Evaluating the usability of stress hormones in scales as biomarkers of chronic stress in Chinook Salmon smolts
PSSI Project Summary
Division: Ecosystem Sciences (ESD)
Section: Regional Ecosystems Effects on Fish and Fisheries
Organization: DFO
Session(s): Fish Health
Presentation Date(s): December 11, 2025
Speakers: Reid Williams
Abstract:
Chronic stress is often detrimental to the health and reproductive success of salmon, yet reliably measuring it is difficult. Recently, the stress hormone (cortisol) content of scales has shown potential in this regard. This lab study compares scale and plasma cortisol content of Chinook Salmon smolt under acute stress, and a combined chronic osmotic and thermal stress to evaluate the usability of scale cortisol as a biomarker of chronic stress under environmental stressors such as climate change.