The mixing of the races of the Yellow Wagtail in Kenya

THERE is considerable controversy over the occurrence of certain east European and Asiatic races of the Yellow W a g t a i l (Motacilla flava) in Great Britain. Some ornithologists accept these records as examples of vagrancy while others claim some of the birds to be mutants of the local breeding race. The following notes on the Yellow W a g t a i l group on passage and in winter localities in Ea...