Wednesday, February 2, 2011

Northern Cardinal

The sight of a male cardinal on a frigid day always warms a birder's heart. Since the early 1800s, Northern Cardinals have expanded their range northward.  During this time temperatures have warmed and the species does well near human development (especially bird feeders).

Male Northern Cardinals pair with just one female.  Nevertheless, DNA studies demonstrate that up to 35% of cardinal nestlings do not share the same father. Both males and females feed the young, the males more than the females.  Brown-headed Cowbirds' laying their eggs in cardinal nests are a major problem for cardinals.  When they lay their eggs, female cowbirds remove cardinal eggs from the nests (Halkin and Linville. 1999).

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