As we have recently been publishing articles on how birds can hear and smell, this week we will dive into how well birds can see, and illustrate some interest facts about their eyesight.
What is most likely their most important sense, a birds eyesight is essential for not only their day-to-day activities but for their overall survival.
How Birds Use Their Eyes
Arguably the most important function of a bird’s eyesight is their ability to clearly see and navigate during flight, but their most acute and developed sense does serve them well in other areas as well. Unlike humans, birds have four types of colour receptors in their eyes, giving them the ability to perceive a huge range of colours as well as the ultraviolet range of the colour spectrum.
Bird’s eyes are equipped not only with more light receptors, but they are built with additional nerve connections between their photoreceptors and their brains. This gives birds the speed they need to process their environment during flight, evade predators or forage for food.
The true strength of a birds eyesight lies in their ability to detect and process motion and detail, and in comparison to humans, birds can see up to three times better than us in this respect.
The position and shape of the eyes on a bird varies across different species but is also an integral part of their eyesight and their field of range for sight. The placement of the eyes on birds of prey actually give them a better binocular vision, allowing them to accurately judge distances, while nocturnal species will be equipped with tubular eyes, not as many colour receptors allowing them to operate effectively under low lighting conditions.
Most other bird’s eyes are positioned either quite far apart or on either side of their head, allowing them a wider field of view and the ability to nearly see what is directly behind them.