Ama (diving)

Ama , uminchu (in Okinawan) or kaito (in Izu Peninsula) are Japanese divers,
famous for collecting pearls. The majority of ama are women.

Japanese tradition holds that the practice of ama may be 2,000 years old.
 Traditionally, and even as recently as the 1960s, ama dove wearing only a loincloth. 
Even in modern times, ama dive without scuba gear or air tanks, making them a traditional sort of free-diver.