September 24 is celebrated annually as World Gorilla Day. This year, we also celebrate the 35th anniversary of Oracle’s support of the Dian Fossey Gorilla Fund. In commemoration, we’d like to introduce you to Nzeli, a remarkable female mountain gorilla whose life has spanned those same years.
But first things first.
In 1967, Dian Fossey established the Karisoke Research Center in Rwanda, pioneering long-term daily monitoring of wild gorillas. It would become the basecamp for what is now the Dian Fossey Gorilla Fund, founded by Fossey in 1977 as the Digit Fund, after her favorite gorilla “Digit” was killed by poachers. By then, Karisoke staff were already deterring poachers, cutting snares, and observing, documenting, and studying each day of gorilla life to help ensure the species’ survival.
Nzeli arrives with Oracle close behind
In 1985, Nzeli—whose name means “September” in the Kinyarwanda language spoken in Rwanda—was born into the Susa group in the high-altitude forests of the Virunga mountains. Her arrival was both ordinary and extraordinary. Ordinary because, like any gorilla infant, she was cradled against her mother’s chest and protected by the circle of her group. Extraordinary because, while there were fewer than 250 mountain gorillas in the Virungas at the time of her birth, she would live to see that number grow to over 600 in the Virungas, and more than 1,000 in all, largely as a result of the Dian Fossey Gorilla Fund’s conservation efforts and the support of long-term donors like Oracle. Nzeli would prove to be a model of resiliency and adaptability. At nearly 40 years of age, she gave birth to her seventh baby in June of 2025; if that infant survives and thrives, mother and child will have made history.
By 1989, when Oracle began funding the organization, Nzeli was a sturdy youngster. Oracle was the first major U.S. company to take a leading role in protecting mountain gorillas, providing resources to expand and sustain anti-poaching patrols, study gorillas and their habitat, and build local capacity for conservation. Over the last 35 years, this partnership has flourished, and so has Nzeli—teaching us what’s possible when we continuously invest in conservation.
Almost all female gorillas emigrate from their natal group once they reach the age of sexual maturity to avoid inbreeding with males of their own family. Nzeli was no different, but she did do something unusual: she moved from one group to another—a total of eleven times—setting a record for highest number of transfers.
Intrepid, adaptable Nzeli and her data story
While we can’t know for certain why Nzeli transferred so many times, the answers we do have come from data. For decades, Fossey Fund trackers and scientists—who are in the field 365 days a year—filled notebooks with observations about Nzeli’s movements, health, and behaviors, the shifting dynamics of her groups, and the lives of her seven children. In 2013, with Oracle’s support, those handwritten pages were transformed into a digital archive hosted in the Oracle Cloud for free. In 2016, a field data-collection app—designed and developed by the Fossey Fund with a grant from Oracle—replaced paper altogether, allowing every observation to be digitally recorded in real time, and securely stored. Today, the Fossey Fund uses Oracle Analytics Cloud to glean insights from its data. So, what do we know?
We know, for example, that the three oldest female mountain gorillas monitored by the Fossey Fund—Mudakama, Nzeli, and Gutangara, who as of this writing are 38, 40, and 41 years old—share a common past. They were all born and raised in the large Susa group, and in April 1995 they all moved together to the historic Pablo group, where they spent most of their reproductive years.
“Now, 30 years have passed since that bold move, and their paths have diverged. Gutangara lives in a group that split off from Pablo’s group, while Nzeli and Mudakama are together again after years apart, living in the Mutobo group which is—interestingly—led by the son of Gutangara,” writes Veronica Vecellio, Senior Advisor of the Fossey Fund’s gorilla program.
We know females may change groups multiple times in the course of their lives, sea
rching for just the right fit, or the right silverback, along with reproductive partners who will provide stability and protection for themselves and their offspring. We also know that female mountain gorillas seek out familiar female faces when deciding whether to move from one social group to another—often transferring when they recognize old friends they grew up with or lived with at some point.
“Nzeli holds the record for the highest number of group transfers. Over her lifetime, she has moved between 11 different groups, spending the most time in the Pablo group, where she stayed for 12 years. Then, after leaving, she changed groups nine more times before settling in Mutobo’s group in March 2024, where she reunited with her old companion Mudakama,” Vecellio explains.
“As a result of all this moving around, Nzeli’s offspring are now scattered across different groups, including two in Segasira’s group, while her youngest remains in Kureba’s group with his father, Ishavu,” says Vecellio. “Nzeli’s resilience and remarkable adaptability make her a fascinating character among the gorillas we study.”
Nzeli endures as a living legacy
The partnership between Oracle and the Dian Fossey Gorilla Fund means Nzeli’s life story is now part of a searchable database used by scientists across continents. Decades’ worth of data provides young scientists entering the field in Rwanda with a literal curriculum vitae of Nzeli’s bold moves, close bonds, hard knocks, and successful tactics. But her story doesn’t end in the forest; it helps to shape conservation strategies, land use decisions, and government policies that aim to protect gorillas for generations to come.
Today, Nzeli stands as one of the most remarkable elders of her species. Born when the odds were against her survival, she has not only survived, but thrived and contributed to mountain gorillas’ comeback—with help from her friends at the Fossey Fund and Oracle, and from people like you who choose to donate.
On World Gorilla Day 2025, Oracle celebrates Nzeli and the legacy of Dian Fossey, who understood that by protecting one life, one forest, one dataset at a time, we can improve the prospects of an entire species.
