The Guardians of the Kelp Forests

Along California’s rugged North Coast, an uncommon alliance — including scientists, tribal leaders, fisherman, divers, kayakers and seafood chefs — has joined forces with a common goal: To protect California’s vanishing kelp forests before it’s too late

A diver conducts an underwater survey in one of California’s once vast kelp forests, where climate change and other environmental stressors have combined in a “perfect storm” to spell disaster for kelp ecosystems in recent years — Photo by National Park Service

• Linked to climate change, a persistent marine heat wave, known locally as “The Blob,” has contributed to a mass die-off along California’s coast, where more than 90 percent of kelp forests have disappeared since 2014
• Exploding populations of purple sea urchins, which voraciously feed off kelp —yet are delicious for humans to eat — are contributing to the kelp’s demise. So local chefs are cooking up ways to entice Americans to eat more urchins
• Local divers have seen once-prized red abalone all but disappear, so they’ve joined in on kelp forest surveys, turning into citizen scientists and supplying valuable data
• Tribal leaders offer indigenous wisdom to inform ecology and help restore balance
• Recolonizing endangered California sea otters — a keystone species that once thrived along coastal waters before being hunted to near extinction — could be critical to restoring balance to kelp forests

A kelp survey team prepares to embark from Noyo harbor. Photo by California Department of Fish and Wildlife

Noyo Harbor, Fort Bragg, California — This picturesque and stunningly remote coastal Mendocino County town has served as the back-drop for Hollywood movies. Goldie Hawn and Kurt Russell once sailed off into a foggy surf together from this harbor in the 1987 romantic comedy, Overboard.

But these days, people in Noyo have far more brooding concerns on their minds. In waters that many locals depend on for their livelihood, where indigenous tribes once fished for millennia, the kelp forests have nearly disappeared.

Noyo is the jumping-off point in a desperate race to protect the kelp as an ecological disaster looms.

Marine biologists often refer to kelp as the oceans forests. And just like forests on land, the three-dimensional world of kelp supports more species of marine plants and animals than any other ecosystem in the ocean.

But lately, something is clear-cutting the kelp forests, and scientists are worried.

Rising sea surface temperatures sound alarm bells

“The Blob” — shown in this NASA image from August 2019 — is an unusually persistent pattern in the Northeastern Pacific Ocean that scientists refer to as a marine heat wave where sea-surface temperatures have risen by more than 2 degrees Celsius (shown in red).

The recent warming of our oceans is a global phenomenon. Oceans cover two-thirds of the Earth’s surface, and, as CO2 levels rise in the atmosphere, they represent the world’s largest source of absorption of these heat-trapping greenhouse gas.

Along California’s North Coast, “The Blob” has triggered an interlocking chain of impacts, including persistent high pressure areas off our coast, a weather pattern that’s linked to longer and more severe droughts in recent years. Warmer waters have shifted prevailing winds offshore, away from the coast. These winds usually push warmer water further out to sea and away from the coast. Additionally, warmer waters have interrupted normal weather patterns, resulting in less summer fog — upon which so many of California’s rich and diverse ecosystems depend, from kelp to old growth redwoods to California’s famed wine industry.

Since 2014, and again with a re-appearance in 2019, “The Blob” has contributed to the decline of kelp forests up and down the California Coast, from the Channel Islands off Southern California, to Monterey Bay and Carmel, to the San Francisco Bay Area, to the North Coast and further north to the Oregon border.

Upwelling Disrupted — Kelp Forests depend on cool, nutrient-rich upwelling for their survival, but “The Blob” is upsetting this natural cycle

All of California’s four dominant species of kelp — bull kelp, giant kelp, feather boa kelp and the southern species of bull kelp (all of which are forms of brown and green algae, rather than plants)— thrive on rocky surfaces in relatively cool waters. In fact, a majority of marine life off our coasts is sustained by currents of cool waters that curve upward from deep beneath the Pacific Ocean when they push into the continental shelf — a process known as upwelling.

Like forests on land, such as California’s great redwoods, kelp forests act like the ocean’s lungs. They help absorb greenhouse-producing CO2 and sequester carbon back into the natural cycle.

