The group included 27 women and four children. The boat had departed Senegal on November 20 and was intercepted off Mauritania early on Wednesday, the coast guard said.
Earlier in November, the coast guard rescued 227 migrants who had left Gambia and were found off the coast of Nouadhibou in the northwest.
Mauritania has become a key transit point for African migrants, with Nouadhibou serving as a hub for those attempting to reach Europe. The country has signed agreements with several European nations, including Spain, to curb irregular migration. In recent months, authorities have increased patrols in Mauritania’s territorial waters, intercepting dozens of boats carrying migrants en route to Europe.