Gorillas and chimps are nearing extinction. The article linked below discusses how hunting and natural disease have more than halved their numbers over the last 20 years:
"By comparing the figures with a survey carried out in the early 1980s, the researchers conclude that on a conservative estimate, gorillas and chimpanzees have declined by more than half within 20 years.
Gabon and Congo account for around 80% of the world's gorillas and most of the common chimpanzees, so this is described by the study as a major conservation crisis.
Gorilla and chimp numbers have dropped more than 50% since 1983
"Without aggressive investments in law enforcement, protected area management and Ebola prevention, the next decade will see our closest relatives pushed to the brink of extinction," the Nature paper says. "
BBC