Puget Sound Institute

Just after this week's southern resident orca census news, here's another look at these endangered whales — this time, after dark.

"There's no rest for these endangered whales. They are attempting to find food day and night."

That's NOAA Fisheries Service biologist Marla Holt, describing new research that offers the first published look at what southern resident killer whales do after dark. Researchers attached acoustic recording tags to 10 whales and found they're diving and hunting almost as much at night as during the day.
But not evenly. Females are far less likely to attempt a catch at night than during the day, and the drop-off is stark: on deep dives, females had an 88% probability of attempting a catch during the day, but just 21% at night. The findings add to earlier evidence that vessel noise disrupts female foraging more than males' during the day, reinforcing the case for measures that reduce daytime vessel traffic noise in the Salish Sea.

Full story, video of a tagging in action, and audio of orca echolocation clicks: https://tinyurl.com/orcasatnight

Southern resident orca population up by two? Pending one final check, it appears that this year’s census of the endangered southern resident killer whale population will show a positive increase of two orcas — an annual increase equaled only four times in the past 20 years. Check out Salish Sea Currents to learn more about results of the annual orca census conducted by the Center for Whale Research.

https://www.eopugetsound.org/article/annual-census-could-show-increase-two-killer-whales-among-southern-residents

Untangling chemical names and looking back over 200 years of 6PPD history

The tire chemical 6PPD is known worldwide for its deadly effect on salmon, but it also has a complex history. Our senior writer Christopher Dunagan looks back at the chemical's origins, from its connection to a life-saving malaria drug to its ever-present use as a rubber preservative.

https://www.eopugetsound.org/article/history-and-chemical-structure-tire-chemical-6ppd-q

New on the PSI blog: environmental social science — the study of how people and ecosystems shape each other — has quietly built out major infrastructure in Puget Sound over the past decade-plus, from the Human Wellbeing Vital Signs to a Social Sciences Advisory Committee running since 2010. A new introduction to a special issue of Coastal Management, co-authored by PSI's Rob Anderson and Allison Morgan along with twelve others, argues the field has outgrown its "helpful but secondary" reputation and makes the case for treating it as essential to ecosystem recovery. As Anderson puts it, most environmental issues are as much about people and politics as they are about nature itself.

With a worldwide market valuation somewhere around $1 billion a year for the single chemical 6PPD, tire companies and their chemical suppliers are working overtime to find a safe and effective replacement for the toxic tire additive. Our senior writer Christopher Dunagan reports on which companies are in the hunt.

Players in the race for 6PPD alternatives | Encyclopedia of Puget Sound With a worldwide market valuation somewhere around $1 billion a year for the single chemical 6PPD, tire companies and their chemical suppliers are working overtime to find a safe and effective replacement for the tire additive. The financial stakes are enormous, since virtually every tire on the mar...

The northern right whale dolphin is one of the most unusual marine mammals of the North Pacific Ocean and it can sometimes be spotted in the Salish Sea. It is one of only two dolphin species in the world without a dorsal fin, and its slender and streamlined shape make it appear almost eel-like. We have published a new overview of this species in the Encyclopedia of Puget Sound. https://www.eopugetsound.org/article/northern-right-whale-dolphins-salish-sea

Hatchery production is a key tool for supporting vulnerable Pacific salmon stocks, but it comes with tradeoffs. When salmon reproduce in artificial versus natural habitats, different environments can select for different traits — and those genetic effects may carry long-term fitness costs for integrated stocks.

Join Tim Healy of Fisheries and Oceans Canada at the next Salish Sea Science Roundtable to learn about recent findings from the Pacific Salmon Strategy Initiative on heritable effects of hatchery production in British Columbia.

Tuesday, June 30 | 12:30 – 1:30 pm
Free. Registration required. https://tinyurl.com/June30-SSSR

Tire companies race to replace deadly tire chemical

A chemical found in tires is leading to the deaths of untold numbers of coho salmon in Puget Sound every year. Chemical companies are searching for an alternative but say the unique chemistry and function of 6PPD are major challenges. We take an in-depth look at the latest efforts to find a solution. Read the article in our magazine Salish Sea Currents. https://www.eopugetsound.org/article/tire-companies-race-replace-deadly-tire-chemical

Sea lion season in Ballard is winding down, but California and Steller sea lions are still hauled out at Shilshole Marina's boat lift dock (Dock X). Their presence may be no accident. Herring restoration efforts in Central Puget Sound, led by the Suquamish Tribe, are showing signs of success — and the sea lions appear to be following the fish.
Learn more about the sea lions and other mammals of the Salish Sea: eopugetsound.org/species/marine-mammals

PSI's Michael Kern will be team teaching a course on Collaborative Leadership with Zoe Barsness of the UW Tacoma Milgard School of Business as part of the Collaborative Leadership Program at the UW Puget Sound Institute.

The course is open to both undergraduates and graduates as well as non-matriculated students; will provide public, private, and civic sector perspectives on Puget Sound protection and restoration; and offers an opportunity to earn four or five credits in just one month over three in-person Saturdays and three online Tuesday evenings.

If you are interested, or can help spread the word, please check out and/or repost the info below.

Develop your collaborative leadership skills this summer!
The Milgard School of Business is offering T BUS 490/TBUS 590 Collaborative Leadership during Summer Session A (June 22–July 22, 2026).

This hybrid course explores the theory and practice of leading across organizational, cultural, and political boundaries. Through case studies, guest speakers, and applied group projects, you'll learn how Puget Sound and Pacific Northwest leaders address complex environmental and natural resource management challenges.

Course Details:
📅 June 22–July 22
🖥️ Remote: Tuesday evenings
🏫 In-person: Saturdays (June 23, 27, 29 and July 11, 14, 18)
⏰ Enrollment deadline: Friday, June 19

Whether you work in public, private, nonprofit, or tribal sectors—or aspire to—this course will equip you to build and sustain effective cross-sector partnerships and drive collective impact.

Access students are also welcome!
Learn more: https://www.pugetsoundinstitute.org/collaboration/collaborative-leadership-program/