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USGS · 70182082

Aggressive encounters between tundra swans and greater white-fronted geese during brood rearing

Craig R. Ely·David A. Budeau·Una G. Swain
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Abstract

Interspecific aggression in waterfowl (Anatidae) is relatively common (McKinney 1965; Kear 1972; Savard 1982, 1984), but interactions leading to mortality of one of the combatants are rarely-observed in the wild. A recent debate (Livezey and Humphrey 1985a, 1985b; Nuechterlein and Storer 1985a, 1985b; Murray 1985) has centered on the proximate and ultimate causes of interspecific territoriality and killing in steamer-ducks ( Tachyeres spp.), a group of large-bodies antids. We report here aggressive encounters between Greater White-fronted Geese ( Anser albifrons ) and Tundra Swans ( Cygnus columbianus ) during brood rearing on the Yukon-Kuskokwim Delta, Alaska, which on two occasions resulted in the death of a White-fronted Goose gosling.

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Craig R. Ely, David A. Budeau, Una G. Swain. 1987. Aggressive encounters between tundra swans and greater white-fronted geese during brood rearing. https://doi.org/10.2307/1368496

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