A brown head with a body of some sort of lavender.

But cowbirds are terrible creatures.

I only make moral judgements about one species. And it is exponentionally the most terrifyingly destructive organism on the planet.

Cowbirds have a nasty habit of laying their eggs and other birds’ nest.

I had a strange bird on the deck last week and made an effort to identify it. Turns out it was a recently fledged cowbird and it was being fed by a pair of Carolina Wrens.

Brown-headed Cowbirds are brood parasitic - meaning they lay their eggs in the nests of other birds. In all cases, they are laid in the eggs of smaller birds. The young cowbirds gather all of the attention of the host nest's adults and starve out the host's young.

In my case, the cowbird was being fed by a bird less than half its size and the wrens were probably working themselves to death to feed the bird that killed their young.

Having said all of this, cowbirds do this because they had historically followed herds of grazing animals (e.g., buffalo/bison, antelopes, etc.) and this didn't leave a lot of time for proper nesting - so they displaced the young of other birds who would raise cowbirds as their own.

I try not to attribute human characteristics to that which is not human. Thanks for providing the non-moralistic explanation for cowbirds' behavior.

I took the kids on an outing once when they were fairly young - my son might have been 5(?) and his sister a bit older.

Someone in the group spotted a Blue-gray Gnatcatcher heading to a nest then realized there was a very young cowbird in the nest. Gnatcatchers a really small birds and the cowbird was stuffed in the tiny nest.

My son was INCENSED. He wanted me to climb out there and get that bird out of the nest. The nest is like 40' off the ground and hanging over a rock-lined creek - impractical and impossible.

In addition to seeing this firsthand, I also learned that cowbirds know where they lay their eggs and will check on the nest to see if "their" hatchlings are doing well. If you take the egg out of the nest, they'll destroy the entire nest and anything else in it.

Before we nearly wiped out the Buffalo.

The historical range of the cowbird prior to European settlement was restricted to the open short-grass prairies of the Midwest. Presumably as a result of large-scale deforestation, introduction of cattle, and other activities associated with European settlement, the cowbird's range expanded rapidly eastward and the species was widespread throughout the eastern U.S. by the late 1800's.

A similar expansion happened in the west during the 1900's resulting in their distribution being spread throughout southern Canada and the lower 48 states. Cowbird abundance has continued to increase dramatically throughout the breeding range since 1900, possibly due to greater overwinter survival from an increase in food supply (residual agricultural grain) and increases in reproductive success from exposure to new, vulnerable host species.