Results of study of pre- and post-breeding moult in captive White Wagtails hatched in the Central Ural and in the lower Ob, and of post-breeding moult in the wild in the Central Ural and lower Ob are discussed. It is shown that the birds from these regions differ by the pre-breeding moult extent, by photoperiodic conditions of moult and the possible wintering latitudes that correspond to the photoperiod intervals of moult. The first stages of the post-breeding moult, irrespectively of population origin, are under the endogenous control. Later stages are controlled by photoperiod in White Wagtails from the Central Ural, whereas the moult of tundra wagtails is probably totally endogenously controlled.
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