Ironically, health risks to the gorillas have increased with the growth of gorilla tourism. Sharing 98% of human DNA, mountain gorillas are very susceptible to contracting human illnesses. Strict ‘gorilla etiquette’ rules apply when tracking, including observing a minimum distance of 7 meters and preventing anyone from tracking if they have a cold or other transmittable diseases.
Nevertheless, it is not unheard of for gorillas to break the rules themselves, and approach human visitors. Sometimes rangers will advise you to step back, and sometimes there is little you can do to avoid contact. Let’s face it—if a two hundred pound silverback decides he wants to ruffle your hair, there is little you or anyone else can do about it.
It happened to one of our clients, in a chance encounter with a gorilla group passing through the gardens of his lodge. His experience was captured on video and used to promote the African Wildlife Foundation, one of the major long-term supporters of gorilla conservation, yet the inadvertent close contact is seen in the film initially raised a few eyebrows in conservation circles.
The truth is, whilst Gorilla Doctors have identified the cause of death for some gorillas as infections that have originated as human viruses, they have not been able to say whether these came from the local community or visiting tourists.
Equally, gorillas also have their own viruses and bacteria. Currently, the team is collecting samples from the Sabyinyo group in Rwanda, which recently suffered a serious outbreak of respiratory illness. They may never ascertain the origin of this particular family’s problems, but there is an ongoing debate about whether tourists should do surgical masks while on a gorilla trek in Rwanda in order to minimize the chance of passing on any contagious diseases.
Furthermore, it seems there is a surprising correlation between habituated gorillas (gorillas that have learned to accept the presence of humans) and faster rates of population growth. Gorilla Doctors have ascertained that the annual rate of growth for the habituated gorillas in the Virunga is more than five times that of the un-habituated gorillas in the same area.
They attribute this pattern to the fact habituated gorillas can more easily benefit from ‘extreme conservation practices such as medical intervention. Simply put, completely wild gorillas are harder to treat when they develop illnesses, injure each other, or get trapped in snares. So while habituated gorillas may be more vulnerable to human illnesses, the net result of their habituation is having a greater chance of healthy population growth.