Climate change is one of the primary factors influencing salmon habitat conditions in the marine environment. Climate change is increasing sea surface temperature, reducing salinity in coastal waters, and changing ocean chemistry with effects on ocean currents, species distributions, and community composition. Pacific salmon inhabit the ocean for a large duration of their life cycle (1–5 years) where they are impacted by these climate change effects. Some of these climate change effects are negatively associated with growth and survival of salmon during the marine phase. Growth during the early marine phase is particularly important due to mortality bottlenecks during the first marine year. Climate change effects impacting salmon growth may further threaten already declining salmon populations. Climate also influences salmon’s marine phase in the open ocean, although this phase is understudied and generally less understood than the early marine phase. Overall, there is strong evidence linking climate to salmon survival, so it is important to understand, monitor, and communicate climate changes in the ocean when determining at-risk populations and developing effective management strategies. Identifying and displaying relevant marine climate indicators can provide information on potential impacts to salmon populations and how they are changing with climate change.

This report was produced as part of the UBC BRITE Internship Program, a partnership between the University of British Columbia and various local governments and organisations in support of providing graduate students with opportunities to do applied research on projects that advance sustainability across the region. This project was conducted under the mentorship of the staff of the Salmon Watersheds Program.