An extremely rare sighting of a yellow rail in Colorado sets bird-nerd world a twitter.

It might have been his car engine ticking away the summer heat that Eric DeFonso heard when he switched off the ignition in the Monte Vista National Wildlife Refuge on July 12.

But it was still early morning, and cool. He hadn’t driven that far from his campsite. And DeFonso had spent hundreds of hours listening to bird song CDs in his car, so he wasn’t about to get this wrong.

The ticking persisted as DeFonso approached some bushes seeking the true source, ignoring the gaudy trills of red-winged blackbirds. Time to draw on a rare superpower. DeFonso is a stone-cold bird nerd, playing and memorizing online bird songs as his downtime hobby. 

Tick-tick-tick … tick … tick-tick-tick. Like the “60 Minutes” stopwatch had the hiccups. 

It was a yellow rail. Always desired by birders. Almost never seen. When birders describe the yellow rail, “secretive” and “elusive” are never more than a word away. (“Birding” magazine, 2007: “one of North America’s most elusive birds”).

Reticent everywhere else, and basically nonexistent in the Rocky Mountains.

DeFonso, who had been thunderstormed out the day before on a high country birding survey for his day job, hit the record button on his laptop. At once giddy and disbelieving, he sent sound clips to a friend who literally wrote the book on bird songs. (“Peterson Field Guide to Bird Sounds of North America,” if that works for you.) 

Believe it, his friend immediately wrote back. 

Thus did Eric DeFonso become the first person to have credibly observed a yellow rail in Colorado in more than 100 years — through sound alone, a perfectly acceptable “get” for species that never show. 

Dozens of birders, Subarus stuffed with back copies of “Audubon Magazine” and phones crammed with the Sibley Guide to Birds app, immediately descended on the refuge to hear what DeFonso and others agree is a “life” bird. Meaning it’s the first time Coloradans can get a local yellow rail for their list, and likely the last. 

“To an outsider, it must seem strange that so many people would drive so far to hear such an underwhelming sound coming from a wetland, with no bird in sight,” DeFonso wrote on Facebook at the end of his big week. “But to a birder, that sound is music to one’s ears, and represents a really remarkable natural occurrence.”

Yellow rails populate southern Canada and parts of the very northern tier of America. It winters on the Gulf Coast and has no reason to tour the San Luis Valley. The last documented case of a yellow rail in Colorado was at Barr Lake near Brighton.

And since the 1906 event was a century before Facebook birder groups, DeFonso is comfortable calling his encounter “the first live, chasable yellow rail in the history of Colorado birding.”

“LIFER!!!! Absolutely amazing find, Eric. Thank you,” wrote fellow birder Gary W., who heard DeFonso’s Facebook call and made it to Monte Vista by Thursday, confirming the sound immediately.

“Clearly a special event,” said Andrew Farnsworth, a senior researcher at the Cornell Lab of Ornithology, in an email. 

No one has a photo yet, nor do they expect to get one. Birding ethics mean leaving the creature be as much as possible, and never flushing a species just to get the image. Online full-frontal captures of a yellow rail are rare, and unlikely from the bushy marsh cover of the southern San Luis Valley. 

DeFonso has gone back to the high country to continue his annual remote bird count for his job, happy to picture the valley filled with dozens of SUVs racing toward the refuge to pay respects to the yellow rail. Or rail(s); there may be two, or at least one very active bird who knows how to circle out of sight and set an audience on fire with dreams of a breeding pair.

On Saturday, the Cornell Labs rare bird alert system logged 13 soundings of the Colorado yellow rail. On Sunday, another 10. DeFonso encourages seekers to show up early in the morning, or in the twilight hours he describes with the rarely seen word “crepuscular.” 

DeFonso closes his story with a “Breakfast Club” fist in the air to bird nerds everywhere. “Keep studying your bird sound recordings, kids,” he said. “Someday it will pay off.”

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