Oregon’s underwater forests are vanishing. Can they be saved?
On a chilly May morning at a sandy beach 15 miles southwest of Coos Bay, marine ecologist Sara Hamilton poured hot water from a thermos into her thick wetsuit, neoprene dive boots and gloves. Snorkeling mask and fins in hand, she made her way toward the jutting headland of Cape Arago State Park, across slippery rocks draped in seaweed, mussels and barnacles and crevices teeming with green sea anemones.Hamilton eased herself into the ocean, a frigid 49 degrees that day, followed by several colleagues who braced themselves on surf-drenched rocks. But the waves crashed too high, sending the team into shallower waters before they floated and dove down.A lush, towering kelp forest had sprung up under the waves in this cove in each of the past three summers, providing refuge to juvenile rockfish and salmon, shrimp, whales and countless other creatures. But it was unclear if it would regrow this year or become the latest casualty of an upended marine ecosystem that could herald the future impact of global warming on Oregon’s coast.For millennia, underwater forests of seaweed or large brown algae stretched from the seafloor to the ocean’s surface, forming canopies, much like trees, and providing food, shelter and hunting grounds to countless animals. Bull kelp, the predominant species found along the southern third of Oregon shores, is one of the world’s fastest growers – rising at a rate of up to 10 inches per day and reaching heights of up to about 100 feet, establishing itself as the sequoia of the seas. Kelp has helped protect the coastline from storms and supported local fisheries, tribal fishing and cultural practices.But over the past decade, according to new data, Oregon lost more than two-thirds of that kelp canopy.Kelp’s troubles on the West Coast started in 2013 when a mysterious illness began to decimate sunflower sea stars, the sole predators of purple sea urchins in Oregon. In turn, the purple urchins — small, spiky orbs that are native to the coast but previously dwelled in the crevices of tide pools, passively feeding on pieces of drifting kelp — had a bonanza population spurt.Purple urchins cover the sea floor at Cape Arago State Park on May 24, 2024. The urchins, whose population growth was exacerbated by a marine heat wave, have eaten most of Oregon’s kelp forests. Gosia Wozniacka / The OregonianWarmer water didn’t cause the stars’ disease, but scientists say the starfish died faster because of it. They have concluded that the Blob, an extreme heat wave in the Pacific Ocean that in 2014 raised temperatures between 4 and 10 degrees above average and lasted for more than 700 days, exacerbated both the star die-off and the urchin explosion. Without sunflower sea stars – considered the largest and fastest of the starfish species, able to grow up to 24 arms and easily outrun prey – hordes of purples took over underwater forests. They overgrazed the kelp, forming “urchin barrens,” lifeless zones covered with hungry purple urchins and not much else.The problem was not unique to the Pacific Ocean; purple urchins overran kelp forests across the globe, from Tasmania to Norway. On the West Coast, a collapse was first identified in northern California in 2019 when a study chronicled the abrupt decline of kelp there by more than 90% in 2014. Similar warning signs emerged in southern Oregon: the wads of snake-like tangles that had once washed up on beaches were becoming scarce and the dense floating mats of kelp along the shores had nearly vanished – and with them, the fish and animals that had once lived and hunted there.Despite the red flags, action to probe the extent of kelp’s loss and to stave it off has been slow. Oregon’s craggy, exposed shoreline and murky waters meant few divers had been taking stock of underwater conditions. And because the state doesn’t allow commercial harvesting of kelp, wildlife officials had neither the mandate nor the funding to regularly survey or monitor the situation.In the void, a nonprofit launched in 2019 in the small coastal town of Port Orford, about 60 miles north of the California border, bringing together local fishermen, researchers, tribal members, university students, recreational and commercial divers. The Oregon Kelp Alliance had a singular focus: to sound the alarm and take immediate action to protect Oregon’s underwater jungles.Tom Calvanese, the founder and director of the Oregon Kelp Alliance, helps lower a boat into the ocean at the Port Orford port in southern Oregon. Calvanese has been at the forefront of kelp restoration efforts in Oregon. Gosia Wozniacka / The OregonianPreviously, “the ocean felt alive, smelled alive and looked alive. The kelp was doing its job as a foundation species, supporting this vibrant ecosystem. The water was clearer. There were a lot of fish, marine mammals, birds and whales, right there, all around you,” said the group’s founder, Tom Calvanese, a fisheries scientist and former commercial urchin diver.