SWENNEN C (1974) Short announcements: Aberrant colours in the Eider Somateria m. mollissima on the island of Vlieland. LIMOSA 47 (1): 51-51.

During the years 1963 - 1973 partial albinism with scattered white feathers on head and neck, sometimes also on the wing, was found in about 4% of the studied breeding females (n = 1,842). Conspicuously light-coloured nesting down, once even snow-whitel, in otherwise normal coloured ducks, occurred in about 0.5% of the breeding females. A nest with notably light-coloured down had already been found in 1923, when the young colony counted 10 breeding pairs only (Drijver, 1924). Individual birds, once observed to show whitel spots or with strikingly light down, presented the same phenomena also in the next years. There are no indications that there is any relationship with age. Three leucistic breeding females were found (less than 0.1 %). These birds were' very pale, nearly white. The down of these birds was pale too; on the other hand the eggs had a normal colour. Leucism was observed once in a male. Common Eider Somateria mollissima

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