Well this article is just wrong. Most birds have monocular & binocular vision. The easiest way to understand this is, when you look at a bird and see the center of both of his eyes he can see you with binocular vision and when you can see only one of his eyes he can only see you with monocular vision. Interestingly enough most of us are aware that our pets have a blind spot behind them. But did you know they also have a blind spot directly in front of them? This spot is small. It extends from the beginning of their beak to about one inch in front of the beak. This goes a long way to explain why your pet may not like to be touched with small objects like a finger directly on the beak. He has to first trust the part of the object he can see. This field of view changes as the vertical plain changes. Knowing all this, I used to be baffled at how my macaws could consistently pick up something smaller than a grain if rice with a serge’s skill every time. If you won’t to know how they do it, you’ll need to put a grain of rice on your eyelashes and watch as they pick it up, in monocular vision of course, with the other eye closed. A safer way is to put the rice on a mirror laying flat and then watch the bird’s eyes in the mirror as he picks it up. The problem with this is he always sees two grains of rice. Or does he?

Mike Bross
Phoenix AZ

This is just sooooo annoying. Why did you have to ask that question at the end? Now I have to go find the rice! :)

If you look at the shape of a macaws head the narrowest point from his eye to the hinge point of the jaw. With his beak closed he can just see the edges of his lower mandible. As he opens his mouth the lower edge of the beak drops out of the way and the line of sight is actually slightly through his mouth. At this angle he can see the tip of his beak part of his tong and the complete edge of the lower mandible all this in binocular vision from the inside of his mouth. Once the upper and lower parts of the beak shear over each other the blind spot begins to return, or so I think. I also think this holds true for other species of parrot.
I learned some years ago from a vet that if you wonted your bird to open his mouth you could gently tap on his beak. If you try this you will notice the bird tilts his head back and opens his mouth. Most everyone thinks it’s so they can grab and chomp down on your finger. But assumptions are not always true. I have often had a hangnail or a splinter or just needed a manicure. A gentle tap on the beak is all my macaws need to examine my finger and fix the problem and most of the time they recognize what’s wrong with out me showing them. Its amazing how gentle and accurate they can be with a task like this So next time you tap or touch your birds beak and think when he raises his head its to bight, maybe he’s just opening the door so he can see who’s knocking.

Mike Bross
Phoenix AZ

Very interesting! Please shed more of your knowledge into the digital domain.