A male grizzly bear relocated from the wild 12 years ago due to dangers created by human encroachment on his mountain habitat has died at the Bronx Zoo, where he was a popular attraction, zoo officials said.

The 13-year-old bear named Jughead died last Friday while undergoing surgery for an abdominal abscess, said Dr. Patrick Thomas, the zoo's curator of animals.

He is survived by his brother, Archie, and two female grizzlies, Betty and Veronica, age 14, also rescued in 1995, living at the zoo's Bear Overlook compound.

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"Jughead was a wonderful, charismatic animal and he will be missed by all of our staff and visitors," said zoo director Jim Breheny.

The four bears, named for characters in the "Archie" comic strip, were rescued from Montana and Yellowstone National Park in Wyoming after being judged "nuisance" bears that had become too accustomed to humans and posed a potential danger.

In 2004, the zoo bears were featured in a special edition of Archie Comic Publications.

Grizzlies can stand 8 feet tall and weigh as much as 1,000 pounds, and are noted for being aggressive, unpredictable and dangerous.

Once ranging the American west from Mexico to Alaska, they have been reduced nearly to the point of extinction by civilization's encroachment on their habitat, and now are concentrated in federal reserves in Montana, Wyoming, western Canada and Alaska.

Classified by the U.S. Interior Department as "threatened, " grizzlies have remained fairly stable in the past 20 years, probably numbering fewer than 1,000 animals in the western United States, Thomas said.

Loss of habitat and isolation, preventing gene exchange, are the biggest threats to their survival, he said in a statement provided by the zoo.

The U.S. Fish and Wildlife Service and the Wildlife Conservation Society, based at the Bronx Zoo, collaborate in euthanizing "nuisance" bears, or moving them to isolated areas or to accredited zoos.

Zoo officials said Jughead had been treated for a possible bacterial infection after becoming lethargic and anorexic over two months, and underwent surgery after doctors discovered the abdominal abscess, but did not survive.

A necropsy was planned, zoo officials said.