Liberia, a country along the West African coast. Liberia's topography ranges from low and sandy coastal plains to hills and indented plateaus inland. The country has lush rainforest with a rich flora and fauna. It is the only Black state in Africa that has never been under colonial rule and is Africa's oldest republic. It was founded on the land acquired for freed American slaves by the American Colonization Society, which in 1821 established a colony at Cape Mesurado. The territory was named Liberia in 1824 and its main settlement Monrovia, the present capital. Liberia declared independence in 1847 and its borders were extended. Liberia is a hotspot for biodiversity and has the largest remaining forest area in the Upper Guinea Massif, with many species endemic to the region. This ecosystem of humid coastal forest extends from Liberia through Côte d'Ivoire, Ghana and Sierra Leone to Togo, and is threatened by deforestation and coastal development. There are more than 2000 plant species in Liberia, including 225 tree species, 140 mammal species, more than 600 bird species and 75 species of reptiles and amphibians. The Pygmy Hippopotamus is found in riverine forests inland, such as along the Lofa, Cestos and Cavalla Rivers. African Manatee is also found in coastal areas and in many river systems. Other species of mammals present in the forests include leopards, monkeys, chimpanzees, antelopes, elephants and anteaters. There are 695 bird species recorded in Liberia, some of which are resident and some migratory, and 21 of which are globally threatened.