Mallard hatching from an egg cracked by freezing

R. J. Greenwood

doi:10.2307/4083468

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Mallard hatching from an egg cracked by freezing

R. J. Greenwood

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Abstract

The eggs of early-nesting waterfowl in North Dakota are frequently exposed to subfreezing temperatures. Mallards ( Anas platyrhynchos ) and Pintail ( Anas acuta ), normally the first ducks to arrive in the spring, begin limited early nesting in min-April. Nighttime temperatures during this period frequently drop below freezing, and late spring blizzards are not unusual.

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R. J. Greenwood. 1969. Mallard hatching from an egg cracked by freezing. https://doi.org/10.2307/4083468

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