Brown-headed Cowbird

This nest was found built between the chairs of the pavilion in the wildflower garden of the Desert Botanical Garden in Phoenix. I don't know how long the chairs were there, perhaps a couple weeks or a month. They were set up for parties and special meetings.

A bird decided it would be a good place to raise her young. There was probably a lot food around from all those parties. The expert birders at the garden decided it was probably a Northern Mockingbird who built the nest. Mockingbirds are loud, chatty birds who imitate the sounds of other birds and sometimes machines, and they aren't afraid of people. Well, that's obvious from the location of the nest.

Anyway there were three broken, but beautiful Mockingbird eggs and one slightly smaller, unbroken mystery egg. Why was it so different, we all asked. Well, after much measuring and looking in books, and having serious scientific discussions, it was decided that the smaller, unbroken, egg was a Brown-headed Cowbird egg.

Now the plot thickens. Cowbirds lay their eggs in other bird's nests and then fly off never to be seen again. Talk about child abandonment. Anyway, most birds don't seem to notice a slightly different looking baby in their nest and happily raise them. Sometimes this is hard to watch when a tiny Black-tailed Gnatcatcher is feeding a baby larger than itself.

The theory is that Cowbirds evolved with the buffalo and followed the herds across the plains. They didn't have time to put down roots, or build nests. So they did the best they could and let other birds raise their young.

A darker part of this theory, is that the Mockingbird eggs may have been purposely broken by the Cowbird. So three fewer Mockingbirds and one more Cowbird. This happens to other native birds, so the Cowbirds may be helping lower the numbers of our native birds.

I find it hard to dislike them. They are beautiful birds that make a very pleasant tinkling sound. I often hear them on my walks. I hear their sweet bell-like sound and look up to see one or two of them, sitting very majestic on top of a tree or power-line. I don't want to think about the fact they they are probably just looking for a good nest to abandon their kids in.