Clouded leopard cub cuddling with zookeeper

When you see a photo of someone feeding an adorable baby zoo animal a bottle, maybe it makes you a little jealous. How come your job isn't that much fun?

But for zoo staff, it's much more complicated than that. Often, having to hand-raise an animal is not great news because it means something went wrong with mom or baby, and it's not easy to substitute for natural parental care. Other times, to keep a species going, people actually do more for babies than nature would. Whatever the reason, it always takes a lot of extra work and planning.

Intervening with Caution

For most zoo animals, hand-raising only happens when there's a problem. "We always strive to have the dams raise their offspring — that's always our No. 1 goal," says Dave Bernier, general curator at the Lincoln Park Zoo. "There are times when we have to intervene, and all of those times are based on the well-being of the offspring or the dam."

A baby may need to be removed from the mother because it's not doing well, but it could also be because the dam's health is at risk and raising the baby while recovering would be too stressful, Bernier says. Other times the mother may not be caring for the baby properly. At Lincoln Park, the staff recently hand-raised a klipspringer, a tiny African antelope, because the mom was being aggressive toward it. Although sometimes it's natural for animals to be a bit rough with their young, the staff decided not to take chances.

Bringing Baby Back Home

Whatever the reason for removing a baby from its mom, the solution isn't spur-of-the-moment. Bernier says his zoo always has a contingency plan in place when breeding an animal, even though they don't usually need it. "A birth management plan always has this component — when would we intervene, and what would we do?" he says. "We do this research and have this conversation ahead of time."

And the plan needs to be long-term, taking into account what kind of lives the adult animals lead. For some it's relatively simple, like the klipspringer, which doesn't need to learn to get along with a group. "They're not really a herd animal; they live in pairs or they live solitarily, so [hand-raising's] not a huge impact on their development," he says.

But with more social animals, the less time they spend away from their group, the better. In some cases, keepers can find a way to care for the baby without removing it. That's what they've done at Lincoln Park with herd animals such as the Arabian oryx, in which species the young naturally spend their time hiding while the mother comes and goes. "We're able to separate everyone away from the kid, and we can go in and offer the bottle and leave," Bernier says. "The only time the animal is separate from the group is when we're doing the feeding, so there's very minimal impact."

Calf klipspringer and zookeeper

Other cases require more effort. When a baby gorilla was injured at the zoo, the staff came up with ways to reduce the impact of her recovery from surgery. "We housed her separate from the other gorillas but kept her in direct proximity to her family group so she was never out of sight of other gorillas," Bernier says. And while it might seem irresistible to coo and cuddle with a baby ape, the staff also tried to minimize her exposure to human activity like talking.

Keepers taught the young gorilla to come to the mesh of the enclosure and take food, so they could supplement her diet when she rejoined the group. That allowed them to return her to her family as early as possible, which is always their goal. "Especially with mammals and critically with social animals, we try to minimize the amount of time that the animal is away from its dam or conspecifics," Bernier says. "We work hard to get everyone stabilized and work toward introducing those animals back into the group."

Providing a Better Upbringing

Although many babies are hand-raised as a substitute for natural mothering, there are cases in which keepers provide care that the young wouldn't get in the wild. Many bird species lay two eggs but routinely raise only one baby to adulthood, either because the parents give only one nearly all the care or because the chicks compete, eventually to the death. But in the zoo, keepers pull the second chick and raise it.

They take the step especially if the animal is critically endangered or extinct in the wild, like the Micronesian kingfisher. "In that population, every individual has a high value, so we wouldn't want even a natural process like chick competition to get in the way," Bernier says. However, they do the same thing for the ones that aren't rare, because zookeepers care about individuals as well as species. "A nestmate that is being under-attended to or forced out of the nest, we will also hand-raise that animal because the individual animal's welfare is the critical concern," he says.

