FEATURED

Water Resource Inventory Areas (WRIA). Map: Kris Symer. Data source: WAECY.

Geographic boundaries of Puget Sound and the Salish Sea

The boundaries of Puget Sound and the Salish Sea are not always consistently defined by scientists and government agencies. This article clarifies the distinctions between oceanographic and watershed-based definitions of these geographic areas. 

Join the PSI mailing list

If you are interested in Puget Sound recovery strategies, Salish Sea Currents magazine and the Puget Sound Institute (PSI) newsletter, we invite you to join our mailing list.

Subscribe

TOPICS

RECENT ARTICLES

Person standing on a paddle board with the Seattle skyline in the background.
2/8/2024

Puget Sound perceptions of environmental and climate change

A summary report on perceptions of environmental and climate change based on the 2022 human wellbeing Vital Sign survey. This research was funded by the Puget Sound Partnership and led by members in Oregon State University’s Human Dimensions Lab.

Colorful graphic showing chart of Puget Sound Vita Signs.
2/8/2024

Summary report of 2022 human wellbeing Vital Signs survey

This report presents results of the 2022 survey to monitor the human wellbeing Vital Signs prepared for the Puget Sound Partnership by Oregon State University.

Chemical symbols for QPPD and QPPD-6 overlain on image of black car driving on wet road
1/30/2024

Lawsuits fly, as regulators come to grips with a toxic tire chemical

Finding a replacement for 6PPD in tires is one major challenge; another is to prevent the highly toxic derivative 6PPD-Q from reaching salmon streams and killing fish.

Car wheel and tire next to a pothole puddle.
1/9/2024

Scientists worldwide are immersed in studies of a deadly tire chemical

Research that began in Puget Sound has revealed much about the cellular-level assault on vulnerable salmon and trout, yet the puzzle remains incomplete.

A coho salmon fry about 1.5 inches long watches for food below the Salmon Bone Bridge at Seattle’s Longfellow Creek.  Designed by the late sculptor Lorna Jordan, the bridge honors the creatures that so far keep returning to spawn. Photo: Tom Reese
12/28/2023

Photographing the 'Creek of Hope'

Longfellow Creek near West Seattle's industrial district still draws spawning salmon despite a century of city development and an onslaught of toxic chemicals. A current exhibit by photographer Tom Reese explores this often-overlooked gem of urban nature.

An adult elephant seal resting on the shore with water in the background.
12/4/2023

Northern elephant seals in Puget Sound and vicinity

Northern elephant seals were hunted heavily in the 19th century and believed to be extinct by 1892. However, a small remnant population (~50–100 animals) off the western coast of Mexico grew to populations in the United States and Mexico to at least 220,000 individuals as of 2010. Elephant seals are distributed in the central and eastern North Pacific Ocean, from as far north as Alaska down to southern Baja California. Sightings of elephant seals were once considered rare in the Salish Sea, but increasingly single individuals are known to haul out onto sandy beaches on Smith, Protection, and Whidbey Islands. In 2010, a local breeding population established itself along the lower west side of Whidbey Island in Puget Sound.

Image of a sailboat on the water at sunset.Text overlay reads: Puget Sound Marind Waters 2022 Overview.
11/28/2023

Puget Sound Marine Waters 2022 Overview

Each year, the Puget Sound Ecosystem Monitoring Program releases the annual Puget Sound Marine Waters Overview report. The latest report combines a wealth of data from comprehensive monitoring programs and provides a concise summary of what was happening in Puget Sound’s marine waters during 2022. The report represents the collective effort of 84 contributors from federal, tribal, state, and local agencies, academia, nonprofits, and private and volunteer groups.

A stream full of hundreds of swimming salmon.
11/21/2023

Surging numbers of pink salmon raise ecological concerns

An estimated 70% of all the salmon in the North Pacific are pink salmon. Scientists say the extreme abundance of pinks could be causing a "trophic cascade" that is harming species across the food web.

Report cover
11/6/2023

State of the Sound report 2023

The 2023 State of the Sound is the Puget Sound Partnership’s eighth biennial report to the Legislature on progress toward the recovery of Puget Sound. The document reports on both the status of the Partnership's recovery efforts and a suite of ecosystem indicators referred to as the Puget Sound Vital Signs.

Aerial view of Interstate 5 stretching across a large area of land covered by brown flood waters from the Nooksack River in the foreground with mountains and Puget Sound in the distance and grey skies above.
10/30/2023

Studies target increasing flood risks

All across the region, communities are finding that rising seas and rising rivers are two sides of the same coin. New research funded by the Environmental Protection Agency may help managers target their responses to climate-fueled flood risks in Puget Sound. The following article was commissioned by the Habitat Strategic Initiative Lead (HSIL), a cross-agency team co-led by the Washington Departments of Fish and Wildlife and Natural Resources.

Two people standing on a boat hosing off two long, black sampling nets that have been pulled out of the water by a small crane.
10/30/2023

The ups and downs of zooplankton in Puget Sound

Zooplankton are critical to the marine food web, but until recently there have been few surveys of the zooplankton community in Puget Sound. Ongoing monitoring is now revealing a system full of complexity and surprises. The following article was commissioned by the Habitat Strategic Initiative Lead (HSIL), a cross-agency team co-led by the Washington Departments of Fish and Wildlife and Natural Resources.

A beaver sitting at the base of small tree on mud surrounded by green vegetation.
10/30/2023

Program seeks alternatives to beaver dam removals

Beavers provide critical benefits for wetland ecosystems but can also alter the landscape in ways that are unpredictable for property owners and conservationists alike. New techniques are helping humans and beavers share the landscape with the goal of benefiting both parties. The following article was commissioned by the Habitat Strategic Initiative Lead (HSIL), a cross-agency team co-led by the Washington Departments of Fish and Wildlife and Natural Resources.

A killer whale surfaces with its head above water holding a harbor porpoise in its mouth.
10/19/2023

Southern resident orcas chase and sometimes kill porpoises. Why don’t they eat them?

Puzzling encounters between endangered killer whales and harbor porpoises point to questions about prey availability and whale culture, scientists say. Are the whales playing, practicing their hunting skills, or is something else going on? 

A person wearing a Tyvek suie and orange vest standing on a beach next to two full garbage bags. Water, land, and blue sky in the distance
10/1/2023

Avian flu comes to the Salish Sea

A new strain of avian flu has been sweeping the globe since 2020, leaving thousands of dead seabirds in its wake. This past summer, it arrived at a colony of Caspian terns at Rat Island in the Salish Sea, with catastrophic results.

A grey and white harbor seal swimming in water
9/26/2023

Status and trends for harbor seals in the Salish Sea

Harbor seals were hunted from the 1870s to 1970s until they were protected in the United States by the 1972 Marine Mammal Protection Act and in Canada under the 1970 Marine Mammal Regulations in the Fisheries Act. The inland Washington harbor seal stock is estimated to be over 12,000, while the Strait of Georgia sustains approximately 39,000 harbor seals. Key threats include human disturbance, habitat degradation, loss of prey, and interaction with fishing gear and boats.

A beaver swimming in a pond with vegetation in the background.
9/26/2023

Can the age-old affinity between beavers and salmon be restored?

Salmon restoration groups are learning how to work with beavers to create better salmon habitat. The process hinges on reducing human-beaver conflicts while taking a natural approach to ecosystem recovery. The beavers are happy to help. 

A much larger male Stellar sea lion sitting next to a male California sea lion on a rocky perch.
9/20/2023

Steller sea lions in Puget Sound and vicinity

Steller sea lions use Puget Sound as a feeding area from autumn through spring when they are not breeding in British Columbia and Alaska during summer. While the Western Stock of the species is considered Endangered under the US Endangered Species Act (ESA), the Eastern Stock, which occurs in Puget Sound, is increasing in numbers and not listed under the ESA.

Image of two California sea lions sitting on rocks.
9/20/2023

California sea lions in Puget Sound and vicinity

California sea lions have become common in Puget Sound in non-summer months. The overall trend for the population has been a dramatic increase in numbers since the species was protected in 1972. They are opportunistic feeders that often target herring and juvenile salmon and steelhead species in Puget Sound.

