It being July, the first wave of nestlings is out and independent, and the parents are going back for their second broods.  This means that confusing young birds are out and about, leaving many of us who are not yet experienced leafing through our books with great uncertainty.  So, first things first:  you see a Robin-sized bird foraging on the ground.  It’s kind of a nondescript greyish-brown color, with a longish, straight dark beak.  It makes scratchy, grating calls and may be associated with a couple others very like it.

You actually know this bird – and you probably think you know it so well that you barely pay attention to it.  So, why is it so unfamiliar?  Well, let’s see a more familiar family group:

Yes – this odd, unfamiliar bird is in fact the young of that ubiquitous and annoying pest, the European Starling.  The adults have that familiar dark plumage and a long, straight,yellow bill, but the young don’t look like much of anything familiar.  The hint of spectacles, and the variable streaking on the belly make them look intriguing, but hard to place.  They do have the shape, that familiar waddling walk and the long bill (even if it’s dark), and they often hang out with adults, begging for food, though, so eventually it becomes clear.

OK, here’s another one – you see a Robin-sized (well, almost) bird foraging on the ground.  It’s kind of a nondescript greyish-brown color, with a stubby, rather conical beak.  It also has a heavy head, and looks kind of ‘bull-headed’ as it moves around and perches.  It doesn’t make much in the way of sounds, though.  You can see streaking underneath and a whitish throat, and looking at the bill, your first thought is that it might be some sort of odd House Finch or something related.

You actually know this bird – and you probably think you know it so well that you barely pay attention to it.  So, why is it so unfamiliar?  Well, let’s see some more familiar family groups:

Got it?  Here are the actual parents:

Yes – this odd, unfamiliar bird is in fact the young of that ubiquitous and annoying pest, the Brown-headed Cowbird.  Adapted to following roaming herds of Bison by just dropping the eggs into available nests, this rather interesting bird causes problems for the unwitting adoptive parents, as you can see above.  The evolutionary ‘arms race’ between nest parasite and host has been a fertile subject for study for a long time, and cowbirds have their own particular habits that make them worth studying.