Western chimpanzee

The western chimpanzee, or West African chimpanzee, is a critically endangered subspecies of the common chimpanzee that lives in the forests of West Africa, in Cote d'Ivoire, Guinea, Liberia, Mali, Senegal, Ghana, Sierra Leone and Guinea-Bissau, and has been lost from Benin, Burkina Faso and Togo. Its range once stretched from southern Senegal east to the Niger River, and the largest remaining populations are in Guinea, Sierra Leone and Liberia. It is the most genetically distinct subspecies of the common chimpanzee, and its behaviour is so different from the others that some have proposed it may be a species in its own right. Western chimpanzees sharpen branches into spears to hunt bushbabies, crack nuts with stones in Tai National Park, and show a more even balance between the sexes than eastern populations. The IUCN estimates between 21,300 and 55,600 individuals remain, and habitat loss is the chief threat, followed by killing for bushmeat.