Kuryama’s Group Interacts with Lone Silverback Gwiza

November 14, 2011

Kuryama's Group Out of Park Again, Interacts with Lone Silverback Gwiza

Fossey Fund researcher Winnie Eckardt, Ph.D. joined the Karisoke Research Center trackers to observe Kuryama’s group today as they were again herded back into the park. The group slept within the borders of the park, albeit quite close to the edge, and immediately exited the park after leaving their night nests. Umusatsi and Rwema were not with the group again today and their night nests were not among the other group members’ nests. When Dr. Eckardt reached the group this morning, the gorillas were already 300 meters from the park border. After a brief resting period, the group clearly intended to move further down from the forest in pursuit of more of the irresistible eucalyptus bark. The decision was made to begin to herd the gorillas back up the slope at 8:05 a.m. The trackers stopped the “push” at 9:40 a.m. when it was clear that the gorillas were headed back into the forest. But 20 minutes later they re-entered the park, where they remained for the rest of Eckardt’s four-hour observation period.
After some initial discrepancy in the identity of the lone silverback who had been traveling for four days with Ubufatanye (known as “Fat”), it was determined that he is in fact 24-year-old Gwiza, a male who parted ways with Shinda’s group in 2003. The Karisoke trackers had difficulty identifying the silverback due to distance, dense vegetation and the gorillas’ aggressive behavior. Gorilla Program Manager Veronica Vecellio says “The identification of a lone silverback is not always an easy task and it can be done by very few people. Part of the difficulty is due to the fact that they are not seen on a daily basis and their features may change with time. But with attentive observation, we are able to identify all of them. Photographs are extremely helpful in the identification process because it allows our staff to magnify the facial area and examine the noseprint.”
The lone silverback has been working hard to form his own group since he left Shinda’s group eight years ago. Not surprisingly, Gwiza is not going to give up his recently acquired female without a fight and the interaction that began yesterday (when Fat attempted to rejoin Titus’s group) is still playing out today. Fat has been causing a lot of trouble for Titus’s dominant silverback Rano in the past few weeks. Interestingly enough, Rano has not shown any interest in copulating with the female in quite some time, but still is not willing to let her leave the group. Gwiza has reportedly been following closely all day, periodically entering the group to display fervently. Rano led the other males in his group in aggressive displays in reaction to the lone silverback’s behavior while Fat retreated further into the group where, evidently, she wishes to remain. The group has traveled over 700 meters today, zig-zagging through the park in an attempt to avoid Gwiza. When the trackers left the gorillas this evening, the lone silverback was still in hot pursuit of his female, suggesting that this interaction could carry on into the coming days.
Jessica Burbridge, Field Communications Officer