Some Aspects of Breeding Biology of the Blue-Winged Teal

Abstract

This study on blue-winged teal (Anas discors) was conducted at Delta, Manitoba. In addition to supporting previous works showing that air temperature governs the start of nesting, this study also contends that unseasonably cold air temperatures (mean temperature below 41 [degree]F or minimum temperature of 30[degree]F) occurring after the nesting season has begun can result in a reduction in the nesting effort. Initial blue-winged teal clutches ranged from 10 to 13 eggs. In renests (clutches begun after June 4) there was a significant trend toward progressively smaller clutches with advance of the season. The normal incubation period was 23 to 24 days for this sp. nesting in the wild, and the incubation period for eggs under artificial incubation was 24.3 days.