Sunday, April 8, 2007

First Bronzed Cowbird

I got out for about 3 hours this morning in the unseasonably cold weather. Near the end of Braeburn Glen I got this picture of the first Bronzed Cowbird I've seen this season. Actually I saw it on a wire from across the creek and wasn't sure what it was. So I climbed down into the creek bed, crossed, climbed up, and endured a neighbor's barking dogs while I verified what it was and got a few pictures. (The angle is a little strange but you can see a little bit of the bronzy color, the puffed out neck feathers, and the red eye that are characteristic of this species.) Bronzed Cowbirds and Brown-headed Cowbirds are the two species of cowbirds that occur locally. Brown-headed is much more common and is a year-round resident. Bronzed is only here in the summer in very small numbers. Austin is just about as far north as it occurs. American cowbirds are like European cuckoos -- they are nest parasites. The females lay their eggs in other birds' nests and let the other birds incubate the eggs and raise the chicks. This behavior probably came about because these birds used to follow migratory herds of American Bison. So they never stayed in one place long enough to build a nest and raise their own young.

On my way back an Osprey flew over, headed downstream. And I ran into a few nicely sized mixed species foraging flocks of little songbirds. They were mostly Yellow-rumped Warblers and Ruby-crowned Kinglets. (Some of the Yellow-rumpeds were in beautiful breeding plumage.) But I also saw a few Nashville Warblers, an Orange-crowned Warbler, a couple Blue-gray Gnatcatchers, Chipping Sparrows, Carolina Chickadees, and Black-crested Titmice. All-in-all, a nice morning!

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