HART M T (1987) Short contributions: Joint migration of Whooper Swans Cygnus cygnus and White-fronted Geese Anser albifrons. LIMOSA 60 (2): 86-86.

On 16 March 1987 a formation of five Whooper Swans Cygnus cygnus and six White-fronted Geese Anser albifrons was seen migrating north. The wind was NW. The swans flew on the windward side of the formation, the geese on the leeward side. Birds were most probably on long- distance migration.

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