September 5, 2019 — Scientists from the University of British Columbia, Fisheries and Ocean Canada, and the Pacific Salmon Foundation have discovered three new viruses that infect endangered Chinook and sockeye salmon – including one that was previously thought to only infect mammals.
These fish are considered to be ‘keystone species’ – meaning they have a disproportionately large impact on their ecosystem, making them a high priority for conservation. However, populations of both Chinook and sockeye salmon have been declining in the Pacific Northwest for the last three decades despite increased fishing regulations.
Researchers believe viruses may be part of the cause of the salmon declines. To date, most research on salmon-infecting viruses has focused on the piscine orthoreovirus, or PRV. PRV can cause ‘Heart and Skeletal Muscle Inflammation Disease’ (HSMI) in Atlantic salmon, devastating farmed stocks. However, PRV does not have the same disease-causing effect on Chinook and sockeye salmon.