Everald Pickersgill (born 4 November 1954), better known as David Jahson, is a Jamaican reggae singer, active since the early 1970s.

Born in Kingston, Jamaica in 1954, Pickersgill first recorded in 1970 for Clement "Coxsone" Dodd's Studio One, but the results were only released on sound system dub plates. In 1972 he recorded "Far I" for Byron Lee's Dynamic studio, which was released on the Jaguar label, miscredited to 'David Janson' and mis-titled "For I", reaching number seven on the JBC singles chart. Feeling that Dynamic had mishandled the single, his next release was the self-produced "Child of a King", released on the Ital Lion label through Pete Weston's Micron label. In 1975 he recorded his most well-known song, "Natty Chase the Barber", using a new version of John Holt's "Ali Baba" rhythm recorded by a band including his friend Sly Dunbar at Channel One Studios and mixed at King Tubby's. The single was released by Tommy Cowan on his Arab label, miscredited this time to 'David