Contrary to the popular beliefs, group thirteen has more than 13 individuals. This group came to be thirteen to the order in which it has been localized. At that time groups could be named according to the order in which contacted. Method initiated by Dian Fossey.
This group has never had more than one silverback in its history and that is why after the death of the leading silverback Murith in 1992 it led to the loss of all adult females to other silverback forming Sabyinyo group and leaving Group thirteen with only three young males that could not lead the group.
However, these young males: Munani, Nyakarima and Kwirinda stayed together until the older one named Munani turned to silverback but then Nyakarima left the group and Kwirinda died of injuries due to interaction with another group.
Munani, being a silverback who wanted to form his group at any cost, had an interaction with group Sabyinyo and obtained Safari one female which was also a member of group eleven before being Sabyinyo member. He also obtained two other females Gukunda and Cyuzuzo. In 2002 the silverback died of a natural death leaving seven members with a black back which together with the oldest female (Safari) led the group for five months until when a new silverback came to take over the group.
The new Silverback which is named Agashya came with three members with him increasing the group to ten individuals. However, the black back he met in the group refused to submit to the new silverback and left the group to a solitary life.
After Agashya gained power he has increased the group for 27 individuals in only eight years with nine adult females. The name Agashya meaning something special is related to ability to lead such a big group of 23 gorillas and that is why last year in June, 2011 the group was named AGASHYA FAMILY.