
Pacific Salmon
Characterizing risks associated with tire-rubber derived contaminants in Coho and Chinook salmon habitat in British Columbia

Salmon catches on Canada’s west coast have declined precipitously in the last two decades as human impacts to abundance and diversity permeate across species and regions in BC. These declines are occurring despite millions of dollars invested annually in hatcheries and wild salmon recovery programs intended to sustain fisheries and rebuild wild salmon abundance. This is especially true in the Fraser River watershed, historically Canada’s greatest producer of wild salmon, where population declines have led to the
Committee on the Status of Endangered Wildlife in Canada (COSEWIC) listings for 43 distinct populations within four salmon species. These declines are due to a number of human caused stressors, including contaminants, habitat loss in watersheds and climate change impacts. The degree to which each stressor impacts the health of salmon is not known, severely hampering the design and implementation of effective recovery strategies for salmon. Tire associated contaminants have recently been discovered to be the likely cause of toxic injury and death (40-90%) of adult coho salmon returning to urban and semi-urban waterways in Puget Sound, Washington, USA. While contaminants have been
identified as one of the greatest threats to salmon health and survival, nothing is known about the population level impacts of contaminants in British Columbia, including the recently discovered ubiquitous tire rubber antioxidant (N-(1,3-dimethylbutyl)-N’-phenyl-p-phenylenediamine; 6PPD-quinone). The objective of this study is to characterize the presence and the associated risks of tire rubber derived contaminants in creeks close to semi-urban and urban areas that feed into BC’s salmon bearing rivers to assess the

impacts of tire-rubber derived pollution on Coho and Chinook salmon. Results from this work will further assess these harmful contaminants and their effects on salmonids, as well as advance Canada’s commitments to protect and restore aquatic ecosystems, including COSEWIC and SARA listed wildlife.