The Mother’s Day surprise awaiting Lincoln Park Zoo curator of primates Jill Moyse was fitting.
Overnight Sunday in the zoo’s Regenstein Center for African Apes, Rollie, a female gorilla born at Lincoln Park 22 years ago, had given birth to an apparently healthy male, the 53rd gorilla birth in the history of the North Side institution.
“It’s like when a (human) mom has a kid,” she said Tuesday from in front of the habitat for the zoo’s western lowland gorillas, a critically endangered species in its native Africa. “Even though this isn’t my first gorilla, I was really shocked and very excited.”
Video footage of the habitat showed the birth taking place at exactly 2 a.m., an event that appeared as matter-of-fact as other bodily functions.
And although just two days had passed by Tuesday, the zoo had seen enough healthy behaviors to feel confident inviting the press in to have a look at the young one, estimated to be 4 to 5 pounds and as yet unnamed.
Those behaviors included nursing by the infant, witnessed by staff before 8 a.m. on that first morning; appropriate bonding by the mother, who has been holding the baby close to her chest since the birth; and the presentation behaviors staff trained Rollie for so that caregivers would be able to get a good early look.
During the 250-day gestation, “we do a lot of maternal training,” said Moyse. “‘Bring your baby to the mesh. Let us touch your baby. Let us see your baby.'”
Another impetus to show off the birth was to get things back to normal for the gorillas, including taking advantage of warm weather by letting the troop into the habitat’s outdoor portion, said Dave Bernier, general curator for the zoo.
“We got a really good look at this kid right away,” Bernier said. “We feel like he’s on a really good trajectory.”
The zoo has two western lowland gorilla troops, a bachelor group and the one centered on silverback Kwan, 30, the father of the newborn. This is the second gorilla Kwan and Rollie have produced, following Nayembi in 2012, who remains part of the troop.
The last gorilla birth at the zoo was Bella in 2015, the daughter of Kwan and the female Bahati.
The most recent breeding was initiated on the recommendation of the inter-zoo Species Survival Plan that manages the captive population of western lowland gorillas (a species whose Latin name, it must always be mentioned, is gorilla gorilla gorilla).
The mother is expected to keep child close for at least a couple of months, said Moyse, and visitors should be able to see the pair amid the troop when outdoor displays reopen to the public beginning at noon Wednesday.
The Lincoln Park Zoo’s Regenstein Center for African Apes will return to regular indoor hours for the public (10 a.m. to 5 p.m. daily) on May 18. Members-only sneak peeks are May 15-17; more information at www.lpzoo.org.
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