Our goal is to reverse declines of Puget Sound kelp forests and develop solutions to rebuild the essential habitat kelp forests provide.

Kelp forests are some of the most diverse and productive ecosystems in temperate seas around the world. On the west coast, Bull kelp (Nereocystis luetkeana) is an iconic foundation species, forming extensive forests in rocky nearshore habitats. These large, fast-growing kelps provide forage and refuge habitat for a diversity of marine life, contributing greatly to the productivity and biodiversity of coastal marine ecosystems.

In 2020, Puget Sound Restoration Fund (PSRF), in partnership with several government agencies and nonprofits, developed the Puget Sound Kelp Conservation and Recovery Plan. This plan envisions a revitalized bull kelp population in Puget Sound, and outlines a path for getting there.

PSRF is spearheading several key actions from the Recovery Plan, with a focus on four of its six strategic goals: Restore kelp forests (Goal #5); Promote awareness, engagement, and action from user groups, Tribes, the public, and decision-makers (Goal #6); Describe kelp distribution & trends (Goal #3); and Reduce stressors (Goal #1).

What is bull kelp?

Bull kelp (Nereocystis luetkeana) is an iconic foundation species of the West Coast, forming extensive forests in nearshore, rocky habitats. Key characteristics include:

Floating algae – Along with giant kelp, bull kelp is one of two floating kelp species found in Puget Sound,the Strait of Juan de Fuca and along the coast.
Creates a living canopy structure – Each plant anchors to hard surfaces with a holdfast while its whip-like stipes grow upward to a buoyant bulb & leafy blades that spread across the surface.
Annual life-cycle – Bull kelp complete its life-cycle in a single year; each spring a new generation emerges and quickly grows into a dense forest canopy.
Fast-growing – In cool, nutrient rich, fast-flowing waters bull kelp can grow up to several inches per day.

Why is kelp canopy important?

Kelp forests are one of the most productive habitats on the planet, functioning as the carbon factories of estuaries. In Puget Sound, where kelp is in decline, these underwater forests provide essential habitat that supports life from the tiniest plankton to forage fish, salmon, to marine mammals.

Benefits of Kelp Forests:

Carbon alchemists – Kelp forests efficiently transform carbon dioxide into biomass.
Habitat and shelter – The dense forests shelter fish and invertebrates during various life stages, from young to old.
Coastal resilience – Kelp forests absorb wave energy, reducing shoreline erosion and buffering storm surge.
Food web support – Throughout its life cycle, kelp feeds salmon, rockfish & invertebrates.

Kelp & Climate Change:

Restoring kelp helps combat climate change, by sequestering carbon dioxide from the atmosphere.
Sequestered carbon dioxide is stored for long periods of time as it moves through the food web.
However, bull kelp is vulnerable to warming seawater.

Kelp & People:

Bull kelp forests have been a fundamental underpinning of life in the Salish Sea for thousands of years. A connected ribbon of kelp forests once fringed our nearshore waters, supporting safe canoe passage, an abundance of food sources, and thriving coastal communities.

Indigenous peoples followed a kelp-bound coastal route called the kelp highway – a life way, delivering a subsistence package of marine foods that enabled human travel, supported settlement and trade.
Today, kelp continues to sustain us – if we care for it! (Tip: follow harvesting rules to help our kelp thrive!)

Where has the kelp canopy gone in Puget Sound?

For decades, scientists, tribes, and community members have documented major declines in bull kelp throughout. Once-dense canopies are now sparse or absent in many areas.

The exact causes are not fully understood, but likely drivers include the following stressors, acting independently or cumulatively:

Declining water quality – Excess nutrients, sediments, and pollution, from runoff and shoreline development can harm kelp growth.
Warming seas – Rising seawater temperature stress kelp, which thrive in cooler water.
Competition – Other seaweeds, including invasive species, compete with kelp for light and space.
Predation – Shifts in the food web may lead to increased grazing by a variety of predators.

