Kelp Needs Your Help

Scientists and community members are working to monitor and restore bull kelp within the Salish Sea.

Up close picture of the buoyant top anatomy of a bull kelp plant called a pneumatocyst. // Photo by Hannah Gabirelson

Story by Phoebe Clark

June 13, 2024

When many picture a forest, they think of towering trees stretching towards the sky. But there's another kind of forest. These also reach for the sun and, like tree forests, serve as the cornerstone of a diverse and complex ecosystem. Yet, they are concealed beneath the ocean's surface.

These are bull kelp forests.

Throughout the Salish Sea, an inland sea connected to the Pacific ocean stretching from Seattle, WA to Vancouver, B.C., bull kelp forests are disappearing. More than half of the Salish Sea’s bull kelp have died in the past 145 years. 

Kelp Rescue Initiative researcher monitoring the seeded line array bull kelp site near Hornby Island. // Photo courtesy of The Kelp Rescue Initiative, photo by Rebecca Benjamin-Carey

Climate change, particularly rising ocean temperatures, poses one of the most significant threats to bull kelp throughout the Salish Sea. Bull kelp thrive in cold water. In warmer water, kelp consume less dissolved oxygen and cannot take up as many nutrients as they do in cold water. 

In recent years, rising ocean temperatures have made it harder and harder for bull kelp forests to thrive. This poses a threat to the overall health of the Salish Sea.

Bull kelp is a keystone species within the Salish Sea, meaning that its presence plays an important role in maintaining the health of many species within the ecosystem. 

More than 1,000 species rely on bull kelp’s unique subsurface canopy, which can reach heights of up to 100 feet and create habitat from the seafloor to the water's surface. Many of these animals, like salmon, rockfish, orcas and blue herons, play pivotal economic and cultural roles throughout the region. 

Bull kelp hold profound significance for the Salish people, who often relied on vast kelp forests for sustenance as they traveled along the Pacific coast. Kelp appears in folklore and parables, and was often used as toys, target practice and musical instruments. 

Kelp supports the fishing industry and pulls carbon dioxide out of our environment.

“We all have a connection to kelp forests and they're super important ecosystems,” Lauren Dykman, a postdoctoral fellow and restoration science lead at the University of Victoria and The Kelp Rescue Initiative (KRI), said. “The idea that a kelp forest might not exist in this area anymore is really alarming.” 

Nearly a thousand species rely on the ecosystem of a bull kelp forest habitat, including several of the main species depicted above. // Graphic by Emily Grund.

Dykman has been conducting research projects to determine the optimal approach for bull kelp restoration efforts. As ocean temperatures rise and ocean heat waves become more frequent, bull kelp forest restoration will become more of a necessity. 

A study conducted last year at a kelp farm in the Strait of Georgia near Hornby Island took genetically varied bull kelp from across the Salish Sea. Some were from more distant, cooler sites while others were from warmer, closer sites. Each acted differently at the kelp farm. Kelp from cooler water grew for a longer period of time, whereas warmer-climate kelp had longer blades. 

The KRI chose this testing site because of a partnership forged with a local, family-owned dive shop, Hornby Island Diving. The dive shop has been cultivating a kelp farm on seeded line arrays to expand marine habitat because of the disappearance of a large bull kelp forest in that area. 

The study found that kelp bed managers might find more success by seeding a wide variety of kelp, from all types of ocean temperatures and locations. The study also acts as a baseline for organizations across the Salish Sea working on restoration projects. South of Hornby Island, the Puget Sound Restoration Fund (PSRF) is another group  working to restore bull kelp.

“We grow kelp from seed and we put it on some kind of infrastructure on the seafloor to see if we can recreate a kelp bed or kelp forest there,” Hillary Hayford, research director of the PSRF, said.

A kelp bed near Jefferson Head in the Hood Canal offers a glimmer of hope amid PSRF’s restoration projects. Hayford recently discovered that 14 new bull kelp have naturally grown underneath their man-made forest.

“That's something we've been trying for a really long time,” Hayford said.

Citizen volunteer in the kayak monitoring program measuring the depth of a bull kelp forest. // Photo by Rich Yukobousky

Community action can also drive bull kelp restoration. The Northwest Straits Commission (NSC) has created a kayak monitoring program that enlists the help of local community members across seven counties in the Northern Puget Sound. 

Each county has an appointed Marine Resource Committee (MRC) that establishes and organizes the prominent issues and priorities related to the marine environment. The MRC oversees the bull kelp kayak monitoring program in each county. Their objective is to collect data about the health and fluctuations of the remaining bull kelp beds in the Puget Sound.

"The program started small, sampling just one site with volunteers from the Whatcom MRC, and grew to six sites with many more volunteers,” Eleanor Hines, previous Whatcom MRC and North Sound Baykeeper lead scientist at RE Sources for Sustainable Communities, said.

Since 2016, Hines has been kayaking around Whatcom County, leading three to four volunteers on data collection missions. A cool salty breeze beckons them onward as they use handheld GPS devices to map the boundaries of the kelp beds. They also collect data like water temperature and estimations of bed depth. This information offers valuable insights into the condition of bull kelp along the shoreline.

The data is placed in a database that is accessible to other restoration and research organizations like the KRI and the PSRF. 

Since the start of the monitoring program in Whatcom county, the kelp beds have seen slight decreases in diameter but their overall health hasn’t changed, according to Hines. 

Hopefully, with the continued help of the community and scientists, these underwater forests will stay resilient in the face of climate change. 

Lush bull kelp forest in the Salish Sea. //Photo by Hannah Gabrielson

Phoebe Clark is an environmental studies major investigating the relationships between humans and the environment.