Saturday, June 8, 2013

Black-crowned Night-Heron

On our return to Minnesota from South Dakota, rain drove mercilessly across the highway. How do birds keep dry in the rain? Theoretically, birds keep dry by oiling their feathers from secretions from an oil gland on their rumps. Water slides off the oil, leaving the birds dry. I write “theoretically,” because this Black-crowned Night-Heron is looking drenched—its wing coverts are becoming matted and water is dripping off the tip of its bill.

Black-crowned Night-Herons are found around the world, except Antarctica and Australia. They are usually hard to see because they feed at dusk, night, and at dawn. They eat fish and other aquatic animals. Because of this diet, night-heron tissues accumulate contaminants such as DDT. Populations have rebounded with the advent of modern environmental protection, and currently numbers in North America appear to be on the increase (Hothem et al. 2010).

I have previously blogged about night-herons.  This photo was taken in central South Dakota along Highway 12.

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