Wildlife of Sierra Leone
Sierra Leone has 15 identified species of primates that include bushbaby, monkeys and a great ape, the common chimpanzee which is Sierra Leone's largest primate. Chimpanzees are found across the country with the 2010 chimpanzee census estimated a wild population in excess of 5500 more than double the number previously thought to live in the country. This is the second largest population of the endangered subspecies of western chimpanzee, after Guinea,
with the largest density in the Loma area, 2.69 individuals per km2, and the Outamba, with 1.21 individuals per km2.
Prosimian
While primates are often thought of as fairly intelligent animals, the prosimians are not very large-brained compared to other placental mammals. Their brain-cases are markedly smaller than those of simians of comparable sizes. In the large-eyed tarsiers, the weight of the brain is about the same as that of a single eye. Prosimians generally show lower cognitive ability and live in simpler social settings than the simians. The prosimians with the most complex social systems are the diurnal lemurs, which may live in social groups of 20 individuals. The nocturnal prosimians are mainly solitary.