Transcript

1.8.26 · Smithsonian Magazine

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Speaker 1: Welcome. This is Rebecca Shore for Radio Eye and to
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day I will be reading the Smithsonian Magazine dated December
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twenty twenty five. As a reminder, Radio Eye is a
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reading service intended for people who are blind or have
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other disabilities that make it difficult to read printed material.
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Please join me now for the article under Water forests
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return to life off the coast of California, and that
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might be good news for the entire planet, by Evan I. Schwartz.
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Every year, on a late summer night, Eva Pagling joins
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a group of fellow Chumash paddlers who climb into a tomol,
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a hand crafted wood plank canoe, for an eight to
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ten hour voyage. From the California mainland. They head for
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the largest of the Channel Islands, an archipelago sometimes called
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the Galapgos of North America due to its stunning biodiversity.
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The island appears on maps as Santa Cruz. The Chumash
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call it Lemieux. Pagaling, who is now thirty five, has
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been taking part in the annual journey since she was ten.
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As the youngest daughter of a master canoe builder, she
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grew up hearing oral histories and learning songs about her
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indigenous group, among the first people to inhabit the California
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coast at least thirteen thousand years ago. But she emphasized
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that this annual tradition is more than ceremonial. This isn't
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a replica of a tomol, she said. We aren't just
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descendants of the Chumash. This isn't just a re enactment
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of our journey. This is who we are and what
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we are doing right now. But one thing that has
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changed over the generations is the condition of the channel waters.
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For millennia, the Chumash and other indigenous people sustained themselves
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in part by spear hunting in kelp forests teeming with fish.
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We still catch halibut, tuna, and rockfish, said Pagaling, who
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is a Chumash tribal marine consultant as well as a
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trained rescued but these marine ecosystems are not as healthy
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as when our ancestors were eating the fish. Poggling is
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the board president of the nonprofit Ocean Origins, and she
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collaborates with marine scientists to restore one of the planet's
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most precious resources, the kelp forests that once grew thick
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and wide in tidal corridors up and down the Pacific coast.
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Kelp forests keep ocean waters clean and oxygenated while hosting
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a wide variety of fish and sea life. These green
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and amber stalks of aquatic vegetation, which grow up to
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one hundred seventy five feet from the seafloor to the surface,
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not only combat pollution but also mitigate climate change. Kelp
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forests absorb carbon dioxide from both the air and water
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that would otherwise linger for centuries. They can absorb twenty
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times more CO two compared with the same size terrestrial forests.
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In the eighteen thirties, Charles Darwin was amazed by the
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kelp ecosystems he found flourishing in the Pacific waters around
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the Galapagos. I could only compare these great aquatic forests
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with the terrestrial ones in the intertropical regions, he wrote
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in his journal. Yet, if in any country a forest
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was destroyed, I do not believe nearly so many species
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of animals would perish as would here from the destruction
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of the kelp. Kelp is an umbrella term for thirty
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types of algae that grow along nearly a third of
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the world's coast lines in Maine and Long Island in
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the United Kingdom, in Norway, in Tasmania and Southern Africa,
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in Argentina and Japan, with a global coverage of more
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than two million square miles, kelp takes up roughly the
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same space as the Amazon rainforest, but few places in
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recorded history have had more abundant kelp forests than the
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eight hundred and forty miles along the California coast line
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over the past few hundred years. That changed. First came
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the eighteenth century fur traders, who trapped the sea otters
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of Monterey Bay, natural predators of the purple urchins that
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feast on kelp stalks, stems, and blades. By the early
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twentieth century, otter populations were hunted to near extinction. Kelp
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beds were consumed until they turned into desolate underwater areas
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known as urchin barrens. Fish populations disappeared with the kelp.
