On most birds, the eyes are arrange on the sides of the head, which is why they can see a large portion of their surroundings at any one time. Indeed the woodcock's eyes are so far apart that they have 360°vision. The drawback with having eyes positioned far apart is that the area that is seen by both eyes simultaneously-something that is necessary if a creature is to have binocular vision-ends up being relatively small. The birds have to compensate for this by continuously moving their heads from side to side. This results in enough separate visual information being received by each eye for the brain to be able to use it to construct an integrated, three-dimensional image.
Many birds also have very large eyes, which gives them good vision even in dim light, and there are a large number of birds that are able to see ultraviolet light in addition to the usual colors. This can be of benefit both for finding food and a partner.
With its eyes on the side of its head, the black-tailed god wit can even see enemies approaching from the rear.
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