Dear Dr Zaytsev,
You may have heard about the Bushmeat Crisis in central Africa and - in fact - all through the tropics.
Hunting tribesmen have never posed a threat to wildlife, for they killed for their own food only. Nowadays, pygmies a.o. are being provided with firearms and payed by local businessmen to go and hunt as many animals as they can get, indifferent of size, species or officially protected status. The smoked meat is sold in cities or even abroad and looked upon as delicatesses by the snobist buyers.
Efficient transport out of the jungle is made possible by the large logging roads. The thousands of loggers are eager consumers themselves too.
Ancient taboos are being abandoned, making hunters go for beings they would have never killed otherwise, like gorillas, chimpanzees, bonobos (comes VERY close to cannibalism!) or elephants, among many others.
This currently poses a way bigger threat to many species (especially those mentioned above) than the destruction of their environment itself!
You should be able to find more on the subject in the internet, as well as with the EAZA (European Ass. for research in Zoos and Aquaria), Jane Goodall Institute and Karl Ammann.