It’s rare to see a solitary male gorilla successfully – and rapidly – build his own thriving family. But 19-year-old silverback Mutobo is doing an excellent job at it, just five years after forming his group. He now leads 15 gorillas with impressive confidence, as the only adult male in the group. Female gorillas seem particularly attracted to him, with eight females joining from other groups, including three in recent months.
Mutobo left his natal group, called Pablo group, at the young age of 13, before he’d developed his full silverback size. He then lived alone for two years, while continuing to grow and mature into his current impressive size. In 2019, while interacting with a neighboring group, three females joined him, thus forming a new group. Since then, Mutobo has fathered six offspring and developed exceptional paternal skills. The infants enjoy spending time with him, which may make him even more attractive to females.
Strong family history
Growing up in a close-knit family, Mutobo benefited from strong family bonds created by his mother, Gutangara, who is a prolific matriarch. So his ability to create and maintain a strong family unit may be an inherited quality and certainly is a skill that contributes to his confidence and effective leadership.
Mutobo has formed strong bonds with the group’s six youngsters, who range in age from 1 month to 4 years old. He shares a particularly special connection with 2-year-old Intatezuka, whom we’ve nicknamed “Zuk.” She often plays with Mutobo or rides comfortably on his back. She even frequently leaves her mother’s care to spend the day close to her father.
During several weeks in early 2024, three females from a neighboring group joined Mutobo, one at a time. These moves were unusual, as the females waited for the groups to range close together and then transferred without any interactions between the groups. Mutobo and his group welcomed the new additions, and he seemed excited by the new mating opportunities, which will likely lead to more newborns in the near future and a continuing expansion of the family.
Protecting the group
However, being the only silverback poses risks, as other lone males may try to attract some of the females. So far, Mutobo’s large size and confidence have deterred rivals. As his male offspring grow, they will be able to assist Mutobo in group protection in the future. Four-year-old Kazenea will soon learn to support his father, for example, but it will be several years until he reaches an adult male size.
Interestingly, two senior females, Nzeli (age 37) and Mudakama (age 38), are in Mutobo’s group, adding value to the group with their experience. This also shows that Mutobo is an excellent protector, able to gain the trust of females in their mature years.
Nzeli, one of the most mobile females we know, has changed 10 groups in her life, joining Mutobo on March 29 and leaving her son Kabeho with his father in her former group. We are curious to see if Mutobo’s success will keep Nzeli for long.
The transfers of Nzeli and other recent females to Mutobo’s group adds a fascinating layer to his success. It also highlights the dynamics of their former group – Kureba’s group – suggesting more interesting developments to come. This reflects the incredible variation in gorilla social life: while one male can attract females quickly, another can lose them all. Stay tuned for next month’s updates!
This article is part of a series presented by the Fossey Fund’s gorilla program Senior Advisor Veronica Vecellio, focusing on the mountain gorillas the Fossey Fund protects and studies every day in Rwanda. Veronica has worked with these gorilla families for 20 years and shares her deep knowledge and insights about their lives.
