VOOUS KH (1972) Short announcements: An abnormal population of Great Tits. LIMOSA 45 (1): 90-92.

A description is given of a pale-coloured specimen of Great Tit Parus major, belonging to a small population group of similar birds, living for several years amidst normally coloured birds of this species in a restricted area in Hilversum, Netherlands. The bird, a ~ (wing 75, tail 69 mm) is conspicuous by a reduction of yellow in the plumage, giving the upperside a predominantly pale bluish grey appearane, whereas the under parts are dirty yellowish buff, darker and greyer on the body sides. A very similar coloration is in the whole distributional area only present in populations from Crete (Parus major aphrodite) and Israel (P. m. terraesanctae), but still these birds have on the whole a somewhat brighter, though equally pale, coloration, particularly on the under parts in which the yellow tinge is more vivid, less suppressed as in the Hilversum specimen. Three practically similar birds have been found by the author in the collection of the British Museum of Natural History, originating from Jiimtland, Sweden, where they have been collected in January and February 1957. They are equally conspicuous aberrations in the Scandinavian population. Attention is called for the interesting aspect of these seemingly trivial cases of individual variation: genetical changes resulting in virtually identical plumage colorations can apparently occur independently within the enormous range of the otherwise homogenous populations of Parus major major. Besides, the result apparently resembles closely the genetical composition of populations living in other parts of the species' range.

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