PSRF's Kelp Origin Story

PSRF entered the world of kelp originally in 2010, at the suggestion of Leonard Forsman, Chair of the Suquamish Tribe. Leonard remembered fishing trips with his dad off Jefferson Head/Doe Kag Wats estuary as a kid. The kelp bed was thick back then and they used to catch lots of fish. Then the bull kelp vanished, sometime in the 80s or 90s. “You should try to restore it,” he said. Soon after, we started our first tests, working initially with the Suquamish Tribe, the Port Gamble S’Klallam Tribe, the Puget Sound Pilots, and property owners off Restoration Point. We continued testing different methods with Washington Department of Natural Resources and then began working with NOAA. And we are still at it today.

PSRF's Kelp Recovery Program

Kelp restoration is rapidly evolving – techniques are still being refined and retooled, and ecological mysteries are legion. PSRF is at the forefront of this work, leading and collaborating on innovative projects around Puget Sound. Our Bull Kelp Recovery program spans research, restoration, and engagement – both in the lab and the field. From piloting new outplanting methods, to cultivation and seed banking in the lab, we are building partnerships and working towards a Puget Sound filled with thriving kelp forests. Explore some of the many facets of the program below.

Recognizing the Evergreen State’s underwater forests

Designation of Washington’s Official State Marine Forest

With strong support from Tribes, conservation organizations, and local communities, the Washington State Legislature passed House Bill 1631, officially designating bull kelp forests as Washington’s marine forest. The bill was sponsored by Representative Greg Nance and signed into law by Governor Bob Ferguson on April 16, 2025. The law also established April 16, 2025 as Bull Kelp Day in Washington State. This recognizes the ecological, cultural, and economic importance of Bull kelp to our state!

Determining how to restore self-sustaining kelp forests

Experimental kelp outplanting

PSRF is pioneering restoration practices to recover the natural recruitment of bull kelp on a landscape scale in areas where bull kelp were found historically. Our experimental outplanting and enhancement trials involve seed transfers and other techniques to learn what works and what doesn’t to reforest kelp.

In our kelp rebuilding, we focus on three key questions:

Recruitment – How does kelp recruit to both natural and kelp-enhanced substrates?
Generational success – Does the presence of adult bull kelp influence recruitment of a second generation?
Seed Dispersal – What is the spatial gradient of bull kelp seed dispersal?

Jefferson Head / Doe Kag Wats Estuary

PSRF has led extensive work off Jefferson Head and the Doe Kag Wats estuary (JHDKW), with support from NOAA and the Suquamish Tribe. Each year since 2020, bull kelp from our pilot-scale enhancement at JHDKW has grown from seafloor to surface – an event which had not been observed since the early 1990s. Since 2023, we have observed bull kelp recruitment on natural substrate in the area, some of which have reached reproductive maturity, with strong evidence suggesting these are second generation kelp produced from previous years’ outplant.

Once the outplanted kelp reaches the surface at the enhancement site, PSRF transitions to surface monitoring surveys, collecting morphometric data to track the growth rate, reproductivity, biomass, and longevity of the kelp bed. For comparison, we also survey wild bull kelp forests at Magnolia (our geographical comparison site) and North Beach (our source population site).

Collaborative Projects

PSRF collaborates with a multitude of Tribes, agencies and organizations across Puget Sound on bull kelp projects, including:

Port of Seattle:(2018-2023) As part of the Port of Seattle’s Blue Carbon Initiative, PSRF tested substrate enhancement and seeding efforts to increase macroalgal diversity in Smith Cove in Elliott Bay.
Squaxin Island Tribe: (2023-present) PSRF began actively working with the Squaxin Island Tribe to conserve and restore their local bull kelp forest – the southernmost remaining kelp forest in Puget Sound. Building from PSRF’s experimental outplant design and knowledge base, as well as the Tribe’s Traditional Ecological Knowledge, juvenile bull kelp have been planted at a site near the existing kelp forest, in an attempt to gain greater understanding on the challenging conditions that kelp in southern Puget Sound face, as well as bolster the number of kelp growing in the area.
Samish Indian Nation: (Since 2024) PSRF has been collaborating with the Samish Indian Nation to develop a bull kelp outplant site at a targeted culturally significant location (or something like this)… emphasizing that we are contributing our practical knowledge but they are running the show.*****

Community engagement in kelp restoration and monitoring

Kelp Gardening

Thanks to funding from the Washington State Legislature, Builders Initiative, and Bainbridge Community Foundation, PSRF is piloting a new approach to recover kelp forests in Puget Sound by engaging our local community in hands-on, restoration actions.

