When Do Cowbirds Figure Out They Are Cowbirds?

Not a question of earth shaking importance, just idle curiosity born out of too many hours watching the bird feeder.

Our cowbirds are the brownheaded variety, and they remain here all year round. This past summer I noticed the occasional cowbird coming to the feeder with their apparent adoptive parents, usually some sort of sparrow couple. The cowbirds were old enough that the parents weren’t feeding them, but there still seemed to be a family unit of sorts.

Fast forward to winter. Now all the cowbirds are hanging out together, with half a dozen at a time crowding on the feeder at a time. Aside from wondering why we suddenly have an uptick in the cowbird population (in past winters, we’d have one or two mixed in with the grackles and starlings, and I’d hardly notice them at all in the summer), I’m trying to figure out when the cowbirds decided, “Wait–I’m not a sparrow! What am I doing hanging out with all these sparrows?”

I assume when they leave the nest and are out on their own. They will mingle with other species, but would tend to congregate where others of their own kind do.

They wouldn’t sound like a Sparrow or look like a Sparrow so why would they continue to associate with Sparrows?

Well, that’s what I would have thought, but this summer I did see some that appeared to still be with adult sparrows. They were old enough to be identifiable as cowbirds, and old enough the sparrows weren’t going around sticking food in their mouths–in other words, old enough to feed themselves, but maybe still young enough to require guidance?

Imprinting can be a very strong inherent behavior. Perhaps when they become sexually mature they will seek out their own kind…

I suspect they never have that kind of revelation. It’s probably more like “Hey, these cowbirds are way cooler than sparrows. I wonder if they’ll hang out with a sparrow like me.” and then later “Wow! I’m the luckiest sparrow in the world to be accepted by all these cowbirds.”

Sooner or later, though, a couple of them will want to try out the reverse cowbird.

Thank you all for your thoughts on the matter. I swear every time I look out at the feeder there are more of them. Either the weather has done something to draw them this way or our neighborhood had the most gullible swallows ever this summer.

In a brood parasitic species, strongly & permanently imprinting on the adults you encounter when hatched would seriously impair your ability to produce offspring.

It seems likely that a cowbird chick’s instincts are telling it: “For as long as these suckers will feed me, I’m a sparrow. As soon as that ends, I’m a cowbird.”

Um, sparrows, not swallows.:smack:

I doubt cowbirds have much of a sense of self. Have they done any mirror tests with them? I also don’t see why a cowbird couldn’t have both an instinct that causes it to imprint on its adoptive parents for feeding/early socialization, and an instinct that drives it to mate and socialize with cowbird-shaped things.

Just you wait until the gullible swallows* get together with the reverse cowbirds. Then you’ll see some hot feeder action!:eek:

*I saw them at the Fillmore West in '71. Changed my life. :cool: