Area of Expertise:
Dr. Johnson conducts research on diseases, immunology, physiology and husbandry of aquatic animals. His research activities use a multidisciplinary approach and include collaborations with both national and international researchers from a variety of universities, government institutes and industry partners.
Disease research focuses understanding the nature of the relationships between fish and pathogens such as nodavirus (Atlantic cod), Aeromonas salmonicida (Atlantic salmon), Infectious hematopoietic necrosis virus (sockeye salmon) and the sea louse Lepeophtheirus salmonis (Atlantic and Pacific salmon).
He applies genomics, proteomics and traditional methods to investigate virulence mechanisms of pathogens, the establishment of carrier states, host immunosuppression and disease management techniques such as vaccination.
Some past/current research activities include:
- Studies on host-pathogen interactions (L. salmonis, IHNV)
- Studies on how husbandry and environmental conditions affect physiology, growth performance and disease resistance of Atlantic cod and salmon.
- Vaccine development (L. salmonis)
- Development of genomics resources and tools for the study of Atlantic cod (see: www.Codgene.ca) and bivalves (see: www.Mytome.ca)
- Disease surveys of wild Pacific salmon in the Strait of Georgia and Johnstone Strait
Select Presentation(s) / Publication(s):
Mimeault, C & Wade, J & Foreman, M & C Chandler, P & Aubry, Pascale & A Garver, K & Grant, Sue & Holt, C & Jones, Simon & Johnson, Stewart & Trudel, Marc & Burgetz, Ingrid & J Parsons, G. (2017). Canadian Science Advisory Secretariat (CSAS) Assessment of the risk to Fraser River Sockeye Salmon due to Infectious Hematopoietic Necrosis Virus (IHNV) transfer from Atlantic Salmon farms in the Discovery Islands, British Columbia.
Mahony, AM & Johnson, Stewart & Neville, Chrys & Thiess, Mary & Jones, Simon. (2017). Myxobolus arcticus and Parvicapsula minibicornis infections in sockeye salmon Oncorhynchus nerka following migration to the ocean in British Columbia, Canada. Diseases of Aquatic Organisms. 126. 10.3354/dao03158.
Freshwater, Cameron & Trudel, Marc & Beacham, Terry & Grant, SCH & Johnson, Stewart & Neville, CEM & Tucker, Strahan & Juanes, Francis. (2017). Effects of density during freshwater and early marine rearing on juvenile sockeye salmon size, growth, and migration. Marine Ecology Progress Series. 579. 10.3354/meps12279.
Neville, Chrys & Johnson, Stewart & Beacham, Terry & Whitehouse, Timber & Tadey, Joe & Trudel, Marc. (2016). Initial Estimates from an Integrated Study Examining the Residence Period and Migration Timing of Juvenile Sockeye Salmon from the Fraser River through Coastal Waters of British Columbia. North Pacific Anadromous Fish Commission Bulletin. 6. 45-60. 10.23849/npafcb6/45.60.