Robert R. DeCosta was born on May 17, 1959, in Miami, Florida, and moved to Nantucket when he was three weeks old. Growing up in Nantucket, he began his career in the fishing industry at nine, working as a mate on his father's charter boat, the Albacore. Over the years, DeCosta took on various roles within the fishing industry, including construction work in the off-season and selling real estate. He became the captain of the Albacore in 1994 following the passing of his father.