We’re testing innovative techniques to disperse locally sourced bull kelp in priority sub-tidal areas. Our ‘light touch’ approach does not require permits (per discussions with DNR/WDFW), utilizing locally sourced genetic material as well as biodegradable materials deployed on existing in-water structures and substrates to avoid introduction of permanent or foreign gear.

We’re calling upon tideland owners and/or kelp enthusiasts to help us access and deploy kelp seed around Bainbridge Island, and monitor each site in order to understand the effectiveness of these experimental techniques and their potential role in Sound-wide recovery efforts.

Read more about our community-driven Kelp Gardening project! (include link to new dedicated page)***

Join us in our quest for bull kelp in Washington!

iNaturalist- Kelp Spot

In 2025, PSRF launched Kelp Spot, a community science project on iNaturalist. The goal is simple but powerful: to engage the public in tracking bull kelp by mapping observations across time and locations throughout our region.

Every sighting matters. Community-submitted observations offer valuable, real-time insights into bull kelp presence, density, and seasonal persistence at various sites across Washington’s marine waters.

Interested in contributing or learning more about the project? Visit [HERE].

Using cultivation to enhance kelp supply

Cultivation and Seed Banking at the Kelp Lab

At PSRF’s conservation hatchery, located at NOAA’s Manchester Research Station, our laboratory facilities allow us to study bull kelp propagation, genetics, and other questions about Puget Sound kelps and macroalgae. Our kelp lab is both a research hub and the springboard for our in-water enhancement projects.

Since 2023, the lab has been home to Washington’s first bull kelp seed bank, developed in close collaboration with Dr. Filipe Alberto’s Lab at the University of Wisconsin Milwaukee. The bank currently contains material from 29 bull kelp collections made throughout the southern Salish Sea, with more collections added each year.

The seed bank holds essential source material to produce seed for kelp restoration now and into the future. It also allows us to conserve genetic material in perpetuity should local beds disappear. In the kelp lab, we have also produced sugar kelp seed for use in both research and aquaculture.

Want to dive deeper? Explore our Kelp Cultivation Handbook for an inside look at the techniques behind our work.

Understanding kelp ecology in Puget Sound

Index site monitoring

In 2020, PSRF launched an underwater kelp ecological survey program to address critical data gaps. While kelp forests are well-studied in open coastal environments, long-term underwater ecological studies of kelp forests in Puget Sound have been limited. This gap in ecological knowledge presents a serious roadblock to recovery; our program aims to fill that gap.

In 2022, PSRF was a major partner in facilitating Reef Check Foundation’s expansion of their Kelp Forest Program into Washington State. Reef Check Kelp Forest Monitoring protocols stem from the PISCO survey method, but have been specifically adapted for the unique conditions and biological communities of Puget Sound.

Additionally in 2022, we scaled up in a big way, with the launch of the Eyes on Kelp Initiative. Through this comprehensive kelp forest monitoring initiative, PSRF established a network of 14 underwater kelp monitoring sites, pairing ecological surveys with an array of environmental instruments. This work was made possible with our powerhouse partners Reef Check Foundation, Marauder Robotics, and The Bay Foundation, as well as expanded partnerships with Tribal Nations, resource agencies and local communities, with support from the Paul G. Allen Family Foundation.

Spotlighting Kelp

A Kelp Expedition to Collectively Highlight our Marine Forests

In July 2021, more than 180 participants from 40+ partner organizations came together for the first modern-day Kelp Expedition in the waters of the southern Salish Sea. Over eight days, the Expedition brought people out on the water to see kelp forests up close, breathe life into the Kelp Plan and catalyze a movement to protect and restore our marine forests.

The Expedition served to spotlight the importance of kelp forests, showcase coordinated actions across Tribes, agencies, NGOs and researchers, facilitate collaborative science and research to fill information gaps, share knowledge about kelp forests, and celebrate the role kelp forests play in communities throughout Puget Sound.

Explore more from the Expedition: