In a heartbreaking post on Thursday, the Toronto Zoo announced that one of the red panda cubs born at the zoo in June has died. 

"As we've shared with our Zoo community, the first few months of red panda cubs' lives are a critical period, which highlights how fragile this species is whether under human care or in the wild," the post reads. 

The journey first began when Sakura, a geriatric 10-year-old female arrived at the Toronto Zoo earlier this year. Although Sakura was past a typical breeding age, staff confirmed that she had arrived in Toronto pregnant. 

Shortly after, the cubs' mother began experiencing significant health issues, which were not unusual for a geriatric red panda. Sakura started showing behaviours suggestive of abnormal neurological activities, and a precautionary decision was made to begin supplemental feedings for the cubs earlier this week. 

According to the Toronto Zoo's post, red pandas have low rates of offspring survival both in the wild and in human care, and recent studies show that as few as 40 per cent of cubs reach their first birthday. 

Staff say Sakura's condition recently worsened, so their vet team had been providing medical care with the goal of having her healthy enough to continue raising her cubs until they could thrive independently. 

The two red panda cubs. Photo: Toronto Zoo.

On Wednesday, the smaller of the two red panda cubs was brought to the zoo's Wildlife Health Centre after staff observed that he was not drinking well, had a reduced appetite, and felt cold to the touch. 

Despite all efforts, including moving the cub to an incubator in the intensive care unit, he passed away just shy of being six weeks old. 

A gross post-mortem examination revealed that the cub had no fat reserve. 

"As the 'runt' of the two cubs, he was already at a disadvantage when facing the recent reduced milk production from his mom. The larger female cub has much better fat reserves which has helped her through this short period of caloric deficit," the Zoo said in a statement. 

"There were also signs of aspiration affecting his lungs which is not uncommon when syringe supplementing newborns and this becomes increasingly more likely when they are also weak." 

Along with this, the little one had two intussusceptions in his intestines, which means that one section of his intestine was sliding into the adjacent portion, which obstructed or decreased the passage of food. 

"While this outcome is not unexpected given their high mortality rate in their first year, we are truly saddened by this loss. The Zoo team is focused on the remaining female cub that currently appears healthy, but it will be some time before her future is secure," the statement continues. 

"We also continue to closely monitor Sakura, as she is no longer nursing her remaining cub but is cleaning and caring for her in other ways. Sakura is currently stable and receiving medical treatment and we are balancing the risk of separating her from the remaining cub against the need to understand fully the cause of her seizures which is why we have opted to have them remain together during this time." 

Sakura and the remaining female cub will not be visible in the red panda habitat at the zoo. 

Last week, a two-year-old Masai giraffe named Matumaini (also known as Matu) died during a planned castration procedure at the zoo. 

The Toronto Zoo killed a baby giraffe after castration attempt gone wrong. After putting it under and attempting the procedure the poor 2 year old baby giraffe aspirated and died. 😢 @peta 🦒🦒🦒

— Theresa Longo Fans (@BarkJack_) July 27, 2024

A preliminary pathology report found that the animal died due to "regurgitated and inhaled ruminal content." Matu was undergoing a castration procedure last Thursday when he stopped breathing.