A Humboldt penguin named Mochica has died at age 31 at the Oregon Zoo in Portland, zookeepers said in a news release.
Before the bird was euthanized Saturday, he had been the oldest in the Oregon Zoo's Humboldt penguin colony — and one of the oldest penguins in the world, they said.
The zoo said Mochica, hatched July 6, 1990, was "hand-reared, a standard practice at the time."
"But Mo, as he was known for short, grew up different from the other chicks. More than any penguin in the zoo's large Humboldt colony, he enjoyed spending time with people, often choosing keepers' quarters over the company of his fellow birds in the Penguinarium," the zoo wrote.
Mochica was euthanized at 31, about 11 years older than a Humboldt penguin typically lives in the wild, because zookeepers said his old-age ailments had become too numerous for palliative care.
He had a cataract in one eye, haze in another and arthritis in his hips, birdkeeper Travis Koons said.
"He was just a very old bird. It was hard for him to see and, at times, difficult for him to walk," he said.
Koons said Saturday's euthanization was "an incredibly sad day for his care team and for everyone who spent time with this amazing bird."
The zoo said it hopes Mochica's three decades of work as a "distinguished seabird ambassador" will be reflected in greater care for the at-risk habitats of Humboldt penguins — the coastlines of Peru and Chile — and suggested using the Seafood Watch App while shopping for seafood.