Coastal upwelling feeds California’s rich marine habitats, including the kelp forests. Deep ocean currents, filled with life-sustaining nutrients like plankton and algae, bring cool waters to the surface along the Pacific coast. Normally, these cooler currents are helped by prevailing winds and seasonal oscillation of ocean currents that push warmer water at the surface away from the coast and further out to sea. But anomalies caused by climate change have disrupted this pattern, and much warmer waters at the surface have spelled disaster for kelp forests. Illustration credit: Fiona Morris

The Crash —once great forests “turned into a desert” in a matter of five years

Up and down the coast, the story is the same: massive declines of once vast kelp sanctuaries — an event so devastating, so fast and widespread that scientists are both puzzled and alarmed. The visuals below have become so widely distributed among concerned citizens along the Mendocino coast that they’ve become permanently etched into collective consciousness.

Kelp Sanctuaries Decimated— Comparisons showing kelp cover based on aerial surveys at study sites deemed “kelp sanctuaries” along the Mendocino and Sonoma coasts from 2008 to 2016. Image created from data collected by California Department of Fish and Wildlife and referenced by multiple sources.

The view from Noyo Center — based on aerial observation, comparisons of kelp forest surveys at three kelp sanctuary sites along the Mendocino coast, including Caspar, Noyo and Albion, reveal the extent of the decimation of the once vast kelp forests since 2008.

Before And After — Contrasting views of the surface canopy of a bull kelp forest from a survey site at Ocean Cove on the Sonoma coast, south of Mendocino. The view on the left is from 2012. The same survey site is viewed on the right in 2016. Photos by California Department of Fish and Wildlife, Kevin Joe and Cynthia Catton

Kelp forest ecosystems: restorative interventions to tip toward balance

Regaining a Foot-hold — Images from NOAA show a kelp forest ravaged by purple sea urchins on the left. A restored area on the right shows bull kelp and giant kelp free of purple sea urchins gaining a foot-hold once again.

Scientists point to success to help sustain the kelp by planting reproductive spores so vital to the kelp’s natural regenerate processes.

According to recent research by scientists at UC Santa Barbara and UC Santa Cruz, kelp forests exhibit a surprising resilience when it comes to regeneration, especially when spores are seeded near existing healthy forests. Scientists now have a better understanding of how a healthy kelp forest can benefit other forests hundreds of miles away.

On the Mendocino coast, the guardians of the kelp forests believe this new understanding of kelp resilience will help kick-start kelp regeneration to provide these once great forests with a fighting chance against environmental stressors like purple sea urchins and rising temperatures from climate change.

Helping Kelp Reproduction Along — kelp reproduce through spores that can travel for hundreds of miles. And scientists have discovered how planting kelp spores near existing healthy kelp forests can have positive effects to help restore stressed kelp forests located miles away. (Image is open source)

Kelp’s Major Role in Carbon Sequestration

Because of its rapid growth and photosynthesis, kelp sequesters 20 times more carbon dioxide than land forests, according to scientific studies. With the demise of California’s vast kelp forests, we may lose a vital resource to impede climate change, according to the Intergovernmental Panel on Climate Change.

Kelp is also naturally regenerative. The coming of winter brings storms that dislodge long strands of kelp blades from their their anchoring holdfasts, causing huge clumps of kelp to wash up onshore and drift out to sea. In summer and into early fall, kelp undergoes its major growth cycle when forests can grow up to two feet per day.

Kelp’s Carbon Sequestration Engine — Scientists have begun to build better models to understand kelp’s vital role in carbon sequestration. They’ve measured the food intake of deep-sea crustaceans to get a better understanding of how macroalgae species like kelp end up in deep waters far from where it grows. Illustration by Krause-Jensen and Duarte, Harvard University

Purple Sea Urchins — voracious pests to the kelp, delicious cuisine to humans

Purple sea urchins love kelp forests. They eat everything, including the spores that kelp use to reproduce during their spawning season in mid- to late-fall, before the coming of winter storms.

Starfish prey on purple sea urchins. But star fish have suffered the same demise as the kelp due to the heat wave known as “The Blob.”

