A sudden loss is rocking the community at the Cherry Brook Zoo as Lexie, the zoo's snow leopard, died unexpectedly on Saturday.

The 16-year-old snow leopard was found by her keeper Saturday morning, and the zoo's vet later found she had died in her sleep.

"It's certainly upsetting and sad, and absolutely a shock … because we didn't see it coming," said Martha McDevitt, the zoo's executive director.

"She was absolutely fine, and herself behaviourally the day before. It was just so sudden. We're having a hard time reeling from that."

Lexie came into the Cherry Brook Zoo's care in 2006, after a transfer from the Assiniboine Zoo in Winnipeg. (Submitted by Martha McDevitt)

The cause of Lexie's death is still unknown. Her keepers say there were no clinical signs or sudden changes in her behaviour leading up to her death, and to top it off, she was very healthy.

McDevitt said that although Lexie wasn't young — snow leopards live between 15 and 18 years in the wild and a few more when in captivity — she was spry for her age, making her death even more of a puzzle.

Lexie's body had been sent to UPEI for a post-mortem. The zoo said preliminary tests have not come back with any answers, but the veterinary school will be performing more tests in the weeks to come.

Lexie, a snow leopard in Saint John, has died and people across the province are mourning, especially the Cherry Brook Zoo workers who spent time with her every day. 2:31

"It's hard because we want to have closure … and it's a mystery at this point, which is not helpful in the process of grieving," said McDevitt.

Part of the family

The Cherry Brook Zoo has had Lexie in its care since 2006, after she was transferred from the Assiniboine Park Zoo in Winnipeg.

"I was there the day she arrived, actually I was one of the people who carried her into her new home, and then I was one of the people who carried her out on the day she passed," said zookeeper Hugh O'Hara.

Cherry Brook Zoo executive director Martha McDevitt says Lexie's loss was 'unexpected,' as she was very healthy. (CBC)

"She was an elusive cat for all those years. And in the last few years, she's come around a lot … that makes it even harder now because she'd become so much more friendly with us, more trusting."

Another one of Lexie's keepers, Megan Gorey, said she still hasn't come to terms with her death.

"It's one of the hardest things I've ever had to go through, and every day not being able to work with her is going to be really hard moving forward," she said.

Over the years, zookeepers and staff worked with Lexie daily on things such as accepting medication, becoming comfortable in her environment, and trusting humans.

Gorey said that just in the past few years, since she started working at the zoo, she's seen a drastic change.

"We just had to find what made Lexie happy," she said.

Zoo-keeper Hugh O'hara says finding Lexie unresponsive in her enclosure Saturday morning was an 'emotional' moment. (Submitted by Martha McDevitt)

"It makes it a lot harder to have her gone so quickly, because we were making so much progress with her, and she had been really bonding with humans, and gaining that back," said McDevitt.

Fond memories

The leopard also touched many visitors and volunteers over her 14 years at the zoo.

Patrick Maloney, a regular visitor of the zoo, said he grew to love Lexie after an encounter back in 2007, on a first date with the woman who would become his wife.

He said it was rainy, and not many animals were out at the zoo, but when they got to Lexie's enclosure, she took immediate interest in the couple, and started following them back and forth.

The Cherry Brook Zoo has lost its beloved snow leopard, after she was found dead in her enclosure on Feb. 29. (CBC)

"When we moved, she moved, when we stopped, she stopped. It was a really sweet experience," he said.

Maloney said it's going to be "strange" not having Lexie at the zoo.

"Knowing that she's not just gone away for awhile, but that she will never be coming back, that'll be sad."

Taking it day by day

Visitors from across the province, and the country, have been posting pictures on the Cherry Brook Zoo's Facebook page of photos they've taken of Lexie, and sharing their stories and kind words.

McDevitt said the ongoing support has made the grieving a little bit easier.

"She was definitely a part of our family and our community … so it'll definitely be a loss," she said.

In the meantime, work continues as usual at the zoo, including caring for the rest of its big cats: two Siberian tigers and two African lions.

With the death of Cherry Brook Zoo's snow leopard, there are only a small handful of large cats left: two Siberian tigers and two African lions. (CBC)

While Gorey processes the pain of losing Lexie, she hopes to honour the leopard's legacy.

"We are going to continue to educate people, and tell people about why Lexie was here, and what the importance of these animals are," she said.