The public (and J.K. Rowling) favored Luna among the five name choices.

With a popularity bump coming from author J.K. Rowling, "Luna" was picked as the name for an orphaned sea otter pup being raised at Chicago's Shedd Aquarium.

Chosen over Cali, Ellie, Poppy and Ana, the name was announced on "Good Morning America" today (Dec. 12). It replaces the far less personal "Pup 861."

Luna was underweight and just a week old when wildlife authorities rescued her on a California beach in early October. [See Photos of Luna the Otter Pup]

The otter named Luna now weighs 11 lbs. (Image credit: Shedd Aquarium)

After a short stay at the nearby Monterey Bay Aquarium, the orphaned pup was sent to a more permanent home at Shedd Aquarium, where her caretakers report that she is in good health and hitting all of her developmental milestones. The pup now weighs 11 lbs. (5 kilograms) and she's diving, foraging for food and grooming on her own, according to the aquarium.

The photogenic pup has since earned many adoring fans — among them "Harry Potter" author J.K. Rowling. Last month, Rowling tweeted a picture of the otter being measured at the aquarium with the caption: "'What would you like to be if you weren't a writer?' An otter weigher." The post was retweeted more than 18,000 times.

A few days later, the aquarium opened its naming poll. Staff members at Shedd Aquarium picked the name options, which are all derived from the names of habitats of southern sea otters. Luna is based on Half Moon Bay in California, which is close to the beach where the pup was found. But the name is also in Rowling's novels: Luna Lovegood is a witch, and friend of Harry's.

An aquarium staff member tweeted at Rowling to ask for the author's name preference. She responded, "Luna, of course!" A plurality of the 10,000 voters agreed.

Southern sea otters were nearly driven to extinction, but they have made a comeback off the coast of California. The creatures remain listed as a "threatened" species on the U.S. Endangered Species List. The U.S. Geological Survey recently estimated that the population of southern sea otters is about 2,944, barely up from last year's estimate of 2,941 individuals.

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