Scientists point to sea urchin removal as one way to help restore the kelp forest ecosystem.

Meanwhile, local chefs are joining efforts to remove purple sea urchins, creating a new source of sustainable seafood in the process. They hope to both cook up new savory dishes and benefit the environment.

Voracious eaters — a cluster of purple sea urchins where population explosion has gone unchecked — known as a barren — results in a rapid decline of kelp forests, as the urchins devour the kelp en masse. Scientists who study kelp forests restoration have found that there’s a tipping point within kelp sanctuaries, where the explosion purple sea urchins reaches such an extent that sustaining kelp ecosystems becomes more difficult.

Sustainable Seafood — Local chefs want you to enjoy the exotic taste of uni

The profusion of purple sea urchins along Mendocino’s coast spells opportunity for local chefs, who are devising delectable dishes as the latest form of sustainable seafood.

Catch Of The Day — Local chefs are donning wetsuits to gather now-plentiful purple sea urchins, combating an environmental crisis and helping the kelp forests in the process. Photo by Jason Jacks.

Local Chefs turn Beachcombers — with the rising population of purple sea urchins along the Mendocino Coast, local chefs have become expert beachcombers. They hope the palates of Americans will adapt to the taste of uni, which comes from the urchin’s reproductive organs, found by cracking open its soft surrounding shell. Photo by Maria Finn.

Notes of Sea Salt and French Butter — An uni appetizer served on glazed heirloom potato. Local chefs anticipate that Americans will get accustomed to the raw taste of purple sea urchin — and savor the new dish as part of the sustainable seafood movement.

Divers, kayakers and beachcombers enlisted as Citizen Scientists

The urgency facing the kelp has drawn a growing number of concerned citizens to Mendocino. The campaign to protect kelp habitat brings together the skills, knowledge and expertise of fisherman and nature lovers alike.

Armed with smartphones and camera-laden drones, outdoor enthusiasts are teaming up with ecologists to help protect the kelp.

Local organizations like Reef Check help by training and certifying divers, kayakers, boaters and surfers. They run surveys that supply scientific data on sea surface temperature, salinity, pH, oxygen content, wave activity, and other oceanographic conditions relevant to kelp habitats.

Technology-assisted citizen science — Red abalone divers measure, weigh and photograph their catch, supplying scientists with valuable data from the field. (Image source: Nature Conservancy and David Hills Photography)

Citizen Science Joins the Cause— Locals help with a sea urchin round-up: purple sea urchin removal helps restore balance to kelp forest ecosystems. These volunteers weigh, measure, identify and sort each day’s catch. Fewer sea urchins devouring kelp gives the kelp a fighting chance for survival. Photo my Michelle Blackwell, Mendocino Beacon.

Re-Homing the California Sea Otter to restore ecosystem balance

One way to restore balance to the kelp forests is to bring back the California sea otter, a natural predator species that thrives by eating massive amounts of purple sea urchins in kelp forests.

As a keystone species, sea otters help maintain ecological balance by preying on purple sea urchins that devour the kelp.

Scientists at Sonoma State University believe they can restore the same species of sea otter that once thrived in Northern California before they were hunted to near-extinction in the 1800s.

Scientists are encouraged by a come-back that populations of sea otters have made in recent years, especially in San Francisco Bay and along California’s Central Coast.

Indigenous voices inform kelp science

Scientists have turned to tribal representatives to apply their vested and wide-angled perspectives to help mitigate kelp deforestation. Tribal leaders now occupy important roles in the educational and advocacy process, including representation on advisory boards like the Greater Farallons Association and as docents as the Noyo Center.

On June 18, 2019, California Governor Gavin Newsom signed Executive Order number 15–19 which extended an official apology for past atrocities and injustices committed against native peoples across California.

The governor’s gesture is largely symbolic and doesn’t change history. But it does signal an important first step toward increasing tribal representation and amplifying the voices of indigenous peoples as we face unprecedented climate change, species extinction, and environmental decline.

As these issues continue to make headline news, indigenous perspectives and practices are emerging as critical resources that amplify scientific efforts and environmental advocacy.

Resources, Places to Go, and Ways to Get Involved

Kelp Forests — Background Research

Plenty has been written and is readily available about California’s kelp forests. Here’s my selection of the best resources I could find:

• Video: Ecosystems of California — Kelp forests — by professor Erika Zavaleta, University of California Santa Cruz, December 7, 2015
• Report: Sonoma-Mendocino Bull Kelp Recovery Plan, published by the Greater Farallons National Marine Sanctuary and the California Department of Fish and Wildlife, April 2019
• “California’s Underwater Forests Are Being Eaten by the Cockroaches of the Ocean,” by Kendra Pierre-Louis, New York Times, October 22, 2018
• Scientific Paper: “Marine Heat Wave and multiple stressors tip bull kelp forests to sea urchin barrens,” Nature, Scientific Reports, by L. Rogers-Bennett and C.A. Catton, Coastal Marine Science Institute, Bodega Bay Marine Laboratory, October 21, 2019
• “Bull Kelp restoration funding granted for Mendocino County,” by Michelle Blackwell, Fort Bragg Advocate-News, March 25, 2020
• “California’s Crashing Kelp Forest — How Disease, Warming Waters and Ravenous Sea Urchins Combined to Kill the Kelp and Close the Red Abalone Fishery,” by Kate Kerlin, UC Davis, October 21, 2019
• “Getting by with a little help from their friends,” by Julie Cohen, University of California at Santa Barbara, Phys.org, January 25, 2017

“Kelp forests can bounce back from destructive storms when the forests are in reasonably close proximity to healthy beds. In much the same way that the wind scatters plant seeds over the land, ocean currents carry trillions of microscopic spores from one kelp forest to another, where they create life for ailing populations.”

More About “The Blob,” Ocean Warming and the vital role of Kelp in carbon sequestration

• “Climate Change: Ocean Heat Content,” by LuAnn Dahlman and Rebecca Lindsey, NOAA, February 13, 2020

“The ocean is the largest solar energy collector on Earth.” — NOAA

• “Oceans Are Absorbing Almost All of the Globe’s Excess Heat,” by Tim Wallace, New York Times, September 12, 2016
• “New Marine Heat Wave Emerges off West Coast, Resembles “The Blob,” NOAA Fisheries, September 5, 2019
• “How Kelp Naturally Naturally Combats Global Climate Change,” by Sylvia Hurlimann, Harvard University Graduate School of Arts and Sciences, July 4, 2019

California’s Marine Protected Areas — along the North Coast and Beyond

California is fortunate to have a quilt-like network of marine protected areas, including marine parks, reserves, conservation areas, recreational management areas and special closures. This patch-work of protection ensures that habitat remains protected in perpetuity — not just in one place but in multiple locations over the entire span of California’s coastline. This factors especially well for kelp forest protection, as the health of kelp habitat in one location in connected to others miles away. It also helps ensure that efforts for conservation and habitat restoration in one area will have positive impacts in other neighboring areas.

Sea Otter Re-Colonization — the critical importance of Keystone species, trophic cascades and The Green World Hypothesis

• Video — “Some Animals Are More Equal Than Others — Keystone Species and Trophic Cascades,” by HHMI Biointeractive, May 3, 2016

See also accompanying article, “The Ecologist Who Threw Starfish — Robert Paine showed us the surprising importance of predators,” by Sean B. Carroll, Nautilus, Issue 37, June 2, 2016

• “Study finds California could triple Southern Sea Otter population by recolonizing San Francisco Bay,” Sonoma State University, December 9, 2019

Purple Sea Urchins — from marine science to ocean tipping points to sustainable seafood and haute cuisine

• “The Urchin’s Tale — What Have Sea Urchins Taught Us About How Ecosystems Work,” by Natalie Low, Stanford University, November 18, 2016

“One thing that scientists have discovered is that tipping points are different, depending on which direction the ecosystem is tipping. For example, it takes fewer sea urchins to maintain an urchin barren than it does to create one. So to turn an urchin barren back into a kelp forest, we would need to reduce sea urchin populations to a much lower number than if we just wanted to stop a kelp forest from becoming an urchin barren.”

