There are 15 species of great apes -- the IUCN (International Union for Conservation of Nature), which is the main international body tracking this stuff, lists 14 of them as either "endangered" or "critically endangered" (the latter is the last step below "extinct"). And the 15th, non-endangered species is...
Homo sapiens.
According to the IUCN's
website, the three major threats to apes are habitat destruction (mining, logging, and slash-and-burn farming), poaching, and disease. They're hunted illegally ("bushmeat"), and they're susceptible to human diseases, so the more habitat is lost, the more they're pushed into contact with humans... and so it goes, in a vicious circle.
H. sap. has quite a bit to answer for in this regard.