“Fast forward to now,” he added, “the ocean without kelp doesn’t feel vibrant anymore, it doesn’t have much activity, much life.”Over the past five years, the Kelp Alliance has gained momentum, expanding up and down the coast. It’s secured more than $4 million in federal, state and private funding to conduct, in partnership with the state, a coast-wide survey of kelp and launch several scientific research and restoration projects aimed at saving kelp habitat, controlling purple urchins and bringing back sunflower sea stars. Later this summer, the group will publish a kelp status report and a comprehensive restoration plan that aims to rehabilitate Oregon’s underwater forests, although similar efforts in California so far have yielded only modest success.The soon-to-be-released report, shared early with The Oregonian/OregonLive, quantifies for the first time the amount of damage the state’s kelp forests sustained between 2010 and 2022.In all, more than two-thirds of Oregon’s kelp canopy disappeared from the southern shores. That’s nearly 900 acres, or the equivalent of 680 football fields.Floating kelp canopy observed in ODFW aerial surveys in 2010 and 2022 at three major kelp-bearing regions on the Oregon coast. Orford Reef (top, off Cape Blanco) historically held the largest kelp bed in the state by far, and has seen the most dramatic kelp decline. Meanwhile, Redfish Rocks (middle, near Port Orford) and Rogue Reef (bottom, off Gold Beach) both saw localized kelp losses that were largely balanced by a shifting kelp distribution.Oregon Department of Fish and WildlifeThe repercussions of those massive losses are just starting to emerge. The state’s commercial red sea urchin harvest is down by half from a decade ago. The recreational red abalone fishery permanently closed in December. And recreational nearshore fishing has dwindled on the southern coast.Researchers with the Kelp Alliance have estimated, based on a global assessment of kelp ecosystem values, that the 900 acres of lost kelp canopy is costing Oregon $23 million to $53 million every year. This includes the value of shrinking local fisheries as well as the ocean’s lessened ability to absorb carbon dioxide from the atmosphere. Underwater kelp forests are key to combating climate change – they can sequester up to 20 times more carbon per acre than land forests.How rising temperatures will impact kelp moving forward is unclear, although it typically does better in cooler waters that provide more nutrients. The state’s coastal surface waters warmed an average of half a degree per decade from the mid-20th century to the 2000s, according to the most recent state-funded analysis published in 2010. But the alliance’s report concludes that, unlike in other parts of the world, long-term ocean warming is likely not a cause of kelp’s decline in Oregon even as short-term heat waves played a significant role.While kelp is susceptible to heat – it experiences decreased growth and reproductive success when temperatures regularly reach 61 degrees and can die or fail to reproduce when the water warms past about 64 degrees – those thresholds have been rarely reached along Oregon’s southern shores. In fact, researchers noted that surface water temperatures at two locations, off Port Orford and at Charleston, near Coos Bay, have declined very slightly over the past 30 years.Complicating matters, a few areas, including Cape Arago State Park near Coos Bay, saw gains in kelp cover for reasons researchers don’t yet understand.Hamilton, the marine ecologist, has monitored kelp at Cape Arago for the past three years with a drone and by diving or snorkeling there about a dozen times. Every year, the underwater forest has regrown, making it one of Oregon’s bright spot outliers, with a 25% increase in canopy cover.She’s cautiously optimistic that, despite an abundance of purple urchins already on scene, it will come back this summer.Snorkeling through cloudy water at the cove this spring, the research team spotted signs of hope, anchored to the seabed.Hamilton broke the surface and yelled: “Baby kelp!”But she remains worried about the future.“There’s a theory known as tipping points. If you push a system closer and closer to a point where all of a sudden the urchins take over, they can quickly switch the kelp forest to an urchin barren,” Hamilton said after the snorkeling excursion. “We have these sites that still seem relatively healthy. We don’t know if they’re close to tipping. We don’t know if they can sustain those populations of urchins long-term. It fuels our sense of urgency and anxiety.”FEELING KELP’S LOSSThe disappearance of kelp – amid the rise and dominance of purple urchins – is being felt all along Oregon’s southern shores.This spring in Port Orford, Calvanese, the Kelp Alliance founder, and his friend Dave Lacey, a boat captain, steered a small boat out of the tiny port toward a rocky headland known as The Heads. They circled just below at Nellies Cove, a sheltered bay.Tom Calvanese, the Kelp Alliance director, and his friend Dave Lacey, a boat captain, steer a boat on May 25, 2024, out of Port Orford in southern Oregon toward Nellies Cove. The picturesque cove has become a wasteland of purple urchins. Gosia Wozniacka / The OregonianThe cove is ground zero for Oregon’s kelp restoration efforts. It’s where Calvanese, Lacey and others first began to notice signs of dramatic change.The two men, both transplants from the East Coast, recalled paddling or kayaking together just past the breakwater with their fishing poles to where a dense mat of kelp encircled the shores. Lacey, the head of a local tour company, would bring groups of recreational fishing enthusiasts. They would park their kayaks right on the edge of the kelp forest and fish over it.“We never got skunked here. We always caught fish, always,” Calvanese said.Then, about six years ago, the kelp canopy disappeared – and with it, the fish at Nellies Cove.“It got so bad, we stopped doing kayak fishing tours,” Lacey said. “We used to pull in about $10,000 every summer. Now that’s totally gone. We just gave up on it. I didn’t want to take people’s money and not catch any fish.”Calvanese, who manages Oregon State University’s field station at Port Orford, also began fielding calls from commercial urchin divers alarmed by kelp declines on nearby reefs. They took him by surprise. He had worked for an urchin diving crew while finishing his graduate degree and had seen first-hand the thick forests stretching for hundreds of acres under the waves.He realized the stakes were high. Port Orford, population 1,149, is dependent on fishing. With kelp forests dwindling, both the commercial nearshore fishery – rockfish, cabezon and greenling – and the red urchin fishery could be threatened, not to mention recreational fishing and tourism.Calvanese wanted to see the underwater changes for himself, so he dove in Nellies Cove. What he found shocked him and brought tears to his eyes, he said. The entire sea bottom was covered in purple urchins actively foraging for food. Where a thriving kelp forest had once grown, bountiful with juvenile and adult fish, he now couldn’t spot a single kelp.The fish, too, were mostly gone.A few hundred yards from that spot in Nellies Cove, commercial urchin diver Tom Butterbaugh anchored his boat, the F/V Good News, surveying the area this spring for red urchins to harvest.Urchin diving in Oregon is a dangerous job, and Butterbaugh has been searching for them under water for 24 years. Unlike the small and skinny purple urchins that have no commercial value, red urchins are harvested throughout the world for their roe — also called uni — which is considered a delicacy, especially in Japan.The business was once lucrative. Now, it’s less so. Most of the red urchins in Oregon are either gone or their roe isn’t well developed because they have to compete for food with the masses of purple urchins.Butterbaugh remembers good kelp years and bad kelp years, but it’s never been as bad as it is now, he said.He estimates he has lost over 90% of red urchin picking territory in recent years, most of it at nearby Orford Reef – the hardest-hit area for kelp decline – where he had typically harvested for six months annually.“The feeling of loss, the frustration, the helplessness when we can’t get the urchins is constantly there,” he said. “‘Where are we going to go? We already went there.’ Our [harvest] counts are getting lower and lower. Maybe this will be the year that the kelp comes back. We thought it was going to come back last year. And look at Depoe Bay, the kelp is amazing, but the urchins are skinny anyway.”The only reason he’s still in business is because the domestic market for red urchins has grown. A decade ago, he picked urchins for 50 to 80 cents per pound. Now, depending on the season and whether there’s competition from divers in Mexico or Chile, the price is up at $2 to $4.“It’s been thin ice for urchin divers,” Butterbaugh said. “The only thing keeping us afloat are the higher prices. If we lost market value, we’d go out of business.”From left, black rockfish, red urchins, sunflower sea star and red abalone. Photos courtesy Oregon Department of Fish and Wildlife Marine Reserves ProgramConcern is also growing over the future of the commercial groundfish industry in Port Orford. Kelp forests act as nurseries for juvenile rockfish and other groundfish – providing shelter, food and a place to grow – so the drastic decline of kelp beds is bound to have an impact, said Port of Port Orford Commission president Aaron Ashdown. Although local fishermen have yet to see changes in fish availability, he said, that’s likely because rockfish are some of the longest-living fish.“We might not see the negative effects of this kelp die-off until a decade or two goes by because of how long it takes for these fish to grow up,” Ashdown said. “But by then, we could see the collapse of certain species.”For the Coquille Indian Tribe, too, the decline of underwater forests has been wrenching, spelling the disappearance of tribal foods and practices, said Shelley Estes, an enrolled member of the tribe, which has inhabited Oregon’s southwestern coast for thousands of years.“Our elders said the kelp was our ‘canoe superhighway,’” said Estes, who is on the tribe’s resiliency climate task force. “Our people ran canoes up and down the coastline. That’s where we felt safe. Kelp protected us. It absorbed the shocks of the waves coming onto the shore.”One of the early victims of the disappearing kelp is red abalone, a large ocean snail that grazes on kelp and is a traditional source of nourishment and spiritual protection for the tribe. Abalone shells are also used in smudging – cleansing rituals that use burning herbs to clear out negative energies – and to make tribal regalia.Without kelp, the abalone, whose populations were already in decline prior to kelp’s collapse, have starved. The tribe can no longer harvest them and must purchase their shells on Amazon.“As a tribal member, I’m alarmed,” Estes said.PATH TO RESTORATIONRestoring kelp along Oregon’s southern shoreline may require an assortment of strategies, including, crucially, removing most of the purple urchin – somehow.A healthy bull kelp forest swayed underwater in August 2021 at Redfish Rocks, one of Oregon’s five marine reserves just south of Port Orford. The tree-like algae float up to the surface buoyed by air-filled bladders, their fronds or blades forming a thick canopy. Brandon Cole / Special to The OregonianThe Kelp Alliance initially focused on hand removing and composting purple urchins or smashing them with hammers on the seabed – under a permit from the state – at sites including Nellies Cove, Macklyn Cove in Brookings and Haystack Rock in Pacific City. But those efforts, as in California, have had limited impact thus far, due in part to limited funding that paid for only short-term removal actions.One challenge is that purple urchins can persist in a hungry zombie state for well over a year, easily outlasting the annual cycle of bull kelp and lying in wait to devour baby algae before it has a chance to regrow. As a result, scientists say, it’s extremely difficult to flip barrens back into kelp ecosystems – it requires continually removing most if not all urchins in an area. Short of that, studies and surveys have shown that urchin removal can be effective when it happens at larger, semi-discrete sites or focuses on barrens surrounded by healthy kelp.Restoring kelp forests coast-wide by removing urchins by hand is clearly not feasible.Case in point: At Orford Reef – where Butterbaugh traditionally dove for red urchins – state biologists in 2019 documented 350 million purple urchins sitting on the seabed, a 10,000% increase over a five year period. The reef, once the state’s largest underwater kelp forest, spanning about 1,655 acres or just under half the size of the city of Astoria, saw a 95% decline in kelp, the largest in Oregon, according to the new data.“We realized we could not smash our way out of this crisis,” said Calvanese, the Kelp Alliance’s founder.The group is now launching a new $2.5 million restoration initiative that ties targeted urchin removal with kelp revegetation. Divers in Oregon will remove urchins at six sites along the coast and then “seed” kelp via spore bags and other cultivation methods. The sites include not only urchin barrens such as Nellies Cove but also areas that have abundant kelp canopy yet are overrun with urchins, such as Cape Arago.Separately, the group is mounting a kelp mariculture project in the waters around Port Orford. It will grow bull kelp on vertical mooring lines off the ocean bottom and out of reach of hungry urchins. The kelp will be used to make animal feed or fertilizer – a boost to the local economy – and spores will be saved for the kelp revegetation at restoration sites. The group is also working with local seaweed farms to collect purple urchins to fatten them up in land-based tanks with the hope to make them commercially viable.Ultimately, said Calvanese, restoration can stave off the complete disappearance of kelp along the West Coast by protecting a network of small sites that can maintain kelp’s genetic diversity and eventually repopulate urchin barrens.“If we can restore and maintain these oases where we continue to produce kelp spores then we have a chance to regrow from there,” he said. “We can also protect the remaining kelp we still have and not just watch it shrivel up.”MORE: Does kelp restoration work?But to make kelp’s comeback viable at scale, Calvanese and others are betting big on returning the sunflower sea stars – purple urchins’ only predator in the state – to the ocean.Scott Groth, a marine scientist with the Oregon Department of Fish and Wildlife, holds a sunflower sea star off the Oregon coast near Port Orford. The photo was taken before a mysterious wasting disease wiped out the population of the sea stars in Oregon beginning in 2013. Scott Groth / Oregon Department of Fish and WildlifeMarine ecologists Aaron Galloway and Sarah Gravem, with the University of Oregon and Oregon State University, have been able to show that the sunflower sea stars could potentially regulate purple sea urchin populations and, as a result, restore and maintain healthy kelp forests.Their study published last year indicates that sunflower sea stars don’t discriminate between fully grown healthy urchins and starved, nutritionally poor urchins similar to those that dwell in urchin barrens. In fact, during experiments the sea stars ate more skinny, hungry urchins than healthy ones, likely because it takes a shorter amount of time to digest them, Galloway said.Modeling also showed that, at the densities of sea stars before the wasting disease, there were enough stars to stop urchins from turning kelp forests into barrens.With those results in mind, the scientists, who are both members of the Kelp Alliance, are working toward a captive breeding program in Oregon, with the end-goal being reintroduction to the wild. That reality is now a step closer as Oregon has seen an increase in the sightings of sunflower sea stars, meaning researchers can start collecting them for local experiments and breeding. Earlier this year, Galloway secured approval for a permit to collect 20 in Oregon waters to launch the endeavors. He’s working closely with a lab in Washington that was the first to successfully breed the animals.Eventually, Galloway said, he hopes to breed and release thousands of sunflower sea stars into Oregon waters and see how they behave in urchin barrens. It’s unclear whether this will work, he admits. Though several research centers and aquariums around the U.S. are now racing to breed the stars, which the federal government last year proposed to list as threatened under the Endangered Species Act, no one has attempted such a release thus far.“It’s a dream for us,” he said. “If we put a bunch of them at a reef or declining kelp forest, will it cause a recovery? Will the stars eat the urchins or will they just leave and go somewhere else?”In September 2023, a drone captured a thick bull kelp canopy growing just off of Cape Foulweather’s Otter Crest State Scenic Viewpoint. The cape, just south of Depoe Bay, was one of the few areas on Oregon’s coast that saw an increase in kelp last year. Sara Hamilton / Oregon Kelp Alliance.Because that’s a long-term endeavor, Gravem said, the state needs to urgently step up to regularly monitor, manage and restore kelp forests, similar to how it manages land-based forests, grasslands and estuaries.“For a long time, we’ve been hesitant to intervene in the ocean. It’s so big and we thought that it would rebound if we just left it alone,” Gravem said. “But it’s becoming increasingly clear that it’s not rebounding on its own. If anything, it’s getting worse because of climate change. So we need to … start helping it along.”— Gosia Wozniacka covers environmental justice, climate change, the clean energy transition and other environmental issues. Reach her at gwozniacka@oregonian.com or 971-421-3154.
As marine heat waves wreak havoc on Oregon’s ocean ecosystems, the collapse of kelp forests could prove catastrophic to marine life, fisheries and tribes.
