Ras Nouadhibou (Arabic: رأس نواذيبو‎) is a 40-mile peninsula or headland in the African coast of the Atlantic Ocean by the Tropic of Cancer. It is internationally known as Cap Blanc in French or Cabo Blanco in Spanish (both meaning "White Cape").

Cabo Blanco, in the Atlantic Ocean, is the only place in the world having a monk seal colony. The largest surviving single population of the species, and the only remaining site which still seems to preserve a colony structure. In the summer of 1997, two-thirds of its seal population were wiped out within two months, extremely compromising the species' viable population. While opinions on the precise causes of this epidemic remain divided (the most likely cause being a morbilivirus or, more likely, a toxic algae bloom,) the mass die-off emphasized the precarious status of a species already regarded as critically endangered throughout its range.

While still far below the early 1997 count, numbers in this all-important location have started a slow-paced recovery ever since. Currently, the population in this location is estimated at 150 individuals, down from some 310 in 1997, but still the largest single colony by far. The threat of a similar incident that could wipe out the entire population remains.

The Spanish interest in Western Africa in desertic coast of Sahara was the result of fishing activities carried out from the nearby Canary Islands by Spanish fishers. Spaniard fishers were seal fur traders and hunters,They were fishing and whaling in Sahara coast from Dakhla to Ras Nouadhibou from 1500 to present, extending by West coast of Africa to whaling humpback whales and whale calves, mostly in Cape Verde, and Guinea gulf in Annobon, São Tomé and Príncipe islands just to 1940.