Some rodents produce urine and feces containing elements that reflect UV light. This may be beneficial for many reasons, including allowing them to see urine trails left by some prey animals such as mice and voles. Most birds are able to see ultraviolet (UV) light, which is invisible to humans. This isn’t some kind of strange dance. Raptors do this to triangulate an object and better determine how far away it is. If you watch a bird of prey long enough, you will probably see it bob its head from side to side, move its head around in circles, or even turn its head almost completely upside down. On the other hand, forward facing eyes are important for an animal that makes its living chasing moving prey. This eye placement works well for deer to see predators that try to sneak up on them. Notice that the deer’s eyes are much farther apart, almost on the sides of its head. Compare a raptor’s eyes with those of a prey animal, such as a deer. This helps them determine how far or close an object is. First, the birds have what is called binocular vision. Like many other animals that hunt for food, including humans, a raptor’s eyes face forward, which creates some overlap between what the right eye and left eye see. To help them do all of these amazing things, raptors’ eyes have many interesting adaptations. Raptors also use their eyesight to identify other members of their species and to avoid predators. In fact, scientists have shown that some raptors can spot medium-sized prey from at least 1 mile (1.6 km) away. That would be like spotting a rabbit across more than 17 football fields lined up in a row! If that weren’t impressive enough, birds of prey must be able to maintain focus on their prey while in fast pursuit and as they close in. Since most raptors are hunters, they must be able to see their prey, sometimes from great distances, and calculate just the right moment to strike. Think of the expressions “watching like a hawk” or “eagle eyes.” They refer to the amazing eyesight of all birds of prey, not just eagles and hawks.

Human prey eyes