The market for exotic animal body parts is varied - some parts are used in rituals, some are used as trophies, others yet are used for meat (refer to Bushmeat post December 2008 on this blog for more info).
According to an article published in the Gorilla Journal in 1999 by Angela Meder, even though most people now use western medicine, some traditions are still alive. For example, eating gorilla meat is believed to transfer the strength of the gorilla to the person consuming it; keeping dried gorilla hands is said to bring good luck.
Poachers are a reality those dedicated to the conservation of non-human primates have to contend with, however education and solutions to curb down poverty are key.
There are many initiatives in Africa and throughout the world to save endangered primates and help populations who share the same territory as them. Below are two videos highlighting such projects.
Watch Saving the gorillas in Rwanda - PBS documentary:
Watch - GAFI - the bike that helps save gorillas in Uganda: