Marine Life Monitoring in Puget Sound

Project Overview

One crew, two weeks, 200 nautical miles, and 23,000 fish! Every year, Long Live the Kings joins in an ongoing offshore monitoring effort in Puget Sound led by The Tulalip Tribes in partnership with USGS. The crew gathers important biological information from salmon and other marine life to get a snapshot of marine health and to learn more about what’s causing the persistent low marine survival rates for salmon.

The Problem

Climate change is advancing on Puget Sound’s salmon. Oceans are warming and weather patterns are changing, causing unpredictable ripple effects in the marine food web. The Salish Sea Marine Survival Project identified climate-driven changes to food supply as a main reason juvenile salmon are dying at high rates. However, seasonal environmental conditions vary from year to year and location to location. There are still many unanswered questions about how these complex relationships are affecting salmon from different watersheds. For salmon to survive in the long run, managers and recovery planners need annual data that helps connect the dots between weather patterns, plankton, forage fish, and salmon – locally, and across the Puget Sound ecosystem.

By creating a long-term, Puget Sound-wide monitoring network, we hope to answer two crucial questions for managing salmon through climate change:

  • Which mechanisms in early marine life impact survival?
  • Can we identify ecosystem indicators to improve forecasting and salmon recovery efforts?

Our Solution

The Tulalip Tribes, a partner in the Salish Sea Marine Survival Project, has secured funding from the Bureau of Indian Affairs Tribal Climate Resilience branch for five years of monitoring surveys focused on juvenile salmon and Pacific herring, their key food source, during the critical summer growth period in Puget Sound. In partnership with Long Live the Kings and USGS, the Tulalip Tribes are leading these surveys which we hope will be the foundation for a collaborative long-term regional monitoring program of salmon and their food web.


These surveys are like an annual checkup for Puget Sound’s salmon stocks: sampling juvenile salmon gives an early indication of how well different populations are doing during their critical first summer in salt water. By collecting data about salmon prey and environmental conditions at the same time, we can build a better picture of the relationships between salmon health and factors like water temperature, plankton, and forage fish. Understanding the marine factors that limit salmon returns is critical to informing habitat, harvest, and hatchery management and evaluating salmon recovery efforts, especially with the increasingly uncertain impacts of climate change.


On each survey, the research team spends two weeks on a purse seiner fishing vessel, traveling from the San Juan Islands to the southern end of Puget Sound and Hood Canal. We sample both fish and environmental conditions at up to 18 locations, covering salmon populations from more than 10 watersheds. In addition to abundance, age, and growth data on salmon, the study is collecting essential information about salmon diets and food supply. This means looking at what salmon have in their stomachs (using non-lethal methods on listed species like Chinook). A good sign is seeing plenty of energy-rich fish, especially herring, both in the sample net and in salmon stomach contents.


At each sample site, we also follow the protocols of the Zooplankton Monitoring Program to provide a snapshot of the base of the food web, and collect environmental data about temperature and salinity. Linking this environmental data to the health and diets of salmon is critical to developing indicators to track the Puget Sound ecosystem over time.


We are urgently pursuing sustainable funding to support a long-term collaborative monitoring program to provide robust data and support sustainable management options for all Puget Sound salmon stocks in a changing environment.

Project Impact


Nautical Miles Traveled


Salmon Stocks Impacted


Fish Sampled

Project Partners

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Project Contact

Liz Duffy

Associate Director of Science (she/her)