Monday, April 4, 2011

Redhead

Redheads pair up on their wintering range.  By 1 April, when this photo was taken at Circle Lake in Rice Co., many monogamous pairs have formed. Males, nevertheless, usually abandon their mates early during her incubation, retiring to loaf about and molt prior to the fall migration.

Redheads breed in Alaska, the western United States and western Canada.  When nesting, different female Redheads show at least three distinct egg laying strategies.  She may lay her eggs in her own nest.  Others lay eggs in other ducks' nests (both in Redhead and other ducks' nests), and then proceed to lay a clutch in her own nest.  Finally some females forgo raising their young altogether, laying all their eggs in foreign nests. This "facultative brood parasitism" has been shown to decrease the reproductive success of the host species. Redheads, despite their domestic laissez-faire, are usually outnumbered by other North American prairie-nesting species (Woodin and Michot 2002).

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