VENEMA P (1989) Short contributions: Joint migration of geese with other species of waterfowl. LIMOSA 62 (2): 92-92.

Whooper Swan Cygnus cygnus Greater White-fronted Goose Anser albifrons Within over 4000 records of migrating geese, 53 flocks (1.3%) of two or more geese species were found. Seven records (0.2%) of joint migration of geese with other waterfowl are described. Given the habitat choice, joint migration seems to occur less frequently than expected. Differences in flight speed are suggested to be the main factor.

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