Explore the 2021 Kelp Expedition Storymap Here

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 a valuable coastal habitat in temperate areas throughout the world. Bull kelp, Nereocystis luetkeana, is an iconic foundation species on the West Coast, forming extensive forests in nearshore, rocky habitats. These large, fast-growing kelps create 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, 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 restoration actions called for in the Recovery Plan, with focus on the following 4 of 6 strategic goals identified in the Plan: Restore kelp forests (Goal #5), Describe kelp distribution & trends (Goal #3), Reduce stressors (Goal #1), and Promote awareness, engagement, and action from user groups, Tribes, the public, and decision-makers (Goal #6).

What is bull kelp?

Bull kelp, Nereocystis luetkeana, is an iconic foundation species of the West Coast, forming extensive forests in nearshore, rocky habitats. Characteristics of bull kelp include that it:

Is a Puget Sound floating kelp species, along with giant kelp, found in the Strait of Juan de Fuca and along the coast
Creates a living canopy structure – bulb & blades reach to the surface while a holdfast remains anchored to the hard bottom
Resembles long whips with bulbs on the end
Is an annual algae, so each spring a new generation of kelp emerges and grows to create the forest canopy
Is a fast-growing species that thrives in cool, nutrient rich, high flow waters

Why is kelp canopy important?

Kelp forests are one of the most productive habitats on the planet, functioning as the carbon factories of estuaries. Puget Sound’s diminishing kelp forests provide key habitat for species throughout the marine foodweb. Kelp can grow into massive vegetative structures that feed and shelter numerous species from bacteria to mammals.

Kelp forests are efficient absorbers of carbon dioxide
As the forest grows, it absorbs nutrients, shelters fish, & attenuates storm surges
Throughout its life cycle, kelp feeds salmon, rockfish & invertebrates

Kelp & Climate Change:

Restoring kelp helps address climate change, by sequestering carbon dioxide from the atmosphere
Sequestered carbon dioxide is stored for longer periods of time as it moves through the food web
Bull kelp is vulnerable to warming seawater temperature

Kelp & Humans:

Bull kelp forests have been a fundamental underpinning of life in the Salish Sea for thousands of years
A connected ribbon of kelp forests fringing our nearshore waters has long supported people by providing safe canoe passage & an abundance of food sources.
First Americans followed a kelp-bound coastal route called the kelp highway
The kelp highway delivered a perfect “subsistence package” of marine foods that enabled human travel & later supported settlement

Where has the kelp canopy gone in Puget Sound?

Major ongoing declines in floating kelp abundance have been documented throughout Puget Sound for several decades. The causes of these declines are uncertain. Likely factors include the following stressors and their interactions:

Deterioration of water quality (excess nutrients & sediments), from runoff & shoreline development
Rising seawater temperature
Competition with other seaweeds, including invasive species
Grazing by animals, possibly increased due to shifts in the marine food web caused by fishing or other perturbations

Program component 1: Determine how to restore self-sustaining kelp forests

Experimental kelp outplanting

PSRF is developing restoration practices to recover the natural recruitment of bull kelp on a landscape scale in areas where bull kelp were found historically. Enhancement trials involve seed transfers and other manipulations to learn what works and what doesn’t to facilitate the recovery of bull kelp forests.

We have extensive work off of the Doe-Kag-Wats estuary and Jefferson Head, with support from NOAA and others. In 2020, bull kelp from our pilot-scale enhancement at Doe-Kag-Wats/Jefferson Head reached the surface – an event which has not been observed since the early 1990s. Across the water, at Smith Cove near downtown Seattle, we are part of a three-pronged habitat enhancement project that is part of the Port of Seattle’s Blue Carbon Initiative. In our kelp rebuilding, we focus on three facets:

Observing natural recruitment to both natural and kelp-enhanced substrates;
Investigating the effect of presence of adult bull kelp on recruitment of a second generation; and
Evaluating the spatial gradient of kelp seed dispersal

View the time-lapse video below and the accompanying photos to get a glimpse into how we are testing our enhancement techniques!

Program component 2: Use cultivation to enhance kelp supply

Cultivation at the Kelp Lab

Laboratory facilities at PSRF’s conservation hatchery at NOAA’s Manchester Research Station make it possible for us to research bull kelp propagation, genetics, and other questions about Puget Sound kelps and macroalgae. Our kelp lab is the springboard for our in-water enhancement projects. Further, we have been able to support Washington’s nascent seaweed farming through production of sugar kelp seed for use in research and aquaculture.

Program component 3: Understand kelp ecology in Puget Sound

Index site monitoring

In 2020, PSRF launched an underwater kelp ecological survey program. 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 restoration; our program aims to fill that gap. Our protocol stems from the PISCO survey method and is adapted for the unique conditions of Puget Sound. Initially, PSRF and our partners will survey kelp forests at four index sites in Central Puget Sound, shown on map below. We hope to expand this program to monitor kelp forests Sound-wide, so stay tuned!

On the horizon

A kelp expedition, a seed bank, and more

Kelp restoration is in its infancy. Techniques are still in the development stage and ecological mysteries are legion. PSRF is involved in numerous exciting collaborative projects, with more to surely come – reach out to us if you are interested in collaborating on this great work!

Kelp Expedition 2021. We successfully launched a science-based expedition in July 2021 to visit rich forests and shine a spotlight on the importance of kelp as a marine foundation species throughout Puget Sound. On this expedition, we:

Highlighted healthy kelp forests;
Engaged new partners in restoring kelp forests; and
Collected samples, such as propagules for our bull kelp seed bank, and data, including various metrics of biodiversity.

Explore the storymap that covers the Expedition and more here!

Bull kelp seed bank. In the immediate future, we will create a library of kelp gametophytes for cultivation, genetic analysis, and restoration projects, using the kelp lab at our conservation hatchery – the Kenneth K. Chew Center for Shellfish Research and Restoration.

Genetic structure of bull kelp. Filipe Alberto’s Lab at the University of Wisconsin Milwaukee is leading work, in collaboration with PSRF, to study Puget Sound bull kelp genetics, drawing on their work with giant kelp. As the work proceeds, goals include to: