Dian Fossey Gorilla Fund trackers report that elderly and historic mountain gorilla silverback Cantsbee, who disappeared from his group on Oct. 10, and could not be found despite weeks of massive searching, was seen in his group on Jan. 4. Although the group was at some distance from the trackers and would not allow them to approach, a closer look on Jan. 5 provided evidence that the gorilla was indeed the missing Cantsbee!
Due to his advanced age (now 38 years old and beyond the statistical life expectancy for a mountain gorilla), the Fossey Fund had earlier presumed that he must have fallen ill, been left behind and subsequently died, since intensive searching over a month long period did not find any traces of him.
On their regular monitoring of Cantsbee’s former group on Jan. 4, Fossey Fund trackers were shocked to notice, from a distance of about 10 meters, that an “extra” silverback was in the group, which is now led by Cantsbee’s son, Gicurasi. They returned the next day determined to get conclusive evidence, including a closer look and photographs, and to determine the condition of the gorilla.
More surprises on the second day
Trackers reached the group later than usual on Jan. 5, due to the rough, steep terrain, full of ravines and dense foliage, as well as the distant location of the group. The group was split in two subgroups and our trackers first encountered one of these, led by young silverback Kureba. When they found the second subgroup, it was involved in an intense interaction with another group. But there was no doubt: elderly Cantsbee and silverback Gicurasi were leading the action and Cantsbee appeared to be in fine shape, running, displaying and smashing vegetation as a show of strength.
After about an hour, the whole group started to move away from the action, led by Cantsbee, with the females and youngsters following him, just like they used to in the past. Gicurasi and the younger silverbacks stayed behind, to continue facing off the intruding silverback, who was still following them. His name is Iyambere and he is a young silverback who just formed his group in 2015. Interestingly, he’s also another son of Cantsbee!
Field staff are amazed
“It’s hard to believe and to explain what has happened,” says Veronica Vecellio, Fossey Fund gorilla program manager in Rwanda. “We don’t know why Cantsbee left the group, where he went, whether he’s back to stay, and how he will work things out with Gicurasi’ dominance. But we are overjoyed to have him back so we can continue to monitor the oldest known silverback, who has been followed since birth and has such a remarkable story!”
“Cantsbee was named by Dian Fossey because she thought his mother was a male and so when she gave birth she said ‘it can’t be’. And now he has earned his name for a second time,” says Fossey Fund president and CEO/chief scientific officer Dr. Tara Stoinski.
“There are cases where younger males go off and return, usually as they try to establish their own future groups or status, but we have not seen a situation like Cantsbee’s return before. This shows that even after 50 years of close study, the gorillas can and will still surprise us and that there is always more to learn!”