Some babies that wouldn't get any parental care at all in the wild get individual attention from keepers. Reptile eggs are normally removed from enclosures and artificially incubated, resulting in tiny creatures that need special care in captivity — like the smooth little green snakes that the zoo is hatching for release for a conservation project. The zoo is making sure to have insects small enough for them to eat — and nutritious enough for a growing baby. "The nutritionists have designed diets for the insects that we feed out," Bernier says. "We have to feed the insects the right food to make sure they're a proper diet and not just empty calories [for the snakes]."

Creating Tolerant Adults

While Lincoln Park, among other zoos, only hand-raises babies for health reasons, there are cases elsewhere in which other considerations come into play. For instance, with the clouded leopard, hand-raising has not only reduced high infant mortality but has also proved to be important to breeding the animals in captivity. The difficulty has been that when paired for mating, one of the leopards often would end up dead.

"With clouded leopards, the big problem is the males are generally about twice the size of the females," says Karen Rice, supervisor of carnivores and anteaters at the Nashville Zoo. "And they're so agile they can go just about anywhere — up, down, sideways. There's a lot of chasing. It's not a pretty scenario."

The clouded leopard problem has been addressed by pairing them when they're young and by hand-raising them so they're safer to work with. Rice says that mother-raised clouded leopards are very easily stressed, but it was discovered that hand-raising produced calmer, more tolerant animals. Since it's relatively safe to be in the enclosure with the hand-raised cats, keepers can keep a close watch and intervene if necessary when the animals are introduced to one another.

Another reason animals might be hand-raised to be tolerant of people is for use in education programs, as Rice has done with Eurasian lynx. The result is not an animal the general public can pet, but people get to see it closer up than would otherwise be possible. "Our education department uses one of the lynx that was born here. He's on a halter and a lead, and they have him onstage to show behaviors," she says.

Giving Mom What She Needs

Despite those exceptions, when it comes to most animals, the goal is to hand-raise fewer babies. Bernier says while that goal has been achieved over the course of his career at Lincoln Park, it may be partly because they're having fewer babies in the first place as the result of the nationwide coordination of breeding programs, which focuses on breeding only when needed, taking space and diversity into account. But there are cases in which zoos have gotten better at understanding what the mother needs to raise her young successfully on her own, like knowing when to separate the breeding pair for naturally solitary species, as was the case for the three-banded armadillo.

"The females need to be separated from the male quite a bit before the birth," Bernier says. So even if the staff is not sure a female is pregnant, the pair is kept separate, after mating, for the whole gestation period. Then if the female does give birth, they know what to do next. "We've got a protocol set up for how to manage her in the first few critical days, in order to make sure that she's calm and she feels comfortable, so she'll put the kid in a nest and leave it there and nurse it instead of constantly moving it around."

Staying Up All Night

Fewer hand-raised babies is a goal that is probably good for keepers as well as animals, because raising babies means a lot of extra work.

"On the one hand, they're adorable, but talk to me at midnight or 1 in the morning … " Rice says. "This year, we didn't breed any of our clouded leopards, and I'm more rested than I've been in years."

Most babies need round-the-clock care at first, which at Lincoln Park means keepers being at work in the middle of the night. At the Nashville Zoo, Rice takes the babies home with her several days a week, with a coworker taking them the other days. They need care for about three months, and she recalls one year that they had three litters: "I had five cubs at my house on different feeding schedules."

And if you still look at those cute photos and wish you had a job raising baby zoo animals, keep in mind that doing so is not actually anyone's entire job. Unless you're a clouded leopard keeper, hand-raising a baby animal is a rare event — and you don't get time off from caring for your other animals to do it. "This is on top of the work they have to do otherwise, and they're having to adjust their schedule to come in at midnight and do feedings," Bernier says.

Also, remember: It's not just about feeding, but also cleaning up the end result — which, with some babies, gets rather personal. Some need physical stimulation to eliminate, which the mother would do by licking or grooming. "The human caretaker would have to provide the same type of stimulation by hand with a damp warm cloth," he says.

Still, it has to be said that, yes, keepers generally think that hand-raising a baby animal is totally cool.

"It's stressful, but they find it immensely rewarding," Bernier says. "They're willing to put in that extra effort, and they'll do it with a smile on their face."