Since time immemorial, the waters of the Pacific Northwest have been a home for salmon, nourishing the land and its people. However, as the impacts of climate change on ocean environments intensify, risks to salmon populations evolve with them.
To protect Pacific salmon populations, the federal government implemented Canada's policy for conservation of wild Pacific salmon as a “commitment to maintain healthy and diverse populations” for fisheries and uphold sustainability for future generations. But how has the policy been implemented? A team of researchers at UBC reviewed the policy’s impact on salmon populations, while considering rising environmental effects.
The article, published in February 2026 in the Canadian Journal of Fisheries and Aquatic Sciences, was led by Dr. Jacob Lerner, post-doctoral research fellow at the Pelagic Ecosystems Lab, and Dr. Anna McLaskey, research associate in the same lab at the UBC Institute for the Oceans and Fisheries. Their article examines potential approaches to managing vulnerable populations amid rapidly changing marine ecosystem conditions, particularly the emergence of thiamine deficiency complex (TDC) among salmon.
“[Pacific salmon] are important to people in B.C.,” said Lerner. “[They are] a very exciting species of study, and that's partly because of their exciting, fascinating life cycles that bring them from terrestrial systems to the high seas.”
The life cycle of Pacific salmon happens across thousands of kilometres, as they migrate from freshwater sources to the ocean and back again. Pacific salmon incubate as eggs and alevin (newly-hatched salmon) in rivers — a stage known as fry migration, during which they remain in the river typically for a few months to years. They grow in estuaries for days to months before migrating to the ocean to live for the next one to seven years. They travel back to freshwater to spawn or die.
“[The salmon] pass groups of people and communities over broad swaths of space and geography, and they connect these two very different systems: ocean ecology and ocean food webs,” said Lerner.
In 2023, the B.C. Salmon Fishery reported $58 million for wild salmon exports, with landed value for marine and inland reaching $23 million, highlighting the economic role of Pacific salmon in the province.
However, as the impacts of climate change intensify wild salmon populations are at risk. Thiamine (vitamin B1) is a nutrient required to process food sources into energy. For Pacific salmon, thiamine comes from their prey. But ocean warming and stratification affect thiamine supply in the ocean, and impact thiamine levels in the salmon food sources. This allows TDC to evolve quickly with little warning. Low thiamine levels have widespread impacts on salmon health, including high mortality of fry because of insufficient thiamine in salmon eggs.
According to Lerner, when salmon eggs emerge from the gravel, the juvenile salmon that are on the thiamine-deficient yolk sac will show neurological issues, such as irregular swimming patterns, that make it difficult for them to find food.
To address TDC, the researchers outlined strategies to support young salmon populations, such as bathing eggs in thiamine-rich water or injecting it into females before they lay eggs. More research is also needed to examine treatment strategies beyond early life to better assess long-term management of TDC. Ultimately, researchers need to determine whether current efforts are enough.
The Wild Salmon Policy has established numerous programs to improve salmon conservation, such as conservation units (CU), which are monitored groups of salmon isolated that reflect genetic and geographic diversity, used to assess populations and implement relevant solutions. The policy presents a clear outline to integrate broader ecosystem effects and incorporate ecological research into management options.
Past the policy efforts to improve ecological research include a Salmon Data Reporting Strategy and Workplan to standardize data collection methods, as well as a method to estimate CU benchmarks from observations of salmon populations when data is limited. The article also looks forward to seeing increased integration of TDC into management, whether in hatcheries or salmon production models.
However, some challenges still exist, such as difficulty conducting and implementing mechanistic studies. These use models to predict conditions impacting ecological dynamics, such as food availability and predation risk. According to Lerner, since salmon fry is hard to observe in nature, the researchers need to visit the hatcheries, spawn the eggs in controlled conditions, and observe the survival of the fry to monitor thiamine levels. However, real-life ocean conditions are much more complex and may take much longer to monitor.
“It takes a lot of research to identify specific mechanisms affecting fish or defecting ecosystems. And once you identify them, things can potentially change over time, [which] requires consistently going back and confirming these mechanisms,” said Lerner.
Similarly, McLaskey points out the computational demands for mechanistic studies to better investigate the ecological dynamics affecting salmon populations. There are many complex relationships between salmon and their environment, and researchers must have knowledge of each of these relationships. Modelling this complexity requires heavy computation and data studies.
Regarding future outcomes for salmon research and management, McLaskey said that more work needs to be done on collaborating with several levels of management. This includes local, provincial and federal governments, as well as more Indigenous communities, which already have efforts in place like salmon parks and the creation of salmon spawning beds.
“The most important thing is to start with building relationships,” said McLaskey. “You just need to start from a different perspective … and [find] the middle ground where your skills and needs align. Oftentimes, projects take twists and turns and are less focused on traditional academic outcomes, so it's important to have a different mindset.”
Meanwhile, Lerner described the constant need for further research on salmon populations and more consistent funding for that research.
“The climate is changing. Salmon populations are shifting, and so it is really important to stay on top of the drivers of these populations, with support for this holistic type of research where we understand the mechanisms affecting salmon from the bottom up,” said Lerner.