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Then came the rise of the automobile. In nineteen twenty one,
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California created the world's first tide lands oil and gas
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leasing program, attracting energy producers that drilled hundreds of offshore
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oil wells across the Santa Barbara Channel, oil platforms rose
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up from the sea. Oil leaks became common along with
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the bubbling up of ocean floor tars. On January twenty eighth,
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nineteen sixty nine, one of the Union Oil Company's main
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offshore platforms had a blow out, the largest in u
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S history at the time. As many as four point
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two million gallons of crude oil poured into the sea,
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killing thousands of sea birds, seals, and sea lions, and
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also destroying the kelp forests. The drilling didn't stop, but
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mass protests and the burgeoning environmental movement pushed the federal
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government to set aside certain tidal waters as nature reserves.
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In nineteen eighty, the Channel Islands National Greene Sanctuary began
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protecting endangered species and sensitive habitats in nearly fifteen hundred
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square miles of ocean waters around the five Northern Channel Islands.
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Yet the Channel waters by Santa Barbar's main land remained
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open to drilling and industrial uses. In recent years, the
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most destructive culprit has been climate change. From twenty thirteen
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to twenty sixteen, the entire Pacific coast was hit with
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unprecedented Al Nino events, when differentials in global winds and
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air temperatures set off superstorms. In twenty fifteen alone, sixteen
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tropical cyclones roiled the Central Pacific hurricane base, with rising
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water temperatures whacking kelp ecosystems out of balance. Nick Bond,
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climatologist for the state of Washington, called this marine heat
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wave the Blob after the nineteen fifty eight b movie.
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Some celp beds lingered in remnants, while others disappeared almost entirely,
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replaced by piles of purple urchins. It's like seeing a
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forest that's been clearer cut, said marine conservationist Nora Eddy,
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the associate director of Ocean's Programs for the Nature Conservancy
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in California. It's that shocking. In twenty fifteen, the Northern
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Chumash Tribal Council submitted a nomination to the federal government
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for its own marine protected area. In November twenty twenty four,
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it became official. The Chumash Heritage National Marine Sanctuary now
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begins at the tip of the Channel Islands and stretches
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north over one hundred and sixteen miles of shore, more
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than thirteen percent of California's coast, more than forty five
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hundred square miles of tidal waters are now protected from
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offshore oil drilling, pollution, industrial development, overfishing, and habitat destruction.
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I wanted to see a healthy kelp forest for myself.
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On board was Selina Smith, a marine biologist who co
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founded Ocean Origins along with Pagling and two others. Smith
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also served as director of education at the Reefcheck Foundation,
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a global organization that documents both coral reefs and kelp forests.
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On the choppy two hour outbound boat ride, Smith told
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me about how advanced ecological modeling, genetic studies of kelp
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and underwater mapping are being deployed for restoration projects by
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learning how and why the algae thrive under certain conditions.
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Ocean Origins aims to restore kelp in many locations. Its
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team members regularly find plastic and other trash stuck in
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the blades. My Lar balloons are horrible, Smith said, they
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are definitely harmful to the marine environment and its occupants.
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The boat dropped anchor in a spot so close to
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the ancient volcanic rock of Limieux that we could almost
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peer into the sea caves that line its shores. The
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surface of the water was teeming with kelp, so it
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looked like we had come to the right place. I
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took a ladder down to a small platform and let
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myself fall backward into the sea. The fifty five degree
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water was perfect for kelp growth, and magnificent visibility offered
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pristine views of the underwater forest. I swam toward the
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stalks until I found myself inside amber cathedrals of giant kelp,
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a robust species native to southern California. A group of
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whiskered sea lions came out to greet us, with bodies
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twice as long as otters and leathery skin rather than fur.
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The lions police these places, feasting on fish to maintain
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their weight for males that can be upwards of seven
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hundred pounds. The kelp breefs were a riot of color,
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populated with emerald, navy and ginger fish, spindly lobsters with
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bright yellow eyes, golden sea stars, anemones with magenta tentacles
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that gave a turquoise glow, and kelp shaked like olive
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feather boas, and butter scotch bulbs. More than a thousand
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documented species of plants and animals can be found here.