“In other words, it is easier to prevent an ecosystem from ‘tipping over’ into a less productive state than it is to restore an ecosystem that has already crossed that threshold. When it comes to managing ecosystems, prevention is better than cure. These concepts don’t just apply to kelp forests: they are helping us protect and manage a diverse range of ecosystems including coral reefs, estuaries, and grasslands.”

• Scientific Paper: “Geographically Opposing Responses of Sea Urchin Recruitment to Changes in Ocean Climate,” by Daniel K. Okamoto, Daniel C. Reed, and Stephen Schroeter, Florida State University and the Marine Science Institute, University of California at Santa Barbara, August 2018
• “The purple urchins feeding California,” BBC, by Maria Finn, March 10, 2020
• “Urchin Explosion,” by Maria Finn, Edible Marin & Wine Country, February 21, 2019
• “A Plague of Delicious Purple Urchins is Taking Over the California Coast and It’s Our Duty to Eat Them,” by Ali Bouzari, Saveur, June 7, 2018
• “Why we should be eating more purple sea urchins,” The Splendid Table, by Francis Lam and Ali Bouzari, July 26, 2018
• “Saving California’s Kelp Forest May Depend on Eating Purple Sea Urchins,” National Public Radio, member station KAZU-Monterey, by Erika Mahoney, September 9, 2019

Tribal Voices

As environmental impacts increase the likelihood of food insecurity, indigenous peoples are especially hard hit. Yet, their ancient connections to the land and the sea mean that their lives are intimately tied to local sources of food and materials from shell fish and seaweed and the plants and animals that depend on them.

Debra Utacia Krol is a member of the Xolon Salinan tribe of Central California who writes extensively on Native issues in California through her award-winning journalism. The indigenous people of the North Coast are particularly hard-hit by climate change. Yet their ancient wisdom could hold vital solutions and deeper ecological understanding to address our global problems stemming from climate change.

• “An Indigenous way of life for these California tribes breaks state law — In Mendocino, “guerrilla gatherers” risk fines and jail time to keep food culture alive,” by Debra Utacia Krol, High Country News, September 17, 2019
• “A shrinking supply of abalone shells impacts coastal tribes,” by Debra Utacia Krol, High Country News, February 26, 2018

California’s Abalone and Citizen Science in Action

California is home to more species of abalone than anyplace on Earth. For centuries, indigenous peoples were experts in abalone gathering and depended on abalone for their survival. We get the word abalone from the Rumsen peoples, a group of Ohlone who populated the Carmel Valley and Monterey Peninsula . Abalone depend on the kelp forests for their habitat. They feed on algae and scraps of kelp that are broken off and stirred up by the tides.

• Video — “Californians Grapple with the Loss of Red Abalone,” by Peninsula Press and Stanford Journalism, June 9, 2019
• Video — “Dying Oceans — Abalone Restoration in California,” KCETOnline, May 28, 2019
• “Closing the Abalone Data Gap — Can putting technology in the hands of citizen scientists transform how abalone are managed?,” The Nature Conservancy, California Conservation Science Program
• “Reef Check California brings citizen scientists to the North Coast,” by Tristin McHugh, Fort Bragg Advocate-News, October 4, 2018

Centers offering resources for exploration, hands-on learning and citizen scientists

• Noyo Center —two locations, at the Discovery Center in downtown Fort Bragg and the Interpretive Center at Noyo Harbor
• Greater Farallons Association — visitors center located at Crissy Field and offices at the Presidio in San Francisco
• Reef Check — trains and certifies divers, fisherman, kayakers, surfers and boaters as citizen scientists for data collection, monitoring, and site surveys
• Watermen’s Alliance — an active group of recreational divers turned citizen scientists that conducts purple sea urchin removal and other ecological and habitat protection efforts benefiting the kelp forests of Mendocino County
• Frencesca Koe — an expert kelp forest diver, ocean advocate and citizen scientist who has written about kelp forests habitat protection on Medium.

Getting There and Getting Involved

• Trails Galore! — Hiking with the Mendocino Land Trust
• Support — you can support the efforts of The Last Forests Project, a documentary about kelp forests that’s in the works

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