How to see this 'feathered serpent'—one of the world's most dazzling birds—in the wild

There’s an Aztec king’s headdress — the last of its kind — in the collection of Vienna’s Weltmuseum Wien, made with nearly 400 iridescent emerald tail feathers from the quetzal bird, which have been stitched into a half-moon fan. So rare are the feathers and so vivid — despite being more than 500 years old — that the artefact, reputedly from Mexico, is reportedly worth $50m (£38m). Yet nothing could possibly trump the real bird in front of me.

“They used to call it the feathered serpent,” says my guide, Carlos Serrano Navarro, as we watch the bird flit between moss-cloaked branches heavy with bromeliads in the high-altitude cloud forest of San Gerardo de Dota. Its nickname makes sense: the quetzal is such a prized species for birdwatchers because of its long tail, which can reach up to a metre and give the impression of a writhing snake in flight.

It’s little wonder the Aztecs and Mayans thought the quetzal so precious. “It was forbidden to kill this bird as they believed it was a representation of one of their gods — Kukulkan,” explains Carlos, as he describes the Aztec and Mayan feathered serpent deity. The quetzal’s feathers were gathered from the forest once they were shed, and then traded for food, clothes or even gold.

Sporting a ring through his nose, my 28-year-old guide tells me he’s been tracking quetzals for a decade; he learned from his father, who’s also a guide. “My great-grandfather was a pioneer. He came here in the 1950s to farm cattle when the Costa Rican government was giving away land,” he says, never taking his eye away from the bird. His great-grandfather soon realised the value of San Gerardo was in its birdlife and he became one of the first to set-up a guesthouse aimed at birdwatchers.

A two-hour drive south east of San José, San Gerardo is a six-mile-long, mountain-ringed valley off the Pan American Highway with no through-road. A healthy population of quetzals lives here year-round, thanks to wildlife protections and the abundance of wild avocados, their favourite food. Sightings are almost guaranteed. “We think we have 100 pairs of quetzals on this six miles of road and, of course, many more deeper into the forest that we’ve never seen,” says Carlos.

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He points to a line of coyotes picking their way along a precipitous mountain path, high above the quetzal’s avocado trees. Traffic signs line the mountain road warning of tapirs crossing, though they’re hard to spot. Meanwhile, tiny volcano hummingbirds, no bigger than field mice, buzz around branches, and big, black guan birds circle and land on the grassy lower slopes. Carlos spots a northern emerald toucanet, its large, hooked beak unmistakable as it hides in a bowery.

The shimmering flash of the quetzal’s tail grabs my attention again. It settles on a branch and Carlos’s tripod-mounted spotting scope brings the bird into sharp focus: a punk-like mohawk head crest and blood-red breast reveal themselves, the latter rising and falling as it calls for its mate — a ritual that Carlos says is as regular as clockwork.

“Their feathers are like prisms,” he tells me. “If you look at one under a microscope, you’d see layers of keratin and melanin, and that’s what’s refracting the light.” To prove his point, he produces a quetzal tail feather that he has pressed between the pages of a birding book. Sure enough, the feather I’d been convinced was emerald green becomes sapphire blue, then golden as it shifts in the sun. It’s a chameleon-like ability almost worthy of the great feathered serpent Kukulkan. I can see why the Aztecs valued the quetzal more than gold.