Brood Parasitism

The Brownheaded Cow Bird is one of those species that uses the nests of other birds to lay its eggs, leaving it to other bird parents to raise its young.  It evolved this strategy because it was so busy following the bison herds on the Great Plains of North America, that it could never make it back to a nest of its own to lay eggs, so it took whatever opportunity that presented itself.

The Cow Bird is an open country bird, so it's Interesting that it's become a problem here in Virginia until you stop and consider the rather extreme deforestation that's gone on for the last 150 years.  Anyway, it's a threat to the songbird species on the east coast now, and I'm bringing this up only because there's a lot of these "little evidentiary things" that really start to add up to a big fuckin' problem after a while.  Kinda important to pay attention to 'em.

So actually, I dunno what to think about having found this egg on the top rail of the pool fence behind the house today - are Cow Birds kinda dumb?  Do they stop wherever they happen to be and lay an egg when they just can't go any farther?  Or...what?