How do interactions in gorilla groups unfold?


Gorilla groups occasionally interact with one another but the process can unfold in various ways with some peaceful and friendly while others can be very hostile and brutal. Male gorillas in particular are always in the mix during these interactions as they to multi-task by ensuring safety for their group, try to attract females from other groups and at the same time prevent their females from joining other groups. This kind of gig leaves male gorillas posturing and displaying during interactions hence making them very intense.

On the other hand, interactions between gorilla groups can also be peaceful and friendly with groups associating for hours. Several wildlife researchers have carried out studies in order to understand the variability associated with intergroup interactions among gorillas. The studies analyzed data published about group interactions and gorilla behavior in different gorilla groups which are monitored by the Fossey Fund through the Karisoke Research Center in Rwanda. One of the objectives of the study was to find out what influences gorilla interactions at group level.

Among the findings, it was established that intense fights tend to be frequent between groups that are comparable in size and whose members do not know one another. Dominant male gorillas were found to be more involved in interactions than other categories. Males get involved in conflicts more frequently as they try to defend their mating opportunities. Aggressive interactions were also observed between female gorillas and lone silverbacks and this was attributed to the need by females to avoid the risk of infanticide in case a dominant male is killed or injured. Peaceful interactions involved individuals familiar who are likely to have been born in the same group before splitting to form of join other groups.

Researchers also observed that fighting between groups created a lasting impact on how members group members interact with each other in the aftermath of the conflicts. It was observed that females increased their positive social interactions with group members after an intergroup conflict. The aggressive interactions of males with group members were also observed to have decreased. The two groups involved in a conflict doubled the time they spent moving while the losing group reduced its resting time too.

Though not witnessed, it is also believed that intergroup conflicts might be one of the reasons that forced Nyakagezi gorilla group to migrate from Volcanoes National Park in Rwanda to Mgahinga Gorilla National Park in Uganda in 2019. The group has since returned to Rwanda probably after sensing that its original home might be calm again.

According to researchers, studies into gorilla interactions not only help them understand their behavior, but also provide insight on the space needed by gorillas to accommodate their increasing population density. They also add that understanding the dynamics around group interactions in vital for conservation. It is highlighted that while the population of mountain gorillas continues to increase, the habitat available for them does not and increasing interaction with increasing competition are likely to affect future population of the gorillas. Understanding the causes of intergroup aggression can potentially help researchers predict its effects on the increasing population of mountain gorillas.