A recent study by the Pacific Salmon Foundation reveals that viral heart disease, specifically heart and skeletal muscle inflammation (HSMI), is more prevalent in open-net salmon farms in British Columbia than previously acknowledged. The study, published in the Aquaculture journal, identified HSMI in five out of seven open-net pen salmon farms located in the Broughton Archipelago near Vancouver Island.
The researchers highlighted that the disease-causing virus, piscine orthoreovirus (PRV), can spread to wild fish in the surrounding waters. Lead author Emiliano Di Cicco emphasized that the occurrence of the disease is significantly higher than what was initially believed based on their findings.
The study, which examined 749 salmon across the farms, indicated that nearly seven percent showed signs of HSMI. PRV’s role in causing HSMI has been a subject of debate, but recent experiments by Norwegian researchers have established a direct link, according to Di Cicco.
Infected Pacific salmon can experience various health issues such as anemia, inflamed hearts, damaged livers and kidneys, and jaundice due to PRV. Di Cicco urged the Department of Fisheries and Oceans (DFO) to reclassify the virus as pathogenic and align the diagnostic criteria for HSMI with global standards.
While DFO stated that it would review the study’s findings for future considerations, it emphasized that detecting a virus in farmed fish does not automatically imply impacts on wild salmon populations. The B.C. Salmon Farmers Association did not respond immediately to requests for comments but has previously dismissed concerns about PRV as “fearmongering.”
Collaborating with First Nations, the study underscores the importance of supporting salmon populations, which have historically been essential to Indigenous communities in British Columbia. Leaders from various First Nations expressed their concerns about the detrimental effects of open-net pen salmon farms on salmon populations and ecosystems, emphasizing the need for action to protect these vital species.
