Nearly half a mile away, a coyote is waking up from a nap by the main road in Point Reyes National Seashore.
As Dietrich brings the wildlife photo safari closer, the canine slowly stands up and ambles away through the thick brush, eventually stopping on a rock to stare back at us. A moment later, it vanishes into the towering grass. (Read about an extremely rare yellow cardinal spotted recently in Alabama.)
Seeing a coyote—one of North America's most successful predators, which has spread into every corner of the country in recent decades—is not that unusual on its own.
But when he saw the images from that April day, Dietrich was speechless: A bright pair of gray-blue eyes gazes back.
“I’ve never seen this,” says Juan J. Negro, a senior researcher at the Spanish Council for Research in Seville, Spain, who has studied animal coloration for over 25 years.
Unlike the exotic blues and greens of domestic dog eyes, which humans have selectively bred for around 8,000 years, coyote eye color lies strictly within the golden spectrum, he says. (Coyote pups are born with bluish eyes that transition to yellow by about six weeks old.)
Wild mammals and birds tend to have a consistent eye color, though in certain species—especially birds—individuals may have different eye colors based on sex, age, and readiness to breed.
"Deviants, or strange colors, arise from time to time as mutants,” says Negro, but a wild mammal with blue eyes like the coyote's could be as rare as one in a million.
It may not be possible to know the exact ratio, but National Geographic explorer Stan Gehrt, an urban coyote expert at the University of Ohio, can attest to its rarity. (See National Geographic Your Shot pictures of coyotes.)
“We have marked and handled over a thousand [adult] coyotes in the Chicago area,” he says, "and we’ve never seen any deviation from the eye color.”
It's also unlikely the Point Reyes animal is a hybrid with a domestic dog or wolf, a phenomenon that occurs in eastern North America but is rarer in the west.
Like Negro, Gehrt attributes this adult coyote’s baby blues to a genetic mutation—which, he notes, is entirely plausible due to the relatively small number of genes associated with eye color.
An Eye Toward the Future
Camilla Fox, founder and executive director of Project Coyote, a predator-advocacy nonprofit based about an hour from where Dietrich spotted the coyote, also supports the mutation hypothesis.
Neither she nor any of the members of Project Coyote’s science advisory board who reviewed the photographs had ever seen a blue-eyed coyote.
While some on the board are not convinced that the animal's eye color is truly blue, Fox says, “what’s obviously apparent is this is incredibly rare.” (See photos of albino and unusually white animals.)
Overall, Fox hopes the Point Reyes coyote will inspire viewers to appreciate how similar coyotes are to domestic dogs. Coyotes are generally not protected by law, and hunters and government agencies kill at least 400,000 a year in the United States.
“We love and adore one, and we vilify and persecute the other. And something’s very wrong with that picture.”