A humpback whale seen breaching with more than half of its body out of the water. Land with bare cliff and trees in the background.
9/11/2023

Humpback whales find their voice

The Salish Sea may be a giant ‘practice room’ for humpback whales as they get ready to sing in their winter breeding grounds in Hawaii and Mexico. A network of hydrophones is recording it all.

Cover of 2022 Salish Sea toxics monitoring synthesis: A selection of research
9/1/2023

2022 Salish Sea toxics monitoring synthesis: A selection of research

A 2023 report from the Puget Sound Ecosystem Monitoring Program presents an overview of selected recent monitoring and research activities focused on toxic contaminants in the Salish Sea. 

Adult breeding rhinoceros auklet (Cerorhinca monocerata). Photo: Frostnip (CC BY-NC 2.0)
8/29/2023

A tale of two islands

Were the islands half full of auklets or were they half empty? One scientist offers an insider's view of a newly published study of two Pacific seabird colonies. He says having good data for the paper was key, but finding the right title didn't hurt.

8/4/2023

Dispatch from the last colony

Tufted puffins have become an increasingly rare sight in the Pacific Northwest. Biologist and writer Eric Wagner recently visited Puget Sound's Smith Island, home to one of the region's last surviving colonies of these colorful seabirds. 

The “unstructured grid” used in the Salish Sea Model allows for greater resolution (smaller triangles) when studying complex water circulation, such as around the Hood Canal bridge. Graphic: Tarang Khangaonkar
8/2/2023

Salish Sea Model tracks pollution, currents and climate change

This article is the latest in a series about computer models and their uses within the Puget Sound ecosystem. Today, we look at the Salish Sea Model, one of several models in the region helping to predict water circulation, water quality and food-web relationships.

Book cover
7/16/2023

'A Field Guide to Fishes of the Salish Sea' (book review)

A new field guide brings together detailed accounts and illustrations of 260 species of fish known to occur in the Salish Sea. This review from EoPS editorial board member Joe Gaydos was originally published on the SeaDoc Society website. 

Report cover
7/14/2023

Eyes Over Puget Sound: Surface Conditions Report - June 2023

In June we observed a widespread Noctiluca bloom in Central Puget Sound, evident by bright orange streaks in the water. Noctiluca blooms in Puget Sound have lasted much longer and occurred on a much larger scale than in previous years.

Report cover
7/14/2023

Synthesis of selected NEP Watershed Lead Organization grants administered by the Department of Ecology part 2

A 2023 report from the University of Washington Puget Sound Institute synthesizes past Watershed Lead Organization Program grants to support the EPA-funded Land Development and Cover and Floodplains and Estuaries Implementation Strategies. The report offers lessons learned from the habitat restoration and land acquisition-focused grants.

Weather map of the northwestern United States.
6/29/2023

Six things that people should know about ecosystem modeling and virtual experiments

It’s hard to overstate the importance of mathematical models to science. Models show how planets move and how diseases spread. They track the paths of hurricanes and the future of climate change. Models allow scientists to look at systems or scenarios that they could never view otherwise. Increasingly, mathematical models are also helping scientists understand Puget Sound. In this series of articles, we look at some of the ways that models are being used in ecosystem recovery efforts. We start with the basics. What are mathematical models and which types are most common?

A physcial model of Puget Sound shown without water.
6/28/2023

Before supercomputers, a structural model helped scientists predict currents in Puget Sound

One of the first working models of Puget Sound was a scaled-down concrete reproduction, with actual water running through channels, around islands and into bays, inlets, and harbors. Motors, pumps and timing gears are part of an elaborate mechanism that replicates tides and river flows in the still-functioning model.

Hand holding an oyster.
6/27/2023

Researchers use a qualitative network model to test ways to boost production at shellfish farms

The skeletal beginnings of nearly all models is a conceptual understanding of the basic workings of the system being studied: Who are the important actors, and what are their roles within the system?

Several killer whales swimming with the Seattle skyline in the background.
6/26/2023

Health of killer whales examined through Bayesian network modeling and informed predictions

Many types of computer models are helping researchers study the health of Puget Sound. Bayesian network models are used to examine the probabilities that certain actions will take place within the ecosystem.

Find more articles