Hr returns to the Millbrae after two seasons in Major League Rugby and will link up with ex-teammate Pat MacArthur.
Bulls have also added Richie Simpson who earns his first contract after impressing for Ayr's First XV last season.
Also joining the Bulls squad is former Scotland age-grade representative Will Hunt. The fly-half arrives from Cascais Rugby in Portugal.
Alongside the new signings, Rory Jackson returns to Millbrae on a full contract, having been previously involved as a Stage 3 Academy player.