The Color of Birds' Eyes

Peer into the world of birds, and eyes of many different colors peer back. While eye color isn’t tied to one group of birds or another, a common pattern is a change in eye color as immature birds grow to adulthood. Bald Eagles, Ring-billed Gulls, and ducks such as goldeneyes and scaup have brown eyes as youngsters, and yellow eyes as adults. Red-tailed Hawks reverse this pattern, with their eyes changing from yellow to brown. And the yellow eyes of a young Cooper’s Hawk, pictured here on the right, turn deep red as they reach maturity.

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