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Drawing many gazes from the divers were the Nouda branches
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sea slugs that appeared in vibrant blue and orange. This
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ecosystem was thriving for one main reason. It had been
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cleaned up and then left alone. Areas that are protected
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from fishing tend to have higher amounts of kelp, creating
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a better environment and generating more diversity. Smith said this
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past year has been an especially good one. Over the decades,
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there have been several notable stories of successful kelp revival
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and the waters New Monterey scientists and enthusiasts boat out
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weekly to dive into and monitor the aquatic forests. Ever
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since nineteen eighty four, the Monterey Bay Aquarium has been
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helping protect the local waters from pollution and industrial development.
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The Monterey Bay National Marine Sanctuary, established in nineteen ninety two,
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expanded the effort, and now some three thousand sea otters
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thrive between Half Moon Bay near San Francisco and Point
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Concepcion near Santa Barbara. The kelps, ebbs and flows depend
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mostly on water temperature off the coast of Pallas Verdes,
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a famed surfing spot thirty miles south of Los Angeles
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marine biologist Tom Ford, CEO of the Bay Foundation, operates
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one of the world's most impressive kelp restoration projects. After
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moving to the area in nineteen ninety eight, Ford went
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out scuba diving and encountered a kelp forest. That was it,
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he said, I was hooked. For his master's degree at
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the University of California, Los Angeles, Ford studied the trajectories
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of loss and recovery of kelp all over the world
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and the many creatures that depended on it. If it's gone,
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he says, they're essentially homeless. By twenty thirteen, Ford was
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ready to start work with a group of student volunteers,
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but he had barely gotten going when the coast was
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hit by the blob. We stopped restoration work. He said.
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What they found were ailing purple ecanoderms as far as
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the eye could see. They had consumed all the kelp,
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and now they were starving. Their spines covered entire ocean
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floors like marble. Tile Ford told me he and his
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team dove into the water and smashed urchins to death
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with hammers, which released nutrients that would nourish other marine creatures.
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It's taken a decade of relentless work to clean out
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enough urchins and replenish the area. We restarted this ecological
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machine so it could restore its own health. Ford said.
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By twenty twenty four, a seventy acre forest the size
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of about fifty three football fields, became the biggest kelp
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restoration success story in the United States. A year later,
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when I rowed on the dive boat with Ford and
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his crew, the restoration area had grown to eighty acres,
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or around sixty football fields. We swam in the aftermath
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of the summer heat wave, with the water's surface at
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a toasty seventy two degrees. The heat was causing some
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of the kelp blades to disintegrate, clouding the waters. But
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Ford showed me how the same ocean bottom that once
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looked pale and dead was now covered in kelp stalks
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and green, red, and brown algae. Healthy urchins were present
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in small numbers. Ford's studies show that having fewer than
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three urchins per ten square feet keeps the ecosystem in balance.
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Yet he acknowledged that clearing out urchins by hand takes
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too long. He told me his look looking forward to
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new tools and techniques that could make restoration easier and
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more productive. When it comes to the economy in the planet,
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cultivating kelp is a worthwhile venture. Perhaps the most promising
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business model is an outfit called Ocean Rainforest, which had
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success growing sugar kelp in the Faroe Islands of the
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North Atlantic Ocean and shows the Santa Barbara Channel as
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its next locale. Its eighty six acre giant kelp farm,
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created from scratch, four miles off shore, grows kelps on
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ropes that are attached to buoys. The boys have GPS
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devices on them and the team does bi weekly monitoring,
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taking measurements of water temperature, nutrients, and salinity. The entire
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farm is engineered as one unit. Douglas Bush, the director
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of California operations for Ocean Rainforest, said on a visit
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to his land based facility in Galda, California, Bush showed
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me giant metal vats that process the kelp into liquid
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bios timulant for agriculture. By spraying this natural compound on soil,
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farmers hope to reduce the need for artificial fertilizers that
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give off nitrous oxide, a potent greenhouse gas that traps
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three hundred times as much heat per pound. As CO two,
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the kelp based product may boost yields and reduce the
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water needed for cash crops ranging from almonds and avocados
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to strawberries and grapes. Those are benefits attributed to seaweed
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biostimulants in general. Bush noted carefully, our hope is to
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evaluate those claims in trials using our product. Because California
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farms produce nearly half of America's vegetables and three quarters
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of its fruit and nuts, improving local agricultural techniques is
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no small achievement. The reason we are here is to
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be part of the solution to improve regional food systems,
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to be a creative tool in the toolkit for regenerative agriculture.
