WEST AFRICAN COAST
Development, and hunting have diminshed populations. In some cases, lack of previous monitoring means that populations may be at even greater risk since earlier population numbers are unknown
 

CROSS RIVER GORILLA

HOME Nigeria, Cameroon
POPULATION 150 to 200

Found in the forested hills along the border between the two countries, it was recognized as a subspecies distinct from other West African gorillas only last year

PHOTO: KELLY MCFARLAND
     

DRILL

HOME West Africa
POPULATION unknown

Hunted for its meat, it is considered the top primate-conservation priority in the region

PHOTO: KEVIN SCHAFER/CORBIS
 
     
 

SCLATER'S GUENON

HOME Nigeria
POPULATION 2,000 to 3,000

Hurt by hunting, farming, logging, firewood collecting and oil-industry operations, it is protected only in two villages, where it is considered sacred

PHOTO: NOEL ROWE
     

WHITE-NAPED MANGABEY

HOME Ghana, Ivory Coast
POPULATION 2,000 to 3,000

So common in the 1950s that it was considered a crop pest, it is found in only a fraction of the forests it once roamed

PHOTO: RUSSELL A. MITTERMEIER
 
     
 

MISS WALDRON'S RED COLOBUS

HOME Ghana, Ivory Coast
POPULATION unknown

If an African expedition turns up no evidence of this colobus, it may have been the only primate to become extinct in the 20th century

ILLUSTRATION: PZS