TORONTO - On a hot Thursday last September, workers at the Toronto Zoo were making a racket as they unloaded barriers to set up a finish line for the Oasis ZooRun, a race that sees thousands of participants make their way past animal exhibits at the sprawling facility.
The noise was agitating the beleaguered baboon troop nearby, riling up already high-strung members of the group.
It took nearly 45 minutes that night for the olive baboons to leave the outdoor area of their exhibit and mosey into the house where they sleep, according to medical records obtained by The Canadian Press. It was the same story the following night, with staff citing the race set-up and hot weather as potential reasons for the uneasy behaviour, documents show.
The tensions around the time of the race were just one example of the issues the zoo has to deal with when it comes to managing the baboon group plagued by vicious in-fighting for the past three years.
There have been battle wounds that required surgery, hormone therapy to control unruly females, and ongoing enhancements to the enclosure, all in an attempt to keep the group stable and help some members survive each other.
The baboons' captivity, records and experts suggest, has exacerbated problems that might dissipate in the wild.
"Baboons are naturally suspicious and wary of weird things," said Brent Huffman, one of the troop's keepers, who notes that the animals' combative nature goes into overdrive if weather or other factors keep them cooped up indoors.
"It's almost like cabin fever. It increases the social tensions."
In October, not too long after the race, the baboons refused to enter their indoor enclosure for the better part of a week, Huffman said. It turned out construction material was lodged on top of the chain-link roof of their private yard, so the group stayed outside and away from the noise caused by the rattling debris, he said.
Such external factors are compounded by the fighting that has rocked the troop as the females battle for supremacy.
Currently, Molly, whose dead mother used to be the baboon queen, languishes at the bottom of the troop's hierarchy. The rightful heir is fat, permanently disfigured with a weepy eye and a surgically shortened tail — and has even been attacked by her own sister, Susan. Molly has been injured at least 25 times over the past three years, according to medical records.
In the wild, Molly and Susan might mate and grow their family, biding their time before taking another run at the crown when their family's numbers increase. But that won't happen at the Toronto Zoo because the baboon males, who are either their brothers, half brothers or their father, cannot reproduce due to sterilization.
The troop is currently ruled by Kalamata, who emerged as queen in the baboons' own game of thrones in 2016, shortly after the zoo decided to intervene with hormone implants to curtail the animals' violent behaviour. Once the doormat, she had a meteoric rise with the backing of her aging mother, Putsie, and her sisters Kristina and Kate.
Kalamata is now the first to eat grapes, bananas and zucchini, a sure sign of her dominance, staff say.
The troop's delicate hierarchy, however, necessitates frequent intervention by staff.
The baboons' indoor enclosure has been modified to build more escape routes for when fights break out. The group's private outdoor space will be upgraded this summer with a roof, windscreen and heaters so baboons can go out during cold stretches. And hormone therapy is still being used to manage the most volatile behaviour.
The group's "three Ks", Kalamata, Kristina and Kate, had deslorelin — contraception that also has a calming effect — surgically implanted in November after staff discovered all three had begun cycling — or were in heat — as evidenced by their swollen posteriors and attention from the males, said Chris Dutton, the zoo's head of veterinary services.
Despite the therapy, however, battles erupted again in December, records show. That fighting was due to the baboons being locked indoors for an extended period during a cold snap — and also due to Molly and Susan cycling again. They were given new hormone therapy in January.
"With their restricted space, the olive baboons are fighting more," reads a note in Molly's records. "Clumps of hair missing on several, bite wounds on Molly."
Huffman noted, however, that the zoo's interventions have helped.
"With the hormonal treatments, the baboons have figured out their hierarchy and we're trying to help them maintain that," he said.
Urs Kalbitzer, a primatologist and post-doctoral fellow in the anthropology department at McGill University, called the troop's behaviour "fascinating" and in many ways the opposite of what he observed over nine months in Botswana watching chacma baboons, primates similar in behaviour and hierarchical structure to olive baboons.
"I think it's a really good approach (zoo staff) are taking by initially letting them fight it out, but also to protect them when the fighting became problematic," Kalbitzer said.
In the wild, vicious fighting occurs almost always among the males, he said. At the zoo, the males have stayed out of the fighting — their medical records are in many cases blank, save for the alpha male, Bwana Joe, who at 22 is the troop's elder, and on joint and arthritis medication.
Fighting among wild female baboons would generally occur between members of a family higher on the ladder with those lower down, Kalbitzer said, and injuries are never that serious.
Prolonged fighting and instability among females in the wild could lead to the troop splitting, a rare occurrence he said, but one Kalbitzer observed among the baboons in Botswana. That came about because of food scarcity.
"One solution for prolonged problems like this is that the group splits into two groups to avoid these conflicts," he said. "Which is not possible in the zoo."
For the Toronto baboons, staff will keep watching, waiting and hoping. Watching the baboons' rear ends for signs of cycling, waiting for more fights and hoping the females are happy with their lot in life.