On a chilly May morning at a sandy beach 15 miles southwest of Coos Bay, marine ecologist Sara Hamilton poured hot water from a thermos into her thick wetsuit, neoprene dive boots and gloves. Snorkeling mask and fins in hand, she made her way toward the jutting headland of Cape Arago State Park, across slippery rocks draped in seaweed, mussels and barnacles and crevices teeming with green sea anemones.
Hamilton eased herself into the ocean, a frigid 49 degrees that day, followed by several colleagues who braced themselves on surf-drenched rocks. But the waves crashed too high, sending the team into shallower waters before they floated and dove down.
A lush, towering kelp forest had sprung up under the waves in this cove in each of the past three summers, providing refuge to juvenile rockfish and salmon, shrimp, whales and countless other creatures. But it was unclear if it would regrow this year or become the latest casualty of an upended marine ecosystem that could herald the future impact of global warming on Oregon’s coast.
For millennia, underwater forests of seaweed or large brown algae stretched from the seafloor to the ocean’s surface, forming canopies, much like trees, and providing food, shelter and hunting grounds to countless animals. Bull kelp, the predominant species found along the southern third of Oregon shores, is one of the world’s fastest growers – rising at a rate of up to 10 inches per day and reaching heights of up to about 100 feet, establishing itself as the sequoia of the seas. Kelp has helped protect the coastline from storms and supported local fisheries, tribal fishing and cultural practices.
But over the past decade, according to new data, Oregon lost more than two-thirds of that kelp canopy.
Kelp’s troubles on the West Coast started in 2013 when a mysterious illness began to decimate sunflower sea stars, the sole predators of purple sea urchins in Oregon. In turn, the purple urchins — small, spiky orbs that are native to the coast but previously dwelled in the crevices of tide pools, passively feeding on pieces of drifting kelp — had a bonanza population spurt.
Purple urchins cover the sea floor at Cape Arago State Park on May 24, 2024. The urchins, whose population growth was exacerbated by a marine heat wave, have eaten most of Oregon’s kelp forests. Gosia Wozniacka / The Oregonian
Warmer water didn’t cause the stars’ disease, but scientists say the starfish died faster because of it. They have concluded that the Blob, an extreme heat wave in the Pacific Ocean that in 2014 raised temperatures between 4 and 10 degrees above average and lasted for more than 700 days, exacerbated both the star die-off and the urchin explosion. Without sunflower sea stars – considered the largest and fastest of the starfish species, able to grow up to 24 arms and easily outrun prey – hordes of purples took over underwater forests. They overgrazed the kelp, forming “urchin barrens,” lifeless zones covered with hungry purple urchins and not much else.
The problem was not unique to the Pacific Ocean; purple urchins overran kelp forests across the globe, from Tasmania to Norway. On the West Coast, a collapse was first identified in northern California in 2019 when a study chronicled the abrupt decline of kelp there by more than 90% in 2014. Similar warning signs emerged in southern Oregon: the wads of snake-like tangles that had once washed up on beaches were becoming scarce and the dense floating mats of kelp along the shores had nearly vanished – and with them, the fish and animals that had once lived and hunted there.
Despite the red flags, action to probe the extent of kelp’s loss and to stave it off has been slow. Oregon’s craggy, exposed shoreline and murky waters meant few divers had been taking stock of underwater conditions. And because the state doesn’t allow commercial harvesting of kelp, wildlife officials had neither the mandate nor the funding to regularly survey or monitor the situation.
In the void, a nonprofit launched in 2019 in the small coastal town of Port Orford, about 60 miles north of the California border, bringing together local fishermen, researchers, tribal members, university students, recreational and commercial divers. The Oregon Kelp Alliance had a singular focus: to sound the alarm and take immediate action to protect Oregon’s underwater jungles.
Tom Calvanese, the founder and director of the Oregon Kelp Alliance, helps lower a boat into the ocean at the Port Orford port in southern Oregon. Calvanese has been at the forefront of kelp restoration efforts in Oregon. Gosia Wozniacka / The Oregonian
Previously, “the ocean felt alive, smelled alive and looked alive. The kelp was doing its job as a foundation species, supporting this vibrant ecosystem. The water was clearer. There were a lot of fish, marine mammals, birds and whales, right there, all around you,” said the group’s founder, Tom Calvanese, a fisheries scientist and former commercial urchin diver.
“Fast forward to now,” he added, “the ocean without kelp doesn’t feel vibrant anymore, it doesn’t have much activity, much life.”
Over the past five years, the Kelp Alliance has gained momentum, expanding up and down the coast. It’s secured more than $4 million in federal, state and private funding to conduct, in partnership with the state, a coast-wide survey of kelp and launch several scientific research and restoration projects aimed at saving kelp habitat, controlling purple urchins and bringing back sunflower sea stars. Later this summer, the group will publish a kelp status report and a comprehensive restoration plan that aims to rehabilitate Oregon’s underwater forests, although similar efforts in California so far have yielded only modest success.
The soon-to-be-released report, shared early with The Oregonian/OregonLive, quantifies for the first time the amount of damage the state’s kelp forests sustained between 2010 and 2022.
