Rani, a female Asian elephant at the St. Louis Zoo, unexpectedly died after a dog running loose agitated her herd, zoo officials said.
The 27-year-old mother of three died a week ago.
"We are absolutely devastated. We ask for the community's thoughts and support during this difficult time," said Michael Macek, the zoo's director, in a news release on Tuesday. "Our team of professional animal care experts did everything possible, but we couldn't save Rani."
On the afternoon of Oct.13, a small dog wandered into the zoo and made its way near the elephant habitat, according to the zoo. The elephant care team worked to capture the dog, but its presence caused an elephant that was outside the barn to become agitated.
Rani was indoors eating dinner at the time, and never saw the dog.
But the elephant care members "observed Rani become agitated in reaction to the vocalizations from the herd. They saw Rani circle and vocalize, all within a very brief period, before collapsing."
A necropsy found preexisting changes in the elephant's heart. It was unknown whether the changes were a factor in her death, the zoo news release read, and further testing is being done.
The dog has been handed over to a shelter, according to the zoo. It wasn't immediately clear how the dog got into the zoo.
Rani and her mother Ellie came to the zoo in 2001, upon recommendation by the Association of Zoos & Aquariums Asian Elephant Species Survival Plan, which aims to manage North America's Asian elephant population and maximize their health and genetic diversity, the zoo said.
Ellie, 52, still lives at the zoo, among seven other elephants in a three-generation family.
"Rani was a special member of this elephant family group," said Katie Pilgram-Kloppe, who manages the zoo's River's Edge area where the elephants live. Rani loved playing with her sisters, she added, and was known for making "a unique squeaking noise that her daughter Jade also mimics."
The rest of the herd calmed down quickly and are doing well, the zoo said.
The population of wild Asian elephants is fewer than 50,000, according to the World Wildlife Fund. Habitat loss and poaching are the greatest threats to the endangered species.
