Tuesday, January 31, 2012

Chicken Vision

Betty can keep any eye on me--and still see what's going on around her.
Our chicken coop is about 50 feet from the house. When I open the back door, the hens almost always come running to see what I've got. But what has surprised me is that sometimes I'll be inside the house, and will just look through the window or door to check on them, and they'll come running.

If I'm outside looking toward the house, I can generally see if someone is standing right in front of the window if I look hard enough. If they are standing back from the window a few feet, I can't see them.

But even if I stand a few feet back from the window, the hens will still come running. And then they'll stand there looking directly at me, cocking their heads and training an eye on me as if to say, "I totally see you."

If I don't come out, Violet and Mabel will hop up on to the step in front of the door and peer up at me.

At first, I didn't think they could really see me. But their expressions are so intent--and they aren't just looking at the window, they are looking at my face, and are maybe a little annoyed that they came running all that way and I'm still standing inside. There's an air of expectant impatience about their glare.

If I stop and think about all their scratching and searching for small bugs and seeds, it seems pretty obvious that they must have decent vision. Curious, I decided to read up on chicken eyesight. I'd always heard their eyesight was poor at night, but how well do they see during the day? Is it my imagination, or are they using their X-ray vision on me?

Turns out, chickens do see well. In fact, they see colors that humans can't. Recent research revealed that chicken eyes are better "organized" than human eyes, and that this means they can see color better than humans. According to the author of the new study on chicken vision, Dr. Joseph C. Corbo of Washington University in St. Louis (WUSL) School of Medicine:  

“'The human retina has cones sensitive to red, blue and green wavelengths. Avian retinas also have a cone that can detect violet wavelengths, including some ultraviolet, and a specialized receptor called a double cone that we believe helps them detect motion,' Corbo adds. Additionally, when eating colorful fruits such as berries, the creatures need to be able to distinguish between poisonous plants and the real deal." 

In fact, chickens can see things that are moving so quickly they would appear as a blur to humans, and they can keep one eye on prey while keeping the other eye on morsels of food. This would explain how Violet can gobble up oatmeal while giving Mabel the stink eye at the same time.

I look out the window with new, well, perspective, on my chickens.

1 comment:

  1. That was interesting. I knew they must have good eyesight (they QUICKLY detect and peck at minute freckles (and scabs--eww) on my legs and arms) but I didn't know about them seeing extra colors. I am amazed at the speed and precision that they peck flowers or clover off of a stem. Right now mine are still in a brooder so I'll lower something into it and the "good part" is GONE faster than I can see it and they leave the stem behind.