For over 5 years, researchers at Salmon Coast have been using cutting-edge technology to study the transmission of viral and bacterial pathogens to wild salmon.
A New Way to Study Salmon
The use of environmental DNA (eDNA) is an exciting technology that has allowed researchers to efficiently and non-invasively monitor for disease risk in aquatic ecosystems. In 2018, University of Toronto PhD student Dylan Shea used these methods to explore the risk of exposure to disease to wild salmon as they migrate past salmon farms. The results found that BC salmon farms do drive disease transmission between wild and farmed salmon and therefore represent a clear concern for the conservation of wild Pacific salmon.
This work was continued in 2021 when the lab of Salmon Coast alumnus and University of Toronto Professor Dr. Martin Krkosek launched a new study to investigate viral transmission around salmon farms.
The field program aimed to generate long-term time-series data that could characterize pathogen assemblages around salmon farms in the Broughton Archipelago.
Researchers collect environmental DNA from water samples around active farms, inactive farms, and estuary sites. These samples are filtered and then screened via high-throughput qPCR in a laboratory setting. Analysis of this data will allow us to determine the prevalence of 45 pathogen species that infect salmon, variation in pathogen communities across space and time, and the extent of spread of pathogens from farm sites into the surrounding marine environment.
The backdrop of this work is the recent decommissioning of several active farms across the Broughton, which comes as a result of agreements among local First Nations, aquaculture companies, and the BC provincial government.
eDNA allows researchers to noninvasively explore disease risk to wild salmon.
Because our eDNA surveys were taken as the farms were removed, a feature of this fieldwork is its ability to detect the response of pathogen communities to the decommissioning of salmon farms, which may highlight how the removal of disease-induced stressors may affect wild salmon populations.
The use of eDNA technology has revolutionized the field of pathogen study, and researchers at the University of Toronto and Salmon Coast are continuing to employ innovative uses in support of conservation research .
Find out more about our work by checking out our regular reports and related publications
Check out our sea lice reports for each year, which provide detailed information on the year’s monitoring findings.
View our complete list of publications for many more articles based on sea lice research conducted at Salmon Coast.