Benjamin Olson / Northern Saw-whet Owl (Aegolius acadicus) biologists aging individual by its feathers, Wolf Ridge Environmental Learning Center, Minnesota

Benjamin Olson / Red-tailed Hawk (Buteo jamaicensis), captive educational animal, Wolf Ridge Environmental Learning Center, Minnesota

Benjamin Olson / Johnson Lake and distant Lake Superior in autumn, Wolf Ridge Environmental Learning Center, Minnesota

Benjamin Olson / Northern Saw-whet Owl (Aegolius acadicus), captive educational animal, Wolf Ridge Environmental Learning Center, Minnesota