Orange Alert: What Caused the Colors on This Snowy Owl?

Scientists who have studied owls for years struggled to explain the bird’s curious plumage. “In over 35 years of study, we have found over 300 nests and banded over 800 chicks,” Denver Holt, director of the Owl Research Institute in Charlo, Mont., said in an email. “We have never seen any plumage aberration, or anything like what is in the photos of the owl.”

Kevin McGraw, a bird coloration expert and biologist at Michigan State University, shared a surprising hypothesis: The owl became orange as a result of a genetic mutation driven by environmental stress, such as exposure to pollution. Dr. McGraw said in an email interview that samples from the bird were needed to test that and other hypotheses.

“We’d need to get feathers from this bird to understand the nature of the unique coloring,” he said. Geoffrey Hill, an ornithologist at Auburn University and a co-author with Dr. McGraw of a book about bird coloration, shared his interpretation. “It seems unlikely that it has spontaneously produced red pigmentation via a genetic mutation,” Dr. Hill said.

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Dr. Weidensaul offered his own suspicions about the bird’s hue. “The most likely explanation is that it was de-icing fluid at an airport, since some formulations are that red-orange color,” he wrote in an email.