Queen emerges after brutal baboon war at Toronto Zoo

• A brutal battle for the throne of a baboon troop at the Toronto Zoo that erupted when the matriarch died became so vicious that staff intervened with hormone treatments to take “a little bit of an edge off ” the fighting females.

Medical records show that while the intervention last March helped reduce the number of vicious attacks and resulting injuries, it also helped an unlikely female to emerge as queen in the baboons’ game of thrones.

The fighting began shortly after the troop’s leader, 16- year- old Betty, was euthanized. Baboon troops are run by females, and their behaviour dictates that the matriarch’s oldest daughter become queen.

But zoo staff have said Betty’s oldest daughter, Molly, was too young to assert her dominance when her mother died in December 2014.

Putsie, the troop’s eldest female, saw an opportunity to grab the throne with support from her three daughters: Kate, Kristina and Kalamata.

Kalamata, who was at the bottom of the hierarchy one year ago, now wears the crown with her mother’s blessing, said Maria Franke, t he curator of t he zoo’s mammals.

Molly and her sister, Susan, became the victims of much of the fighting, which left them with numerous deep lacerations near their eyes and tails.

The fighting, which culminated in March last year, according to medical records obtained through freedom of information legislation, left Molly’s tail so damaged part of it had to be amputated. It also led to dozens of injuries among the other females of the 12- member troop, some that required surgery.

But Molly and Susan fought back, zoo staff said, targeting Kate, Kristina and Kalamata.

The factions were clear: Putsie, Kalamata, Kate and Kristina on one side and Molly and Susan on the other.

“Molly didn’t have the backing,” Franke said. In total, Molly’s been injured at least 17 times over the past two years, the records show.

On March 2, 2016, a keeper noticed “a large fresh wound” on her tail, according to the medical records. The next day, “Molly is holding her tail in her hands.”

On March 8 — Molly’s seventh birthday — zoo staff found tendons and muscles in her tail were exposed, so they decided to amputate six centimetres, according to Chris Dutton, the zoo’s senior veterinarian.

The next day, a recovering Molly, described as one of the youngest and “largest” females in the group, had some help from the zoo’s oldest male, Bwana Joe, records show. “The dominant male appears to protect her since the surgery,” the records state.

Kate and Kalamata didn’t fare much better.

Kalamata had much of her hair ripped out in 2015 as she suffered injuries from multiple attacks. The attacks continued in early 2016, which led to a “deep wound along her upper left eyelid” that was partially closed, and a cut along her right shoulder.

After 14 months of bloody fighting, zoo staff decided to give hormonal contraception to all of the females on March 14, 2016.

Staff surgically implanted devices that suppress estrus and the hormonal surges that go with it.

“We’ve used it to regulate the females so that there’s not this angst in the group, but it takes a little bit of an edge off,” said Franke.

Dutton and Franke said the fighting has diminished significantly since the hormonal interventions. “I think how we moved f orward dealing with the situation just goes to show it helped,” Franke said.

Medical records also indicate far fewer injuries since the females began contraception — there is no chance for reproduction as all the males are neutered.

Still, there are some fights — and Molly is taking the brunt of it. She suffered at least two tail injuries in July and August — one a deep wound. The keepers also found a deep cut over her left eye and a smaller one over her right. The swelling was so bad it pushed the eyeball deeper into the socket, according to the medical records.

She now spends much of her time with her sister, Susan.

Both Kate and Kristina have suffered a few injuries since the hormone intervention, but not Kalamata. Through the past year, she has begun hanging out with the troop’s males, who generally stay to themselves and away from the fighting, Franke said — a clear sign Kalamata is on the throne.