KIST J (1959) The occurrence of Greylag Geese Anser anser red beaks subsp. in the Netherlands. LIMOSA 32 (4): 201-205.

In summary, I believe the following to determine: 1. It is a sheet of ornithological tale. that in our country by migrating, plaster-income and wintering Greylag Geese all a carrot-colored (orange-yellow) have beaks. 2. In our country come to the Greylag Goose beak three types: a. geese with a (seemingly) the whole orange-yellow beak Western European Grey Goose, mainly plaster-income by tractor (already from early September), not whether occasionally winters with us; b. geese with some orange, some pink variegated red bill, the Polish Grey Goose , regularly in the winter months and winters with us plastering; c. geese rose red bill with a whole: the R c hey sis us Greylag Goose, regularly. but in small number in our winter months and winters plastering. 3, The Russian Greylag Goose differs from the Asian Greylag Goose Ansel anser rubrirostris as established by Delacour described, since it is in the field did not noticeably lighter and grayer in color than the normal (western) Greylag Goose. 4. The three mentioned types of Greylag Geese in our country in families or groups of families, from which the conclusions could be drawn. that we are not dealing with a phenomenon of individual variation, but with three (or more) geographically and morphologically distinct forms The occurrence of Greylag Geese Anser anser red beaks subsp. in the Netherlands

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