Those Beautiful Bird Eyes

Birds are renowned for their exceptional and remarkable vision, a gift that allows them to perceive the world in ways we can only imagine. The eyes of birds have reached perfection, superior to any other animal. Birds obtain more information about their environment through their eyesight than is available to any other living thing. Some birds can even see ultraviolet light, which is invisible to the human eye. Their eyes are finely tuned instruments, capable of detecting the slightest movements and capturing the most vibrant colors. It is as if they see the world through a kaleidoscope of colorful hues.

The eyes of birds collect data about direction, distance, size, shape, color, three-dimensional depth, and motion of an object. This gives our birds a great advantage in the wild. Their incredible range of vision is due to the placement of the eyes on the sides of the head. This fact, coupled with the shape of the cornea, allows for wide-angle vision. Birds can focus straight forward with both eyes, but also see sideways just as effectively. Their peripheral vision is extremely keen, especially relating to moving objects. Birds have a high density of photoreceptors in their retinas, allowing them to see with incredible clarity and detail. This sharp vision comes in handy for spotting prey from great distances or navigating through dense forests with ease.

Although a bird's eyes seem small, proportionately, they are much larger than human eyes. The only visible portion of a bird's eye is the cornea. The largest part remains hidden. The eyelashes are small feathers, not hairs. A bird's eyes are wide-set and have amazing mobility in its neck and head. If you are very observant of your bird, you will notice the head does not always point to the object the bird may be looking at. If your bird tilts his head at you, he may just be looking at you from another angle. 

Many birds have a third eyelid called a nictitating membrane, which helps protect their eyes and keep them moist while maintaining visibility. This delicate membrane allows them to blink without losing sight of their surroundings. While humans have three types of color receptors in their eyes (red, green, and blue), birds have four. This extra color receptor allows them to see a wider range of colors and even perceive ultraviolet light. For birds, the world is a much more vibrant and colorful place than we can imagine. You may have noticed your bird prefers certain colored toys or foods. They use that super vision to find food, avoid predators, select a mate, and choose a great nesting site in the wild. Did you know that pet birds blink their eyelids 30-60 times a minute? So quickly, you will probably never see.

Unlike humans, birds don't have the luxury of snoozing with both eyes shut. Birds have a unique way of resting called unihemispheric slow-wave sleep, where one half of their brain remains alert while the other half rests. This allows them to keep an eye out for predators while catching some Z's. Now that is some great multitasking!

Next time you see a bird soaring through the sky or perched on a branch, take a moment to appreciate the incredible vision that allows them to navigate their surroundings with such precision and beauty. Or, if your own bundle of feathers seems to be giving you a very special look, remember you are being vividly seen by your bird. Or if your feathered friend is looking intently at something you do not see, just remember your bird is seeing something so small or in a totally different direction than you may see.

Those beautiful bird eyes truly are a marvel of nature. So now you know, a bird's eye view is quite a view indeed.

(Thanks to Toby Grey, Cosmo Macaw, and PJ Amazon, for their awesome eye modeling.)