Nyack, the Lion of the Indianapolis Zoo, is killed by the mother of her cubs in an "unprovoked" attack

When they arrived, they discovered a primal scene.

Nyack was fighting a fierce battle with Zuri, a 12-year-old lioness and mother of her children – and he was losing.

"She had Nyack by the neck," zoo curator David Hagan told Reuters about the October 15 attack. Attempts were made to separate the couple, but Zuri held out until Nyack stopped moving, Hagan said. Necropsy revealed that the lion died of suffocation following neck wounds, the Indianapolis Star reported.

This sudden attack, which took place before the zoo was open to the public, left the lion staff and experts completely confused: why would a lioness attack a male with whom she was familiar but who also spawned his little ones?

A precise reason may never be known, but Craig Packer, senior researcher at the University of Minnesota's Lions Center, told The Washington Post that Nyack's death may be related to his "unusual relationship" with Zuri. .

"She apparently dominated it all the time they were together," said Packer, who has studied the lions extensively in the Serengeti. "That in itself is almost unknown."

He added, "I have never heard of a woman as dominant as a man."

For eight years, Nyack and Zuri coexisted without incident and had "done very well together," Hagan told WIBC. "We do not know what was the precursor of the fight," he said.

In a Facebook message announcing Nyack's death on Friday, the zoo announced that he would conduct a "thorough review to try to understand what might have led to it." Zuri and his three little ones, one of whom was present during the deadly clash, are all fine, says the post.

Zuri will stay at the zoo, reported WIBC. According to Reuters, there is no plan to change the way lions are managed.

Part of the zoo's effort to understand what happened was to call Packer, who described the attack as "surprising" and "so unexpected."

"They called me because they were perplexed, and I agree that it's amazing," Packer said. He added about the attack: "It was totally flawless and it was certainly not typical."

Nyack's murder by Zuri is bizarre for two reasons, said Packer: He was the father of his little ones and she had engaged him face to face.

Although the details of the incident are shocking, the female lions attacking men are not unprecedented. In September, a video showed a group of lionesses attacking a male lion at the West Midland Safari Park in England, the BBC reported. This lion, who survived, was presented with pride only last year, according to the BBC.

In nature, said Packer, he also observed females attacking a nomadic male, but only for the purpose of hunting the "weird" lion and protecting their cubs. They might try to hurt the male, but the intention is not to kill, he said.

Sukari, the 3 year old daughter of the lions, was in the enclosure during the attack. Zuri is described as an "attentive and protective mother" who usually looks after her cubs, according to the zoo. But Packer said Sukari did not seem "threatened with anything".

The incident, said Packer, could come from the "unusual combination" of a "gentle man" and an "all-powerful woman".

"I do not usually associate this kind of personality with a lioness," he said. "The fact that it has developed is fascinating."

Nyack has been described by the zoo as "laid back". Zuri, on the other hand, was "big and very dominant," said Packer. According to the zoo, Zuri weighed only 25 pounds less than Nyack.

Male lions are usually much bigger than females and more aggressive, and "being next to a big male, it's like living next to a barrel of dynamite," Packer said. .

"Women will sometimes be annoyed by men and will hit them, but they are very careful not to provoke them too much," he said.

That does not seem to be the dynamic between Nyack and Zuri. Given Nyack's kindness, Packer stated that it was likely that Zuri would not receive the "habitual repression of the male that would be normal in this species", which allowed him to exercise dominance over him.

"Apparently, the male was still very subordinate to him, which is totally strange," said Packer.

In last week's brutal fight, Packer said Zuri had attacked Nyack twice. The first time, Nyack managed to escape, but Zuri followed him, he said.

"This is the second time she has taken it, she seems to have a sore throat," he said.

Nyack's death left the zoo's staff devastated, Hagan told Reuters. On social media, many who visited Nyack shared photos and paid tribute to him.

"My heart is broken," wrote one person on Facebook. "It was the best part of the zoo."

Another user mentioned going to the zoo early in the morning, just to hear the roar of Nyack.

One person shared a picture of Nyack "calmly" leaning against the window of his enclosure a few days before his death. Zuri was lying a few steps away and "everything seemed fine," the person wrote.

Packer said the reasons Zuri only recently attacked remain a mystery, adding that animals are "very unpredictable".

"The woman seemed to have a bad day," he said.