Zookeepers found her on the ground and unresponsive Tuesday and pronounced her dead. Veterinarians said she had passed her daily and bi-weekly health checks.
"M'Dunda has been part of our Oakland Zoo family for 26 years. She was such a gentle being, and closely bonded with her keepers. We'll miss her greatly," said Dr. Joel Parrott, President & CEO of Oakland Zoo.
The 50-year-old was the eldest in the Oakland Zoo's African elephant herd, officials said in a statement.
These African Elephants at the Oakland Zoo seem to be in mourning following the death of Grand Old Lady M’Dunda at age 50. pic.twitter.com/IAK7xmKaIr— Eric Thomas (@ericthomaskgo) December 4, 2019
"She's the oldest of the four and she was actually the sweetest of the elephants too. She had a great disposition and was just gentle around her handlers," the zoo said.
It appears the other elephants are taking the loss pretty hard.
"We're not experts on elephant body language, but it sure looks like these residents of the Oakland Zoo have lost their best friend," the zoo said.
The zoo shared video and photos of M'Dunda who recently celebrated her 50th birthday this past September with her favorite treats.
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M'Dunda was the third oldest African elephant in an AZA (Association of Zoos and Aquariums) zoo, according to officials.
"M'Dunda came to Oakland Zoo in 1993 from San Diego Zoo, and quickly built a reputation of having a very gentle and kind demeanor. She rumbled to communicate with her herd mates and keepers, and was often observed trunk twirling with Osh, the male of the herd," said the zoo.
"She was just a great elephant. She's going to be missed by our whole staff."
She was taken to UC Davis School of Veterinary Medicine for a necropsy and testing to determine the specific cause of death.
"She was real healthy. She was even healthy at the end. She wasn't sick," officials said.
But at her advanced age, there's a long list of ailments that could be instantly fatal, including heart attack.
The death of M'Dunda now leaves the Oakland Zoo with just three African Elephants - females Donna and Lisa and male Osh.