Another animal has died at The Dallas Zoo, the fifth one in 2021. This time, it was a 14-year-old giraffe named Jesse who died on October 29.

The zoo said it was unable to identify the cause of death.

This marks the third giraffe to die at the Dallas Zoo in one month.

In early October, the zoo euthanized Marekani, a baby giraffe who sustained injuries the zoo said it could not fix.

On October 25, the zoo divulged the death of 19-year-old giraffe Auggie, which they attributed to "age-related health issues that led to liver failure."

According to the zoo, Jesse died "after less than a week of fighting with symptoms and rapid deterioration," which it said "exactly reflected" the symptoms that Auggie suffered.

But if Auggie's death was age-related, and Jesse was 14, that seems like it would not be the same cause of death? Either that or Auggie's death was not "age-related" as they claimed.

The zoo said it was calling in outside experts to investigate possible causes.

"We are awaiting final necropsy findings and significant additional lab work for both Jesse and Auggie to help us determine what we are dealing with so we know how to address the issue," the zoo said.

More details are expected in the coming week. UPDATE 11-1-2021: According to a Facebook post, necropsy results showed that both giraffes suffered liver damage, and the zoo is now theorizing that they were exposed to a toxin, either through a food source, in the exhibit, or introduced via a foreign object. They're also testing for Zoonotic diseases, including encephalomyocarditis.

The claim to fame for Jesse (also spelled "Jessie" on the zoo's website) is that, at 17 feet tall, he was their tallest giraffe.

These other animals have died at the Dallas Zoo:

• Auggie, a 19-year-old giraffe, died of liver failure on either October 23 or 24.
• Marekani, a 3-month-old baby giraffe, sustained a mysterious injury and was euthanized on October 3, 2021.
• Kirk, a 31-year-old chimpanzee, died in August 2021 due to "surprise" heart disease.
• Keeya, a 6-year-old Hartmann's mountain zebra, died in March 2021 due to a mysterious unexplained head injury.
• Subira, a 24-year-old silverback gorilla, died suddenly in March 2020, due to a cough, or maybe cardiovascular disease.
• Hope, a 23-year-old Western lowland gorilla, died suddenly in November 2019 after being at the zoo for only two years.
• Ola, an 8-year-old female African painted dog, was killed in July 2019 by two other painted dogs, less than a month after she was transferred to the zoo.
• Witten, a 1-year-old giraffe, died in June 2019 during a physical exam under anesthesia when he suddenly stopped breathing.
• Adhama, a baby hippopotamus, mysteriously died in 2018.
• Kipenzi, a baby giraffe, died in 2015 after running in her enclosure.
• Kamau, a young cheetah, died of pneumonia in 2014.
• Johari, a female lion, was killed in front of zoo spectators in 2013 by male lions with whom she shared an enclosure.

The zoo has also lost animals: In February they lost a crow called Onyx who was part of their so-called animal ambassador team, participating in a training session for a bird show. He was never found.