Tuesday, August 25, 2009

Photo Study of a Dead Cuckoo

Yesterday, I saw a Black-billed Cuckoo. While not a rare species, it can be a difficult bird to find, even during migration. Unfortunately it was deceased. This cuckoo was lying in the bushes outside my cousin's house.

The cause of death is unclear. There were no visible wounds, which rules out a predator, like a raptor or a cat. However, its neck is broken, and there is some sort of shiny fluid around the bird's face (visible more clearly in the photo below). It may have crashed into one of my cousin's front windows and died from impact. A second possibility, since there was heavy migration the previous night, is that the bird died from exhaustion and broke its neck upon hitting the ground.

This was an immature Black-billed Cuckoo, which is apparent from the buffy shading on its neck. The long tail feathers also do not have as bold of a black and white pattern as would be expected on an adult. Yellow-billed Cuckoos, by the way, have much larger white spots on their tails, making the tail pattern an easy way to identify a perched cuckoo if you cannot see its bill.

While Black-billed Cuckoos have much less rufous on their wings than Yellow-billed Cuckoos, they still retain some. Their rufous is hard to see in the field, as it blends in with the dominant brown, but in the hand it shows much better.

In contrast to the dark upper wing, the underside is creamy white.

I was sorry to encounter such an awesome bird in such unfortunate circumstances. However, it was interesting to see some of its features up close, in a way that is rarely possible outside of a banding blind or a museum collection.

For larger images and a few more photos, see the cuckoo set on my Flickr account.