As her caretakers approached her habitat on a recent morning at the Dallas Zoo, 3-month-old Sumini perked up from her nap, ready to show off for her visitors.
The Sumatran tiger cub ran to greet them, jumping into leaf piles and doing somersaults in the hay to ensure she was the center of attention. Her paws — a little too big for the rest of her body, foreshadowing a growth spurt — slapped the ground as she played.
“There she goes, ‘Zoomie Sumi,’” said Lisa Van Slett, associate curator of mammals at the zoo, using a nickname that staff gave the cub because of her boisterous behavior.
A group of children leaned over the ledge of the exhibit, across from the gibbons in the Primate Place, to get a better view, squealing at the sight of the cub. At one point, Sumini chuffed happily, making a breathy noise similar in function to a house cat’s purr.
“I can say with certainty, cats are cats,” Van Slett said. “They like to do all the cute cat things.”
Sumini’s energetic, curious behavior around humans is partly indicative of her journey into the world. She is the first tiger cub to be born at the Dallas Zoo since 1948 and, after a few challenges, is well on her way to being in the public eye full time.
A hand-raised cub
Eight-year-old Sukacita gave birth to Sumini on Aug. 2. She had been recommended to breed with 10-year-old Kuasa by the Sumatran tiger species survival plan created through the Association of Zoos and Aquariums, the group that accredits the Dallas Zoo.
Even though the two were recommended to breed, introducing the strictly solitary animals had to be done carefully.
In the spring, caretakers began introducing the two behind the scenes through what’s known as a “howdy.” During a howdy, the tigers share a mesh wall and can see, smell and talk to each other. Caretakers watch for positive signs between the animals to tell when it’s time to breed.
“They should both be chuffing at one another, and they’ll kind of touch noses and smell, and they cheek rub,” Van Slett said. “The cheek rub will become like a body rub, and she’ll rub her whole body along the fence side, and she will roll on the ground which is another big sign. … His behavior is really important, too, so if he can’t see her, he’ll be calling desperately.”
Van Slett said the experience of welcoming three lion cubs last summer helped caretakers prepare for Sumini’s birth. Staff closely monitored Sukacita through cameras installed in the behind-the-scenes habitat, and Sumini was born about 100 days after the pair mated.
But there was one big problem: Sukacita didn’t show natural maternal instincts, and staff weren’t sure she was producing milk. Veterinarians, zoo management and experts with the species survival plan made the difficult decision to hand-rear the cub, meaning she would be fed entirely from a bottle.
The decision to hand-raise an animal presents some risks.
“For tigers, they can imprint on people pretty easily,” Van Slett said, referring to the condition where an animal is more comfortable with humans than its own species. “In AZA zoos it’s preferred to have them mom-raised because then as adults, they’re more likely to breed successfully.”
Sumini is growing out of some behaviors, but indications that she has imprinted on humans are still present.
“She’s definitely interested in people,” Van Slett said. “It used to be for a while she would call when we’d walked away. She likes it when people are present and looking at her.”
To help her stay associated with other tigers while she was being hand-raised, Sumini had a “tiger babysitter” each day, a lengthened form of a howdy.
“Even from the first day she was born, we would rotate which adult was in the room next to her so that she could always hear tigers, smell tigers and just kind of have them around her,” Van Slett said.
Passing the ‘swim test’
After about 11 weeks, Sumini was weaned off the bottle. Staff no longer spend much time in the habitat with her, and she’s now eating meat.
But easing away from bottle-feeding was only the first step in her journey to adulthood. On Nov. 17, the cub had to clear another hurdle: the swim test.
“They are natural swimmers and do have webbed feet, but they still need to learn,” Van Slett said.
While her habitat is a full acre complete with bamboo stalks, a swimming pool and plenty of logs to climb, Sumini is confined to about a 60-foot run against one wall of the exhibit. Affectionately referred to as the “baby-proofed” area, the run is surrounded by a 4-foot black fence and contains plenty of toys.
Ensuring that Sumini is a strong swimmer is a huge step toward removing that fence.
On the day of the test, Van Slett situated herself at the edge of the pool and tossed the cub in. Sumini landed with a splash and confidently paddled to shore.
“She was a natural,” Van Slett said. “She did perfectly. … We knew she was ready for it because we’ve seen her sometimes on her water bowl splish and splashing with her little paws playing with the water, so she was telling us it was time.”
Now, Sumini just has to get a little bigger before staff are ready to take down the baby gates.
At 3 months old, Sumini is about 2 feet long and a foot tall. Sumatran tigers are the smallest tiger subspecies; as an adult, Sumini will be about 5 feet long (not including her tail), 3 feet tall and 200 pounds.
Staff would like to see her gain at least 15 pounds before they feel comfortable letting her roam the full habitat.
“We’re just waiting for her to get bigger so that she’s not lost in the acre,” Van Slett said.
A monumental win for the species
When Sumini was born, the Dallas Zoo called it a “monumental win” for her species.
Sumatran tigers are critically endangered. There are only about 400 left in their natural habitat on the island of Sumatra, in western Indonesia.
While animals at the zoo are usually named for their personalities, Sumini is an exception.
“Sumini is the last name of a woman in Indonesia who founded and leads a team of all-female rangers out in the forest in Indonesia,” Van Slett said. “They go out there to check for snares and other poaching traps, and to generally protect the forest because there’s a lot of deforestation in that area. We thought that was a really good, strong female name for her.”
For now, Sumini is out in her run from 9 a.m. until around noon each day. Eventually she’ll spend the whole day in the entire habitat, and do daily rotations with the zoo’s five other Sumatran tigers.
Until she’s ready, staff will focus on helping her grow. They’ll also start training sessions, which Sumini will participate in for years to come, that are designed to make regular veterinary care go more smoothly.
“The actual training will be her whole life, we’ll continue to work on it,” Van Slett said. “As long as they’re getting those really positive rewards and favorite treats at the end, they’re pretty good at it.”