In all, more than two-thirds of Oregon’s kelp canopy disappeared from the southern shores. That’s nearly 900 acres, or the equivalent of 680 football fields.
![Kelp canopy map](https://cdn.prod.website-files.com/606103d4066949639878560d/669f92ca8d50a57d21b6192a_CEZRHHJX5BCV3BTTUQGLNV4J2E.jpeg)
Floating kelp canopy observed in ODFW aerial surveys in 2010 and 2022 at three major kelp-bearing regions on the Oregon coast. Orford Reef (top, off Cape Blanco) historically held the largest kelp bed in the state by far, and has seen the most dramatic kelp decline. Meanwhile, Redfish Rocks (middle, near Port Orford) and Rogue Reef (bottom, off Gold Beach) both saw localized kelp losses that were largely balanced by a shifting kelp distribution.Oregon Department of Fish and Wildlife
The repercussions of those massive losses are just starting to emerge. The state’s commercial red sea urchin harvest is down by half from a decade ago. The recreational red abalone fishery permanently closed in December. And recreational nearshore fishing has dwindled on the southern coast.
Researchers with the Kelp Alliance have estimated, based on a global assessment of kelp ecosystem values, that the 900 acres of lost kelp canopy is costing Oregon $23 million to $53 million every year. This includes the value of shrinking local fisheries as well as the ocean’s lessened ability to absorb carbon dioxide from the atmosphere. Underwater kelp forests are key to combating climate change – they can sequester up to 20 times more carbon per acre than land forests.
How rising temperatures will impact kelp moving forward is unclear, although it typically does better in cooler waters that provide more nutrients. The state’s coastal surface waters warmed an average of half a degree per decade from the mid-20th century to the 2000s, according to the most recent state-funded analysis published in 2010. But the alliance’s report concludes that, unlike in other parts of the world, long-term ocean warming is likely not a cause of kelp’s decline in Oregon even as short-term heat waves played a significant role.
While kelp is susceptible to heat – it experiences decreased growth and reproductive success when temperatures regularly reach 61 degrees and can die or fail to reproduce when the water warms past about 64 degrees – those thresholds have been rarely reached along Oregon’s southern shores. In fact, researchers noted that surface water temperatures at two locations, off Port Orford and at Charleston, near Coos Bay, have declined very slightly over the past 30 years.
Complicating matters, a few areas, including Cape Arago State Park near Coos Bay, saw gains in kelp cover for reasons researchers don’t yet understand.
Hamilton, the marine ecologist, has monitored kelp at Cape Arago for the past three years with a drone and by diving or snorkeling there about a dozen times. Every year, the underwater forest has regrown, making it one of Oregon’s bright spot outliers, with a 25% increase in canopy cover.
She’s cautiously optimistic that, despite an abundance of purple urchins already on scene, it will come back this summer.
Snorkeling through cloudy water at the cove this spring, the research team spotted signs of hope, anchored to the seabed.
Hamilton broke the surface and yelled: “Baby kelp!”
But she remains worried about the future.
“There’s a theory known as tipping points. If you push a system closer and closer to a point where all of a sudden the urchins take over, they can quickly switch the kelp forest to an urchin barren,” Hamilton said after the snorkeling excursion. “We have these sites that still seem relatively healthy. We don’t know if they’re close to tipping. We don’t know if they can sustain those populations of urchins long-term. It fuels our sense of urgency and anxiety.”
FEELING KELP’S LOSS
The disappearance of kelp – amid the rise and dominance of purple urchins – is being felt all along Oregon’s southern shores.
This spring in Port Orford, Calvanese, the Kelp Alliance founder, and his friend Dave Lacey, a boat captain, steered a small boat out of the tiny port toward a rocky headland known as The Heads. They circled just below at Nellies Cove, a sheltered bay.
Tom Calvanese, the Kelp Alliance director, and his friend Dave Lacey, a boat captain, steer a boat on May 25, 2024, out of Port Orford in southern Oregon toward Nellies Cove. The picturesque cove has become a wasteland of purple urchins. Gosia Wozniacka / The Oregonian
The cove is ground zero for Oregon’s kelp restoration efforts. It’s where Calvanese, Lacey and others first began to notice signs of dramatic change.
The two men, both transplants from the East Coast, recalled paddling or kayaking together just past the breakwater with their fishing poles to where a dense mat of kelp encircled the shores. Lacey, the head of a local tour company, would bring groups of recreational fishing enthusiasts. They would park their kayaks right on the edge of the kelp forest and fish over it.
“We never got skunked here. We always caught fish, always,” Calvanese said.
Then, about six years ago, the kelp canopy disappeared – and with it, the fish at Nellies Cove.
“It got so bad, we stopped doing kayak fishing tours,” Lacey said. “We used to pull in about $10,000 every summer. Now that’s totally gone. We just gave up on it. I didn’t want to take people’s money and not catch any fish.”
Calvanese, who manages Oregon State University’s field station at Port Orford, also began fielding calls from commercial urchin divers alarmed by kelp declines on nearby reefs. They took him by surprise. He had worked for an urchin diving crew while finishing his graduate degree and had seen first-hand the thick forests stretching for hundreds of acres under the waves.
He realized the stakes were high. Port Orford, population 1,149, is dependent on fishing. With kelp forests dwindling, both the commercial nearshore fishery – rockfish, cabezon and greenling – and the red urchin fishery could be threatened, not to mention recreational fishing and tourism.
Calvanese wanted to see the underwater changes for himself, so he dove in Nellies Cove. What he found shocked him and brought tears to his eyes, he said. The entire sea bottom was covered in purple urchins actively foraging for food. Where a thriving kelp forest had once grown, bountiful with juvenile and adult fish, he now couldn’t spot a single kelp.
The fish, too, were mostly gone.
A few hundred yards from that spot in Nellies Cove, commercial urchin diver Tom Butterbaugh anchored his boat, the F/V Good News, surveying the area this spring for red urchins to harvest.
Urchin diving in Oregon is a dangerous job, and Butterbaugh has been searching for them under water for 24 years. Unlike the small and skinny purple urchins that have no commercial value, red urchins are harvested throughout the world for their roe — also called uni — which is considered a delicacy, especially in Japan.
The business was once lucrative. Now, it’s less so. Most of the red urchins in Oregon are either gone or their roe isn’t well developed because they have to compete for food with the masses of purple urchins.
Butterbaugh remembers good kelp years and bad kelp years, but it’s never been as bad as it is now, he said.
He estimates he has lost over 90% of red urchin picking territory in recent years, most of it at nearby Orford Reef – the hardest-hit area for kelp decline – where he had typically harvested for six months annually.
“The feeling of loss, the frustration, the helplessness when we can’t get the urchins is constantly there,” he said. “‘Where are we going to go? We already went there.’ Our [harvest] counts are getting lower and lower. Maybe this will be the year that the kelp comes back. We thought it was going to come back last year. And look at Depoe Bay, the kelp is amazing, but the urchins are skinny anyway.”
The only reason he’s still in business is because the domestic market for red urchins has grown. A decade ago, he picked urchins for 50 to 80 cents per pound. Now, depending on the season and whether there’s competition from divers in Mexico or Chile, the price is up at $2 to $4.
“It’s been thin ice for urchin divers,” Butterbaugh said. “The only thing keeping us afloat are the higher prices. If we lost market value, we’d go out of business.”
From left, black rockfish, red urchins, sunflower sea star and red abalone. Photos courtesy Oregon Department of Fish and Wildlife Marine Reserves Program
Concern is also growing over the future of the commercial groundfish industry in Port Orford. Kelp forests act as nurseries for juvenile rockfish and other groundfish – providing shelter, food and a place to grow – so the drastic decline of kelp beds is bound to have an impact, said Port of Port Orford Commission president Aaron Ashdown. Although local fishermen have yet to see changes in fish availability, he said, that’s likely because rockfish are some of the longest-living fish.
“We might not see the negative effects of this kelp die-off until a decade or two goes by because of how long it takes for these fish to grow up,” Ashdown said. “But by then, we could see the collapse of certain species.”
For the Coquille Indian Tribe, too, the decline of underwater forests has been wrenching, spelling the disappearance of tribal foods and practices, said Shelley Estes, an enrolled member of the tribe, which has inhabited Oregon’s southwestern coast for thousands of years.
“Our elders said the kelp was our ‘canoe superhighway,’” said Estes, who is on the tribe’s resiliency climate task force. “Our people ran canoes up and down the coastline. That’s where we felt safe. Kelp protected us. It absorbed the shocks of the waves coming onto the shore.”
One of the early victims of the disappearing kelp is red abalone, a large ocean snail that grazes on kelp and is a traditional source of nourishment and spiritual protection for the tribe. Abalone shells are also used in smudging – cleansing rituals that use burning herbs to clear out negative energies – and to make tribal regalia.
Without kelp, the abalone, whose populations were already in decline prior to kelp’s collapse, have starved. The tribe can no longer harvest them and must purchase their shells on Amazon.
“As a tribal member, I’m alarmed,” Estes said.
PATH TO RESTORATION
Restoring kelp along Oregon’s southern shoreline may require an assortment of strategies, including, crucially, removing most of the purple urchin – somehow.
A healthy bull kelp forest swayed underwater in August 2021 at Redfish Rocks, one of Oregon’s five marine reserves just south of Port Orford. The tree-like algae float up to the surface buoyed by air-filled bladders, their fronds or blades forming a thick canopy. Brandon Cole / Special to The Oregonian
The Kelp Alliance initially focused on hand removing and composting purple urchins or smashing them with hammers on the seabed – under a permit from the state – at sites including Nellies Cove, Macklyn Cove in Brookings and Haystack Rock in Pacific City. But those efforts, as in California, have had limited impact thus far, due in part to limited funding that paid for only short-term removal actions.
One challenge is that purple urchins can persist in a hungry zombie state for well over a year, easily outlasting the annual cycle of bull kelp and lying in wait to devour baby algae before it has a chance to regrow. As a result, scientists say, it’s extremely difficult to flip barrens back into kelp ecosystems – it requires continually removing most if not all urchins in an area. Short of that, studies and surveys have shown that urchin removal can be effective when it happens at larger, semi-discrete sites or focuses on barrens surrounded by healthy kelp.
