, orange feet have been described already in 1902 by Buturlin. They became named Buturlin Goose after this author. Through the years, such geese were found also in some Siberian breeding areas as well as during wintering or migration throughout nearly the entire range of A. fabalis and A. serrirostris. However, they usually were found as individuals or occasionally very few birds together. They have never been seen in pure flocks of some tens or hundreds of birds. Therefore it seems most likely that birds of the carneirostristype actually must be the results of crossings between geese with orange bills and feet and birds with pink ones.