On paper, they seemed like a perfect match.
Baha, the Sacramento Zoo’s prized endangered Sumatran tiger, had successfully raised five cubs in captivity. Mohan, a majestic, younger male, had lived peacefully with female members of his species at a zoo in Memphis.
According to a list maintained by scientists who monitor tiger reproduction for the Association of Zoos and Aquariums and its Species Survival Plan, Baha and Mohan were genetically among the top five most valuable Sumatrans among 74 living in zoos in North America.
But a lengthy, carefully orchestrated plan to breed the pair went horribly awry this week when Mohan killed his potential mate just minutes after they came together, for the first time, in an enclosure in Sacramento. With a quickness and ferocity that left staffers virtually helpless, Mohan fatally attacked Baha, apparently crushing her larynx and cutting off her breathing.
The death has devastated the zoo’s staff and raised questions about the risks and potential rewards of breeding wild animals in captivity.
“It’s pretty horrible,” zoo director Kyle Burks said on Friday, two days after Baha’s death. “We love what we do, and we believe in it. But we lost part of our family, and it’s very, very hard. It breaks our hearts.”
Others argue that captive breeding enterprises are morally wrong, and are ripe for disaster.
“If I were running the world, I would stop breeding animals in captivity,” said Ed Stewart, founder and operator of the Performing Animal Welfare Society in Northern California, a sanctuary for elephants, tigers and other creatures relocated from zoos and breeders or retired from the entertainment industry.
“Yes, zoos have a conservation mission, and they do it with some science behind it,” he said. “I just hate to see animals in cages. It’s not natural. It’s not a shock, really, when tragedies like this happen.”
AZA spokesman Rob Vernon said statistics are not kept on the violent deaths of animals in captivity, but they occur rarely. At the Sacramento Zoo, two other big cats have been killed by their exhibit mates since 2005, officials said. The cats – a lion and a snow leopard – both had been on exhibit with their mates many months before they were attacked.
Since the early 1980s, the local zoo has taken part in the Species Survival Plan, an organized effort to manage selected species at zoos accredited by the AZA. The idea is to help ensure the survival of animals that are threatened or endangered in the wild. The zoo has introduced 18 big cats over the years, and Baha’s was the only immediate fatality, said Burks.
Sumatran tigers, which inhabit the Indonesian island of Sumatra, are critically endangered, said John Goodrich, senior director of the Panthera Tiger Program, an international conservation group devoted to saving large cats and their habitats. Mainly because of poaching, Goodrich and others said, only 400 to 600 Sumatran tigers are believed to exist in the wild.
Managing tigers and other species in captivity sometimes involves moving animals from one place to another based on breeding potential, Vernon said. Baha had been alone since her mate, Castro, died in 2014. Baha was 15 years old but was still considered young and healthy enough to breed, specialists said. Mohan is 11.
Based on genetics, behavioral observations of the two tigers and the Sacramento Zoo’s past success with Sumatrans, AZA specialists recommended bringing Baha and Mohan together in an attempt at breeding, said Karen Goodrowe Beck of the Point Defiance Zoo & Aquarium in Tacoma, Wash. Goodrowe Beck serves as the AZA’s Species Survival coordinator for Sumatran tigers. “They seemed like a good pair,” she said of the big cats.
Mohan moved to Sacramento in November, and at first lived under quarantine to allow staff to monitor his health and habits, said Burks. Mohan, whom keepers came to know for his “chuffs,” or puffing sounds, seemed to be adjusting fine. He and Baha, a favorite of zoo patrons because of her lack of shyness and her frequent eye contact with human visitors, rotated stints on exhibit. That way, they could gradually get used to each other’s scents.
In December, the zoo moved the tigers to a facility where they remained separated but could interact through wire mesh. “They could see each other, smell each other, rub against the mesh,” Burks said. “Every single thing we saw was good, positive interaction.”
Recent tests showed Baha was reproductively ready to mate. On Wednesday, the staff prepared for the pair’s first moments together.
At around 7 a.m., the cats separately got an early, meat-based breakfast. About an hour later, before the zoo’s 9 a.m. opening, seven trained staffers led by animal collections director Matt McKim gathered 10 feet to 20 feet in front of the tiger exhibit to observe the meeting.
Just in case it did not go well, McKim had a fire hose at the ready. Others carried fire extinguishers, flares, a pistol that shot blanks, shovels for banging. Veterinarians were on alert, preparing tranquilizer equipment.
Because Baha, at 181 pounds, was smaller than the 234-pound Mohan, she was placed first into the exhibit. “We wanted to put her in a position where she had an advantage,” Burks said. “We waited until she was facing the door, so there would be no surprise. They instantly saw each other.”
In the first moments of his arrival, Mohan crouched and chuffed, Burks and McKim recalled. The two tigers sniffed each other. Baha lightly touched a paw to Mohan’s face. Then, suddenly, the cats were rolling and running. Mohan lurched. “Very quickly he had an advantage,” Burks said.
“Break them up! Intervene!” McKim remembered shouting. He deployed the fire hose, and the others their weapons. A veterinarian rushed to the scene with a tranquilizer gun. But it was too late. Baha was gravely injured.
Mohan ran inside to the exhibit’s sleeping quarters. Once the staff secured him, the vet rushed to Baha’s side. She was loaded into a van and taken to the zoo’s hospital on the campus of the Land Park institution. But she could not be saved.
In the days since her death, the zoo has received an outpouring of grief and support via email, telephone and social media, said McKim and Burks.
Mohan is off exhibit while the zoo conducts an internal investigation into what, if anything, could have prevented the fatal attack. Euthanasia is not being considered, said Goodrowe Beck, but Mohan might be transferred to another facility. “His value for reproduction purposes will not change,” Goodrowe Beck said. “But how he is managed will.”
The zoo is unlikely to face any penalties, nor will its status with the Species Survival Plan be affected, she said. “We would still welcome them as participants.”
Stewart, of PAWS, pressed for a shift in emphasis from the breeding of captive tigers and other animals to protecting their natural habitats. He said captive breeding programs rarely end up releasing tigers and other creatures back into the wild, where their habitats are disappearing. “If that’s the case,” he asked, “What’s the point?”
Because of the prevalence of poaching, the AZA has no immediate plan to release Sumatran tigers through the Species Survival Plan, said Goodrowe Beck. “It’s just not feasible now,” she said. “But we hope in the future to be able to do so.”
Goodrich of Panthera said captive breeding programs should be viewed as a “last resort,” a final line of defense against the complete destruction of a species.
Working with exotic animals is tricky and unpredictable, he said, whether they are in the wild or in captivity.
“The first lesson here is that things happen,” said Goodrich. “These are wild animals. We don’t understand them as well as we would like to. Despite our very best efforts, bad things do happen.”