Can you find the bird in the photo below?
The camouflage function of feathers is fascinating. I think the Hermit Thrush has a combination of several kinds of camouflage: cryptic coloration, disruptive coloration, and countershading. In the first, the coloration of the feathers is similar to the environment in which the bird forages or nests causing her to blend with her surroundings. That would be the soil, sticks, rocks and decaying matter covering the ground--all that gray and brownish neutral you see around the bird that she matches so well.
Disruptive coloration describes the broken blocks of color, such as the specks on her breast, that cause her to blend with the environment even more and not stand out as much as she would if solid brown. "Countershading" is the dark on top and white underneath phenomenon that is nature's way of taking away the appearance of depth. Without motion to give her away, the thrush flattens and disappears. Above you see her where I often find her first, hiding in the shrub or foraging underneath in its shadows.
And then, she runs out onto the lawn in pursuit of an insect.
Here's where you will notice something interesting. Hermit thrushes often forage on the ground with a "quivering" foot , tapping the ground in a strategy that is believed to stir insects. In the image below, you can see one foot is lifted.
And below, she appears to be listening....for insect movement? Also notice her lifted right foot.
Hermit thrushes generally nest in higher elevations and more northern states. I am curious about this individual since migration is said to occur in March and early April. It is now mid April and she's still hanging around. I am more than happy for her to stay.
Links and resources:
Cornell All About Birds on the Hermit Thrush. Be sure to listen to its song.
More on the hermit thrush
Beautiful series.
ReplyDeleteBeautiful bird. My wood thrush has returned to the woods next to my house and is singing his little heart out. I love that bird!
ReplyDelete