WYMENGA E (1999) Egyptian Goose Alopochen aegyptiacus drowns chicks of Shelduck Tadorna tadorna. LIMOSA 72 (3): 106-107.

In July 1995 at Lake Yssel, off the Frisian coast, an Egyptian goose was observed drowning four chicks of a nearby pair of Shelduck. Despite heavy calls of the Shelducks the chicks were grasped and successively drowned. Though aggressive behaviour of Egyptian geese is well known, violent behaviour as in this case is hardly ever heard of. In Dutch literature one similar case was found, describing a pair of Egyptian geese in captivity, which drowned several birds among which were eight adult Mallards and two Upland Geese.

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