An owl pays close attention

Predators tend to be more successful if they go hunting when their prey are out and about, which is why many of them hunt at night. That includes the great gray owl, though its keen senses of hearing and sight help it hunt equally well during the day. It is highly successful at capturing small rodents such as voles and pocket gophers, which account for up to 90% of its diet. The great gray owl perches in a tree overlooking an open area and uses its hearing to locate prey, which it can detect even under 2 feet of winter snow. Then it glides silently from its tree and dives to grab its quarry, sometimes leaving marks of its outstretched wings in the snow. Naturalists say this is often the only indication that these extremely reclusive creatures are in an area. This large bird is well adapted to a life of hunting: The soft feathers of its wings enable silent flight, the feathers of its facial disk direct sound waves toward its asymmetrically positioned ears, and its night vision is outstanding thanks to a high density of rod cells as well as the tapetum lucidum that reflects and makes the most of any residual light. (In fact, owls have the best night vision of any animal.) What’s more, it’s able to swivel its head by 270 degrees. After a night of precision hunting the owl flies to its tree, blending in perfectly with the bark thanks to its plumage, and settles in for some shut-eye.