Wednesday, April 5, 2017

Eastern Bluebird

On 31 March, Erika and I watched a flock of six male Eastern Bluebirds make their way through a forest edge at the Whitetail Woods Regional Park in Dakota County. We were impressed by the brilliance of their blue.  Bluebirds appear even more brilliant to each other. They see ultra-violet light. Male bluebirds reflect this color especially well (Gowaty and Plissner 2015).

This bluebird shows a couple of interesting features. I expected only young bluebirds to show the yellow base to the bill. If you look closely, notice the white-tipped secondary coverts on the wing. In other thrushes, these tips are held-over juvenile feathers. I suspect this bird, therefore, is a bird hatched last year.

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