Effects of Weather on Breeding Ducks in North Dakota

摘要

Relations between weather features and several aspects of the breeding biology are quantified for four duck species: mallard (Anas platyrhynchos), gadwall (A. strepera), blue-winged teal (A. discors), and redhead (Aythya americana). Data was obtained from two locations in North Dakota - the J. Clark Salyer National Wildlife Refuge, intermittently during 1936-68, and the Northern Prairie Wildlife Research Center's Woodworth Station during 1965-77. Arrival dates varied with mean temperature before and during the usual arrival period; early-arriving species were affected by early-season temperatures, and later-arriving species by temperatures later in spring. Precipitation during the breeding season may have prolonged nesting activities.