Toxic contaminants in outmigrating juvenile Chinook Salmon (Oncorhynchus tshawytscha) from river mouths and nearshore saltwater habitats of Puget Sound


Published: July 2013

Pages: 51

Author(s): Sandra O’Neill, James E. West, Lyndal L. Johnson, Jennifer Lanksbury, Laurie Niewolny, Andrea Carey

This study is funded in part by the United States Environmental Protection Agency (EPA) National Estuary Program (NEP), under Puget Sound Ecosystem Restoration and Protection Cooperative Agreement grant G1200486 with Washington State Department of Ecology (Ecology). This Quality Assurance Project Plan (QAPP) describes the overall study but the grant mainly supports field activities, data analysis, and final reporting. The QAPP and final study report will be available from the Washington State Department of Fish and Wildlife (WDFW).

Chemical analysis of the field samples collected by WDFW and NOAA for this project will be conducted under a different agreement between Ecology and NOAA’s Northwest Fisheries Science Center (#C1300124, attached).

The contents of neither of these documents do not necessarily reflect the views and policies of the EPA, nor does mention of trade names or commercial products constitute endorsement or recommendation for use.


Juvenile Chinook salmon (Oncorhynchus tshawytscha) can encounter a wide range of water quality conditions, from relatively clean to highly contaminated, as they migrate from freshwater to saltwater in Puget Sound. During this life stage they are particularly sensitive to stressors such as toxic contaminants as they transition from fresh to saltwater. Currently, contaminant monitoring in juvenile salmon is not funded; however, it is a central metric of the Puget Sound Partnership’s Toxics in Fish Vital Sign, adopted in 2011 by the Leadership Council. In this study we will measure juvenile Chinook salmon exposure to known chemicals of concern entering Puget Sound via stormwater, wastewater treatment facilities, atmospheric deposition to marine waters and groundwater. Fish will be sampled from four Puget Sound embayments in 2013. For each embayment, sampling sites include one location in the lower river and two locations along adjacent marine shorelines. This sampling augments previous sampling initiated as early as 1998, and will be used to establish a solid time series of contaminant conditions in juvenile Chinook salmon that can be used to fulfill the Toxics in Fish goal of tracking time trends of salmon health. The objectives are to (1) measure the magnitude of exposure, (2) compare exposure in outmigrants across four major embayments and between fresh- and saltwater, and (3) evaluate potential effects on marine survival. Additionally, results from this work will be used to provide a measure of the effectiveness of current toxic reduction strategies and actions, inform future pollution reduction efforts, and enhance recovery of Chinook salmon. This project is linked to an agreement between Ecology and NOAA’s Northwest Fisheries Science Center (#C1300124, attached), who will conduct chemical analyses on field samples collected by WDFW and NOAA.

Upon completion of the study, WDFW will produce a final report detailing the findings. The final report will be published and data will be submitted for uploading into Ecology’s Environmental Information Management database.