A Mandarin duck has gone missing, and New Yorkers are losing sleep over it. (Bradley Kane/@BirdCentralPark)

The Mandarin duck was minding its own business in a pond in New York’s Central Park when, with the snap of a few viral pictures, it became a celebrity.

The rare duck, a colorful creature native to East Asia that mysteriously appeared on the water last month, was like a zebra among horses, stealing the show with its ruffled auburn sideburns, purple breast and iridescent crown. Hundreds flocked to the park with cameras around their necks to catch a glimpse of it, standing in lines that wrapped around the pond as if it were the star of a well-organized meet-and-greet.

The curious onlookers kept coming for days — until Monday, when nobody could find the duck.

It wasn’t there on Tuesday, either. So when David Barrett, the creator and manager of the Twitter account Manhattan Bird Alert, reported early Wednesday that “our MANDARIN DUCK” had gone missing, a frenzy ensued.

It was as though New Yorkers had lost a collective pet.

“We lost an attorney general today, but somehow the missing duck became a top story on Twitter,” said Barrett, author of “A Big Manhattan Year: Tales of Competitive Birding.” “Non-birders are going crazy about it.”

Theories emerged. Some feared the duck had been stolen. Others feared worse: that it had been eaten. Some even wondered whether Russians had kidnapped it or, inevitably, it had been deported.

“Justice for the Central Park mandarin duck,” one New Yorker demanded on Twitter.

“Setting up an automatic email reply for self care until i hear news confirming the mandarin duck is safe,” lamented another.

“Crushed to hear the #MandarinDuck has disappeared,” said another.

The level of concern for the Mandarin duck has intrigued Barrett, who said he has been “immensely surprised” by the duck’s celebrity, as it can be difficult to interest people in birdwatching.

But Barrett said there is probably a rational explanation for the duck’s disappearance. He said he is not concerned that the duck has been eaten or is in danger. The duck was “getting along” with the other regular ducks, appeared healthy and, most obviously, Barrett said, can fly.

It probably just went somewhere else.

“I don’t think anything nefarious happened,” Barrett said. “Ducks are ducks. They like to fly — they like to move around to find an environment they like better, to find some food it prefers. And we don’t think someone would have taken it, because it can be very hard to do that. They’re not easy to catch."

The New York City Department of Parks and Recreation agreed. “While we’re happy to have had him visit our parks, it’s important to remember that at some point he may leave New York for warmer temperatures,” the department said in a statement to CBS New York.

Since it was first spotted near the pond in Central Park on Oct. 10, the Mandarin duck has been seen at different bodies of water around the city. At one point it was in the Hudson River near a Manhattan boat basin on Oct. 25. A few days later, it returned to its usual spot in the pond.

The fascination with the duck, Barrett said, appeared to arise out of the mystery of its appearance in the first place — the curiosity about where it had come from.

Barrett and other birders do not think the duck is wild, or that it migrated to Central Park from East Asia. That is clear, Barrett said, because it has a band around its leg.

Birders think the duck was raised in captivity, he said. The birder community thinks its owner either got tired of caring for it and released it in Central Park or that it escaped.

Either way, both possibilities indicate that the Central Park Mandarin duck may not be well practiced in typical duck migration patterns.

“In general, ducks are migratory. Wild ducks are,” Barrett said. “But this duck is domestic, and so it’s very likely he never had the chance to migrate.”

So would it survive a New York winter? Matthew Dodder, a California-based birdwatching instructor, said the duck would easily survive, as it is built to survive the cold winters of northern Japan.

Dodder said Mandarin ducks, which can sell for $150 to $300 per pair by breeders online, can thrive in a variety of habitats. He added that the Mandarin duck of Central Park is unlikely to migrate as far south as other birds might.

“He’ll be okay,” Dodder said. “[Central Park] is a pretty safe place, if you’re not afraid of the people."

Perhaps that was why the Mandarin duck left.

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