For the first time in the National Zoo's history, keepers are hand-rearing a sloth bear cub away from her mother to keep her safe and healthy. (Michael Ruane/The Washington Post)

For the first time in the National Zoo's history, keepers are hand-rearing a sloth bear cub away from her mother to keep her safe and healthy. (Michael Ruane/The Washington Post)

When the National Zoo’s female sloth bear, Khali, delivered three cubs last December, she consumed one of them right after it was born.

Carnivores do this in the wild when there is a sick offspring. A deceased cub in the den can draw predators, the zoo said.

But a week later, when Khali consumed a second cub, keepers feared for the third. So for the first time in the zoo’s history, keepers took a sloth bear cub from its mother to raise by hand.

Three months later, after weeks of incubators, midnight feedings and quiet sessions in a rocking chair, the sickly cub has grown into a healthy 11-pound sphere of black fur and relentless curiosity.

On Tuesday, keepers showed off their foundling as it clambered around its enclosure and downed a warmed bottle of formula.

1 of 10 Full Screen Autoplay Close Skip Ad × Zoo keepers raise sloth bear cub View Photos The National Zoo workers decided to take the newborn from its mother after she ate her two other sickly babies. The keepers have nurtured it back to health. Caption The National Zoo workers decided to take the newborn from its mother after she ate her two other sickly babies. The keepers have nurtured it back to health. Keepers are hand-raising this female sloth bear, seen March 18, 2014, at the National Zoo. The mother, Khali, gave birth to three cubs Dec. 29. She ate two of the cubs — it’s not uncommon for carnivores to ingest stillborn cubs or live cubs if they or the mother are compromised in some way. The keepers decided to hand-raise the surviving cub, which was sick. Linda Davidson/The Washington Post Buy Photo Wait 1 second to continue.

The zoo’s sloth bears are not the celebrities that their fellow bears, the giant pandas, are. Adults are shaggy, long-nosed, gap-toothed consumers of bugs.

A full-grown sloth bear can vacuum 50,000 termites a day with its flexible lips. And the zoo’s sloth bears like nothing better than a yummy handful of big, brown meal worms.

Not the thing to draw oohs and aahs from the panda crowd.

But sloth bears are highly intelligent animals, who keepers say have complex emotions — including fear and outrage — and vibrant personalities, and who enjoy watching videos.

They are far more energetic than the indolent giant pandas, their advocates say.

And the keepers are proud to have saved the animal, which comes from one of the world’s vulnerable species.

The three cubs were born Dec. 29. The first cub was eaten by the mother 20 minutes after it was born. The second was consumed Jan. 6, and the third was “pulled” from the mother a short time later.

1 of 15 Full Screen Autoplay Close Skip Ad × D.C.’s zoo babies View Photos Take a look at some of the animals born at the National Zoo. Caption Take a look at some of the animals born at the National Zoo. Keepers are hand-raising this female sloth bear, seen March 18, 2014, cub at the National Zoo. The mother, Khali, gave birth to three cubs Dec. 29. She ate two of the cubs — it’s not uncommon for carnivores to ingest stillborn cubs or live cubs if they or the mother are compromised in some way. The keepers decided to hand-raise the surviving cub, which was sick. Linda Davidson/The Washington Post Buy Photo Wait 1 second to continue.

“It’s a serious decision if you’re going to pull a cub,” said Mindy Babitz, a sloth bear expert at the zoo. “We want cubs to be raised by their mom. That’s an ideal situation. We’re doing everything we can to be a surrogate mom to her. But we’re not bears.”

Keepers extracted the frail, one-pound newborn from the den while the mother was in another area. They took it to the zoo’s animal hospital and placed it in an incubator.

“She was actually very sick when we pulled her,” Babitz said. The cub was suffering from cold and some kind of infection. She was given fluids and antibiotics and placed on a heating pad.

Babitz said Khali, who previously reared healthy cubs before she came to the zoo, may have consumed the other two because she sensed that all three were sick. Khali is in good health now. The plan is to eventually return the cub to its mother, or another adult sloth bear.

“It’s normal for mom to consume her cub if it’s compromised in some way, or if the mom is compromised in some way,” said Babitz, who has a doctorate in animal psychology.

“Life is tough in the wild,” she said. “If a cub were to pass away and you were to just leave that carcass laying around, that would attract a predator. And that’s not safe for mom.

“When she consumed that second cub, that’s what alerted us to, ‘Okay, something’s probably wrong,’ and that’s why we went ahead and pulled the third one,” Babitz said.

The zoo has seen this phenomenon before. A lioness who delivered a litter of cubs Jan. 24 consumed one that was stillborn.

“It seems cruel,” said Tony Barthel, a zoo curator. “But rearing a little cub or several cubs is a huge energy drain on these animals. And if you think about their life in the wild, they really cannot afford to spend energy needlessly. . . . It’s all about protecting mom for the future and next round of cubs.”

The surviving cub, which has not been named, was kept in the hospital for four nights and in an incubator for five more weeks. The keepers then had to step in.

“Anything from feeding to cleaning . . . to holding, bonding, snuggling,” Babitz said. “When you’re working with a bear, they’re so complex emotionally and cognitively and socially, and they need that bonding . . . and whether it comes from their own mom or human doesn’t really matter at that age.”

It was a 24-hour-a-day job. Babitz and others often spent the night on a futon in an office near the den with a computer video monitor trained on the cub.

“If she wakes up and starts crying, we can run right in and take care of her,” Babitz said. “She’s still getting a bottle in the middle of the night. The other thing is: She’s a baby. She has bad dreams. She gets scared. She starts crying, and she needs someone to comfort her.”

Sloth bears are native to India, Nepal and Sri Lanka. They are so named because they were sometimes mistaken for sloths, Babitz said. Both have long claws. There are only about 10,000 sloth bears left in the wild, down from 20,000 eight years ago, the zoo said.

They are often captured for the dancing bear trade and for “bile farms,” where their gall bladders are tapped for bile used in traditional medicine practices, Babitz said. “It’s horrible,” she said.

The zoo has five sloth bears, and there are only 47 in North American zoos.

“The average person has never heard of a sloth bear,” she said.

“It’s very rewarding to know that I’m contributing to the conservation of the species,” she said.