Adult Chinook
Identifying priority contaminants in at-risk Southern Resident Killer Whales and their prey
Characterizing the nature, significance and origins of the many different pollutants found in high trophic level marine mammals is exceedingly difficult. The Southern Resident Killer Whales (SRKW) face significant threats from high levels of endocrine disrupting contaminants, alongside other anthropogenic threats. A science-based evaluation of the contaminants found in their diet (food webs), the development, adaptation and/or application of new tools to prioritize (rank) the pollutants of concern, and the delivery of refined guidance herein will support of the wider
conservation agenda for this at-risk species. The aim of this project is to determine which prey species and/or stocks are accumulating contaminants of concern in endangered SRKW. Studies in the past have painted a partial picture of the pollutants of
concern in the SRKW food web. For example, preliminary studies of chinook salmon suggest that some stocks are more contaminated than others which may be contributing to the high PCB burden in the whales. This underscores the value of generating new information on contaminant concentrations and profiles in dominant prey species and / or stocks of these two endangered whale populations. The use of these data combined with SRKW and SLE beluga tissue / fecal concentrations and habitat
(sediment) concentrations in food web models, and risk-based assessments will facilitate source identification, natural resource management, environmental assessments and habitat stewardship.
Relevant Lab Members – Stephanie Holbert (PhD)