It is 9:30 a.m. in the nursery at Chicago's Lincoln Park Zoo, and a keeper is trying to change the diaper of a six-week-old baby orangutan.
"Eeeeeeeeeee! Ooo-ee, ooo-ee, ooo-ee!" the baby gives out a high-pitched squeal that sounds something like a broken slide whistle. Lying tummy down in her tiny diaper, she clings to the changing table with long, hairy fingers.
"At this age, she would still be clinging onto her mom's chest," says Diane Mulkerin, manager of the children's collection at the zoo. "It's very disruptive to put her down on her back, so we change her on her stomach and she feels more secure."
The keeper picks up the 4-1/2-pound orang, who immediately quiets down and starts peering around the room with big black eyes. Long, fuzzy red hair pokes up from her head like a sweater with static cling. As always, her strong fists tightly grip the keeper's blue nursery smock.
Ms. Mulkerin and about seven other zoo keepers have been hand-raising the baby orang - feeding her bottles around the clock, burping, diapering, and cuddling her - ever since she was born on Dec. 27. Her mother, Batu, failed to care for her.
The job of these "zoo nannies" is as important as it is challenging: Orangutans are a highly endangered species. About 35,000 of the gangly, rust-colored primates live in trees in the tropical rain forests of Borneo and Sumatra in Southeast Asia. But their numbers are declining as logging destroys their habitat. Some are poached for pets.
Zoos around the world are home to 900 orangs, but they are aging. So the young Batu, who is 10, and her newborn daughter are especially valuable for breeding.
Zoo nannies like Mulkerin must walk a fine line in raising the precious infant orang. On one hand, they must constantly comfort, stimulate, and meet the needs of the tiny primate. But on the other, they must be careful not to teach human traits. Their ultimate goal is to return the ape to a group of orangutans.
Lori Perkins, head of the Orangutan Species Survival Plan under the American Zoo and Aquarium Association, explains:
"Twenty to 30 years ago, we understood very little how important it was for these animals to have contact with their own kind from a young age," says Ms. Perkins, who manages the study, breeding, and placement of orangs at zoos across the United States. "Most of the orangs were hand-raised. But we found out that these hand-raised animals were much less likely to raise their own kids."
In primates, the long relationship between mother and offspring is an extended course in how to be an adult. If the mother-and-offspring bond is not formed, certain social skills - especially maternal ones - have little chance of being passed on.
Batu may not be a great mom because she was partly hand-reared by humans and so missed some important teaching from her own mother. Batu also rejected her first baby, Mukah, a male born two years ago.
But Batu could learn to be a better mother, thanks to a new idea: maternal training for orangs. Carol Sodaro, the lead keeper at the Tropic World at nearby Brookfield Zoo, created the first successful program to train reluctant orang mothers to care for their babies.
In late 1992, Ms. Sodaro began working with Sophia, a feisty, 12-year-old orang. Like Batu, she had ignored her first baby. Using simple verbal commands like "lift," reinforced with treats like bananas and frozen-juice cubes, Sodaro trained Sophia to pick up an infant-like object, hold it upright, and put it to her breast.
At first, the curious and irascible Sophia crushed dozens of empty bleach bottles and tore up a few teddy bears used as surrogate babies. But soon the novelty wore off, and Sophia, who like all orangs is highly intelligent, began responding gently and promptly to Sodaro's cues.
Just in case Sophia's training failed, her mate, Ben, was also taught to tote around an "infant" on his abdomen and bring it to keepers for bottle feeding. Although such behavior doesn't exist among male orangs in the wild, the good-natured Ben - a 1990s kind of guy - cooperated willingly.
In July 1993, Sophia gave birth to a daughter, Kutai. At first she paid little attention to Kutai, dragging her around the cage clinging onto her leg. After 24 hours passed without any nursing, Sodaro intervened with her cues. Sophia responded immediately, nursed the baby, and has been "a model mother" ever since, Sodaro says.
"The potential of this [training] for animals in captivity is very great," Sodaro says. (Remember Binti? She's the female gorilla at Brookfield who last year picked up a boy who fell into the exhibit and carried him to keepers. Binti also had some maternal training.) But even if Batu takes a motherhood course, keepers say it will be too late for her to raise her baby. The zoo is searching for a new family for the infant.
The best immediate choice would be an adoptive orangutan mother who is producing milk. But "good, lactating mother orangs" are hard to find, says Mark Rosenthal, curator of small mammals at Lincoln Park. An easier option is "peer rearing," or pairing the baby with another orang its own age and raising them together.
Back at the nursery, the baby orang is growing fast and seems content for now with human caregivers. She likes to chew on rubber teething rings, roll over, and clutch a stuffed panda. Sometimes, she rides in a front-pack padded with blankets.
"She's a very happy baby," says zoo vet Robyn Barbiers.
Tips for Zoo Nannies
SOME dos and don'ts when caring for a baby orangutan:
* DO wear a furry vest for the orang to cling to. It may keep it from exercising its strong grasping reflex by tugging at your hair or neck.
* DO often let the orang hang from your hands. Try tossing it onto your back or holding it upside down. Unlike human babies, orangs are incredibly agile. Their long arms and hook-shaped hands and feet are designed for tree-dwelling.
* DON'T talk "baby talk" to your orang. Instead, let it hear, smell, and see other orangs as much as possible. This is vital. It will help the orang get used to being with its own kind.
* DO plan to carry the orang most of the time. In the wild, infants ride on their mothers for years, even up to the age of 10, when they reach maturity.