Yellow Warblers and Cowbirds at Malheur

Although driving your car is the only practical way to bird Malheur National Wildlife Refuge, getting out and walking parts of the refuge makes it possible to get shots you would otherwise miss, like this shot of what appeared to be a young Yellow Warbler [UPDATE: After an email from John and pretty well convinced that the top bird is NOT a warbler, the beak is too thick to be Warbler] and Brown-Headed Cowbird.

young Yellow Warbler and Cowbird

I must admit I was totally confused by the shot at first. [UPDATE: Perhaps confused was the correct state and I shouldn’t have tried to make a connection between the nearby Yellow Warbler and these two.] I thought that it had to be two young birds because of their behavior, particularly the fact that they stayed put rather than flying away when I shifted position to get a better shot through the heavy foliage. Most adults would fly away if they thought you were really interested in them, whereas chicks tend to freeze in place, hoping to avoid detection.

It was pretty clear that the two were different kinds of birds, though at first I thought it might be the heavy foliage that made them seem to be different colors and they were both immature Yellow Warblers and that was why this Yellow Warbler was so intent on attracting my attention away from them.

Yellow Warbler

Although I saw adult Yellow Warblers both days at Malheur, none came nearly as close as this one did, trying to attract my attention. Naturally I obliged by following it away, getting the best shots I’ve managed all the while.

It wasn’t until I got home that looked more carefully at the “chicks” that I realized the bottom bird was a Brown-headed Cowbird, a bird that lays its eggs in other bird’s nests, including the nests of Yellow Warblers. Although I’d heard about the phenomena, it really didn’t register until I looked at this photo. There’s quite a trove of information on the internet about the phenomena, it turns out.

Since Cowbirds often lay their eggs in the nests of Yellow Warblers, Yellow Warblers are often able to recognize that it is not their egg and they build another nest over the top of the nest with the egg to avoid hatching it. This mother, at least, didn’t seem to distinguish the difference between her own brood and the cowbird and was raising both as her own.

Seems kind of like a reverse Ugly Duckling fairy-tale, doesn’t it?

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