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Bush said, by cultivating kelp, he hoped to help meet
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the growing demand for seaweed products without putting strain on
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existing wild kelp forests. Brian von Hertzen, a planetary scientist
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who is the founder and executive director of the Climate Foundation,
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a nonprofit founded in California, believes that using kelp as
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a biostimulant for agriculture is a gigantic financial opportunity. Furthermore,
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the seaweed forests play key roles in natural climate repair,
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which is essential at this late stage in our climate journey,
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he said. Von Hertzon and his team invented growing lattices
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with electric motors that lower seaweeds each night to absorb
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nutrients and raise them up to the surface each morning
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to catch full sunlight and absorb carbon dioxide in the
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top few feet of the sea. This enables growth in
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areas that don't have enough natural upwelling due to warming waters.
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The foundation has a Kelp farm in Philippines Waters where
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it sells a KELP based fertilizer called Big Grow. In
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twenty twenty three, Von Herdson's group began hosting marine permaculture
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workshops in California to raise awareness. The group now collaborates
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with Ocean Origins as well as with scientists at the
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University of California, Santa Barbara. Removing CO two from the
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air is expensive, with methods like direct air capture machines
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driven by giant fans, each ton of carbon can cost
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as much as one thousand dollars to capture. Von Hertzon
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estimates that KELP can remove CO two at a cost
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of just twenty dollars to eighty five dollars per ton
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without requiring any machinery. A single acre of kelp forest
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can take in sixteen tons, von Herdson said, but our
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arrays can do more than double that, thirty five tons
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of CO two per acre per year, or about the
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annual emissions of six gasoline cars. Existing global seaweed forests
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can capture nearly two hundred million tons of CO two
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a year while also giving a five hundred billion dollar
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boost in ecosystem services to industries, including fishing. Expanding them
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is an excellent investment, said von Herdson, both financially and environmentally,
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and using biostimulants can boost the climate benefit even more,
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both by reducing nitrous oxide emissions and by cutting the
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CO two emissions that come both from making artificial fertilizers
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and from shipping them to farmers. California is already outpacing
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the rest of the country, and reducing fossil fuel emissions
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KELP would help the state meet its target of reaching
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net zero emissions by twenty forty five, at least five
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years sooner than the Paris Agreements goal of twenty fifty.
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Seaweeds currently grow across nearly one percent of the world's
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temperate coastal ocean waters. Getting back to pre industrial levels
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of about two percent would be revolutionary. Von hertzon is
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folks On specific species, which grow three times faster than
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other kelp. He said they could remove enough carbon to
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equal all emissions from global aviation, all flights using jet
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fuels everywhere in the world. What's more, studies show that
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kelp forests give off biogenic aerosols, tiny air borne particles
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that come from living things that help clouds form. Coastal
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cloud cover reflects sunlight back into space. In its absence,
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the seas and soils are hotter, which also heats the air.
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There is more evaporation, and there are longer periods without rain.
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The ground becomes drier, making coastal woodlands more susceptible to wildfire.
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We can keep California cooler and keep it from burning.
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Von Hertzen said this can be done not in the
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distant future, but within the next ten years. That's because
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kelp can expand its coverage by eighteen inches per day.
