Researchers are taking a close look at how an oil spill in freshwater habitat will affect the physiology and health of B.C.’s coho salmon.
The University of Guelph study comes ahead of the late-2022 completion of the TransMountain Pipeline Expansion project that will triple the outflow of millions of litres of diluted bitumen from the Alberta oil sands to Vancouver. The research, led by Prof. Todd Gillis and Dr. Sarah Alderman at the U of G’s Department of Integrative Biology, was spurred by public concern of how a pipeline rupture will impact imperilled salmon populations in the Fraser River Watershed.
“It’s an ambitious project,” said Alderman, “but these data are essential for making informed decisions on how to protect salmon, before or after a spill.”
Coho spawn in over half of the 1,500 streams in B.C. and Yukon, generally spending one year in freshwater. In northern populations, most juveniles spend two or three years in freshwater before entering the ocean.
With $350,000 in funding from the federal government’s Oceans Protection Plan – Fate, Behaviour, and Effects Initiative, which aims to better understand oil spill behaviour and its biological impacts, the two-year study will determine which life stages of the salmon are most vulnerable to diluted bitumen, whether higher temperatures in contaminated water alter egg development and whether the fishes’ sense of smell, which they use to locate their natal streams, is impaired by exposure to the substance.
Alongside colleagues at Simon Fraser University and the University of British Columbia, the U of G researchers have received $1.2 million in funding over the past six years to address knowledge gaps in early life stages of salmon exposed to diluted bitumen, contributing to a broader understanding of the impacts of contaminants on fish and fisheries.
The group was the first to publish studies describing how even a small amount of diluted bitumen can affect salmon development, and impair their ability to swim.
“So a spill into a salmon-bearing river could be devastating to populations that are already struggling,” Alderman said.