All in the (primate) family

Sid, a Mueller’s Bornean Gibbon also known as a gray gibbon, sits in his enclosure at the Idaho Falls Zoo on Sept. 7. Sid is one of 16 gray gibbons in the United States. Gray gibbons are indigenous to Borneo. John Roark /

Linda Beard, a zookeeper, feeds Sid, a gray gibbon, a grape at the Idaho Falls Zoo on Sept. 7. Sid is one of 16 gray gibbons in the United States. John Roark /

Zoo volunteer Robert Nitschke feeds a bottle to Sid, the baby gibbon, in this screen grab from an Idaho Falls Zoo YouTube video. Idaho Falls Zoo / YouTube

Retired Idaho National Laboratory physicist Robert Nitschke spent dozens of hours over the last several months raising a baby — holding it, feeding it and playing with it. Nitschke described the process as “live-moving.”

The infant was not a human child, but instead a creature very distantly related in the biological world: a Mueller Grey Gibbon.

The endangered primate was born June 16 at the Idaho Falls Zoo. Sid, now 2 months old, is among 16 grey gibbons in captivity in the U.S., according to zoo officials.

Sid has already faced plenty of challenges. The gibbon was born with sharp teeth, which is rare. That meant his mother wouldn’t nurse him. Zoo officials had to raise the animal and actively monitor him 24/7.

Staff have begun reintroducing Sid to his parents, a process that wouldn’t be possible without the zoo volunteers who were responsible for a large chunk of the 3,000-plus hours already spent caring for the animal.

“We generally never involve volunteers on even simple hand raising — and this was a very complicated one — but we had to because it was so time consuming,” zoo Operations Manager Linda Beard said. “And I think every single volunteer understood the uniqueness of it, and that it’s a lifetime experience.”

Sid’s husbandry needs differed considerably from conventional zoo animals, Beard said. Idaho Falls Zoo officials previously had hand raised a different species of gibbon. The keeper who assisted then had since moved on to a new zoo, but she was consulted after Sid’s birth.

In order to increase the likelihood that Sid’s first-time parents, 15 and 16 years old, respectively, would accept their offspring, Sid had to be raised on an accelerated schedule. The goal was to allow Sid to spend time in his parents’ enclosure by the four-month mark.

“The quicker we reintroduce him the smoother that would go,” Beard said. “In order to do that we had to push him past where he’d normally be at his age physically, and get him stronger than he would be at different milestones during the time.”

Twenty-nine zoo staff members and volunteers assisted in Sid’s upbringing. Shifts started at two hours each but were sometimes far longer, including one from midnight to 8 a.m. Because volunteers drifted in and out over the last several months, most were individually trained by zoo staff.

Adult volunteers usually assist with everyday animal care and the zoo’s educational exploration stations. To Nitschke, who has volunteered for seven years, raising the gibbon was a welcome opportunity. He usually volunteered two shifts per week.

“Sometimes the mission of the zoo manifests itself greatly, other times not so much,” he said. “If you’re just cleaning up after the camel sometimes you can forget how much that matters, but with the gibbon you can see it directly, especially with the limited number of critters out there.”

Volunteers started with simple exercises involving a vest covered in fleece string. Sid learned to hang on to the vest while he was fed from a bottle or slept.

As he got stronger, zoo staff and volunteers taught Sid to navigate and climb. He was taught to grab different materials, including rope or PVC.

A jungle gym complete with colorful blankets, rods and grates was set up in a large plastic tub. He later graduated to a full enclosure containing ropes and wooden dowels to navigate.

Over time, staff and volunteers developed an affinity for the animal.

“I don’t think they get any cuter than he does,” Beard said. “He’s like a normal playful infant: very silly, outgoing, sleeps a lot. He also plays and plays.”

Sid came to accept his temporary caregivers as well. He was reluctant to separate from his human handlers when zoo officials started to reintroduce him into his parents’ enclosure.

“We had to transition him away from being so attached to us,” Beard said. “But the gibbon parents had never been parents, so they didn’t know how to handle him. His mom was extremely grabby originally, so we had to teach her how to touch nice.”

Sid’s enclosure shares a wall with his parents’ pen so all three animals can become comfortable with each other without being in the same space.

Beard hopes Sid will be able to stay in his parents’ enclosure full time within the next month or two. Eventually, he will transition to a public exhibit where others can experience what volunteers are already very familiar with.

“He’s a great little critter,” Nitschke said. “And it was very rewarding raising him. One of the joys of being involved with the zoo is getting these rare opportunities.”

Reporter Kevin Trevellyan can be reached at 208-542-6762.