Restoring kelp forests coast-wide by removing urchins by hand is clearly not feasible.
Case in point: At Orford Reef – where Butterbaugh traditionally dove for red urchins – state biologists in 2019 documented 350 million purple urchins sitting on the seabed, a 10,000% increase over a five year period. The reef, once the state’s largest underwater kelp forest, spanning about 1,655 acres or just under half the size of the city of Astoria, saw a 95% decline in kelp, the largest in Oregon, according to the new data.
“We realized we could not smash our way out of this crisis,” said Calvanese, the Kelp Alliance’s founder.
The group is now launching a new $2.5 million restoration initiative that ties targeted urchin removal with kelp revegetation. Divers in Oregon will remove urchins at six sites along the coast and then “seed” kelp via spore bags and other cultivation methods. The sites include not only urchin barrens such as Nellies Cove but also areas that have abundant kelp canopy yet are overrun with urchins, such as Cape Arago.
Separately, the group is mounting a kelp mariculture project in the waters around Port Orford. It will grow bull kelp on vertical mooring lines off the ocean bottom and out of reach of hungry urchins. The kelp will be used to make animal feed or fertilizer – a boost to the local economy – and spores will be saved for the kelp revegetation at restoration sites. The group is also working with local seaweed farms to collect purple urchins to fatten them up in land-based tanks with the hope to make them commercially viable.
Ultimately, said Calvanese, restoration can stave off the complete disappearance of kelp along the West Coast by protecting a network of small sites that can maintain kelp’s genetic diversity and eventually repopulate urchin barrens.
“If we can restore and maintain these oases where we continue to produce kelp spores then we have a chance to regrow from there,” he said. “We can also protect the remaining kelp we still have and not just watch it shrivel up.”
MORE: Does kelp restoration work?
But to make kelp’s comeback viable at scale, Calvanese and others are betting big on returning the sunflower sea stars – purple urchins’ only predator in the state – to the ocean.
Scott Groth, a marine scientist with the Oregon Department of Fish and Wildlife, holds a sunflower sea star off the Oregon coast near Port Orford. The photo was taken before a mysterious wasting disease wiped out the population of the sea stars in Oregon beginning in 2013. Scott Groth / Oregon Department of Fish and Wildlife
Marine ecologists Aaron Galloway and Sarah Gravem, with the University of Oregon and Oregon State University, have been able to show that the sunflower sea stars could potentially regulate purple sea urchin populations and, as a result, restore and maintain healthy kelp forests.
Their study published last year indicates that sunflower sea stars don’t discriminate between fully grown healthy urchins and starved, nutritionally poor urchins similar to those that dwell in urchin barrens. In fact, during experiments the sea stars ate more skinny, hungry urchins than healthy ones, likely because it takes a shorter amount of time to digest them, Galloway said.
Modeling also showed that, at the densities of sea stars before the wasting disease, there were enough stars to stop urchins from turning kelp forests into barrens.
With those results in mind, the scientists, who are both members of the Kelp Alliance, are working toward a captive breeding program in Oregon, with the end-goal being reintroduction to the wild. That reality is now a step closer as Oregon has seen an increase in the sightings of sunflower sea stars, meaning researchers can start collecting them for local experiments and breeding. Earlier this year, Galloway secured approval for a permit to collect 20 in Oregon waters to launch the endeavors. He’s working closely with a lab in Washington that was the first to successfully breed the animals.
Eventually, Galloway said, he hopes to breed and release thousands of sunflower sea stars into Oregon waters and see how they behave in urchin barrens. It’s unclear whether this will work, he admits. Though several research centers and aquariums around the U.S. are now racing to breed the stars, which the federal government last year proposed to list as threatened under the Endangered Species Act, no one has attempted such a release thus far.
“It’s a dream for us,” he said. “If we put a bunch of them at a reef or declining kelp forest, will it cause a recovery? Will the stars eat the urchins or will they just leave and go somewhere else?”
In September 2023, a drone captured a thick bull kelp canopy growing just off of Cape Foulweather’s Otter Crest State Scenic Viewpoint. The cape, just south of Depoe Bay, was one of the few areas on Oregon’s coast that saw an increase in kelp last year. Sara Hamilton / Oregon Kelp Alliance.
Because that’s a long-term endeavor, Gravem said, the state needs to urgently step up to regularly monitor, manage and restore kelp forests, similar to how it manages land-based forests, grasslands and estuaries.
“For a long time, we’ve been hesitant to intervene in the ocean. It’s so big and we thought that it would rebound if we just left it alone,” Gravem said. “But it’s becoming increasingly clear that it’s not rebounding on its own. If anything, it’s getting worse because of climate change. So we need to … start helping it along.”
— Gosia Wozniacka covers environmental justice, climate change, the clean energy transition and other environmental issues. Reach her at gwozniacka@oregonian.com or 971-421-3154.