Cowbirds aren’t among my very favorite birds because they’re egg-dumpers: they don’t build nests; the female finds a nest with eggs in it and lays hers there, as well. So when the eggs hatch, the cowbird hatchling, with its voracious appetite, will generally end up getting all or most of the food, starving the other babies—or he’ll be so much larger physically that the smaller babies end up getting shoved out of the nest as he grows. Either way, they’re lazy birds in terms of raising their own (or, more accurately, NOT raising their own) and, as I said, not among my favorites.
They ARE, however, protected by the Migratory Bird Treaty Act, as they are a native species.
In the video clips below, you can see how much calmer he is, even first thing in the morning before his breakfast. In the second clip, he’s full and drowsy but still interested in wiggling fingers!