Concer belonged to the Pyrrhus family and worked as a farmhand until 1832 (slavery in New York formally ended in 1827) when he worked on whaleships out of Sag Harbor, New York.
In 1845 he was aboard the ship captained by Mercator Cooper that picked up shipwrecked Japanese sailors in the Bonin Islands. The American boat was allowed to enter Tokyo Harbor under escort to return the sailors and Concer became an object of curiosity and is depicted in Japanese drawings of the event.
In 1849 he joined many of the people from the East End in the California Gold Rush. Afterwards he returned to Southampton where he operated a small boat on Lake Agwam. A monument to him is by the lake on the northwest corner by Pond Lane. He is buried in the North End Cemetery in Southampton with his wife (across the Cooper's home). His tombstone says:
- THOUGH BORN A SLAVE
- HE POSSESSED THOSE
- VIRTUES, WITHOUT WHICH,
- KINGS ARE BUT