Marshall has over 29 years of seafood marketing experience and is a director of North Queensland Trawlers, based in Cairns. He holds diplomas in Business, Management and Sustainability as well as a Graduate Certificate in Business Administration from Griffith University, Queensland. He is currently completing his Master of Business Administration (MBA), also at Griffith University.
Marshall is a former director of the Australian Council of Prawn Fisheries and is currently an industry representative on the Torres Strait Prawn Fishery Management Advisory Committee. He is also the President of the Queensland Seafood Marketers Association and has recently been appointed to the inaugural board of Seafood Industry Australia.