セグロカモメ
Mallards are also preyed upon by other waterside apex predators, such as the grey heron ("Ardea cinerea"),the European herring gull ("Larus argentatus"), the wels catfish ("Silurus glanis"), and the northern pike ("Esox lucius"). Crows ("Corvus") are also known to kill ducklings and adults on occasion. Also, mallards may be attacked by larger Anseriformes such as swans ("Cygnus") and geese during the breeding season, and are frequently driven off by these birds over territorial disputes. Mute swans ("Cygnus olor") have been known to attack or even kill mallards if they feel that the ducks pose a threat to their offspring.