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Some giant kelp grow at a daily rate of two
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To take in the full glory of kelp, I flew
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to a set of seaside towns near Eureka, roughly one
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hundred miles south of the Oregon border, that were playing
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host to the California Seaweed Festival, a two or three
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day event that pops up each year in different parts
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of the state. Festival, now in its sixth year, was
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co founded by biologist Janet Cubler, who spelled out the
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challenges and opportunities for KELP and a twenty twenty one
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paper in the Journal of the World Aquaculture Society. It's
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not just a conference, Kubler told me, it's a celebration
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of seaweed, not just as a food or a carbon sink,
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but all of its possibilities. Inside the festival's main venue,
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at Eureka's Warfinger Building, a diverse set of scientists, including
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indigenous leaders, was ready to point to their wall posters
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and chat about their research. Leaders of the Sunflower Star
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Lab were on hand to talk about recovery from the
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blob which brought about sea star wasting syndrome, all but
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killing off this keystone species, another natural predator of purple urchins.
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The stars, which stood in small tanks on display here,
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grow up to thirty nine inches wide when they are
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released near a celp forest. A slow motion chase scene ensues.
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Urchins sense danger from chemicals released by the stars and
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try to escape, but the stars are speedier. Finally, a
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star will clutch and consume an urchin outside, a bluegrass
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band called The Compost Mountain Boys played as attendees. Toward
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the Farmer's Market, a stand operated by Sunken Seaweed, a
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start up that skyrocketed out of San Diego, drew much
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of the attention. The table was staffed by its co founder,
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Tory Polizzi, who sold me a twelve dollars jar of kalafrikake,
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a local twist on Japanese style seasoning made from seaweed.
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The festival underscored the versatility of this underappreciated client solution.
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I was familiar with kelp based protein smoothies for humans,
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but I learned how sprinkling seaweed on cattle feed can
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help cows digest their food, reducing their methane emissions between
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forty and eighty percent. Kelp can also serve as an
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ingredient and biojegradable biopolymers, which are used in place of
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petroleum based plastics. In twenty twenty, a non profit called
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the Lonely Whale Foundation announced a one point two billion
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plastic innovation prize and partnership with tom Ford Beauty, a
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company founded by fashion designer Tom Ford, not by marine
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biologist Tom Ford, who runs the Bay Foundation. The top award,
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announced in twenty twenty three, went to a California company
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called Sway, which makes a seaweed based alternative to thin
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film plastic packaging. At the docks, I boarded a boat
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for a Humboldt Bay Harbor cruise. Out on the sparkling water,
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we spotted pelicans gliding in for a lunch of fish.
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The boat passed an aquatic farm established in twenty twenty
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that had produced more than three thousand pounds of bull
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kelp that year. On the cruise, a Los Angeles company
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called Blue Robotics was showing images captured by a remotely
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operated vehicle that can help tend kelp several hundred feet
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under water. At night, a party billed as the Seaweeds
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Speakeasy featured local beers made with kelp instead of malt,
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served along with seaweedy or d'euvs. I found a station
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serving mac and kelp and cheese that went down easy
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with the beer. The festival culminated at the marine lab
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of cow Poly Humboldt. Pulling on latex gloves, I stood
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beside a labbed table set with fresh ribbons of kelp
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and learned how to assess its reproductive health by isolating
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the tissue that holds its spores with the razor. I
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scraped a slimy layer off a blade, splashed it with iodine,
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and set the substance under a microscope. The batch held
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spores with excellent motility, the ability to move well on
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their own. Each spore grows into a microscopic organism, either
23:13
male or female. The males will release sperm into the water,
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and the females will release chemicals that help the sperm
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find their eggs. I left the festival feeling satisfied and
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dare I say optimistic, yet with some big unresolved questions.
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Where was this kelp work heading, How big could the
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movement really get? What kinds of signs would urge people
23:36
to take such solutions seriously? The last of these questions
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took on even more urgency for me in January, after
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winds up to one hundred miles an hour hit Los Angeles,
23:47
where I live. The gusts stoked flames on parched lands,
23:52
creating Southern California's most devastating winter fire in decades. The
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result death, devastation, and more than seventy five billion dollars
24:01
in damages. The average person may know the Earth is
24:05
warmer now than at any time in the past one
24:07
hundred thousand years, or that each year now sets a
24:10
global temperature record, but what happens under water is so
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rarely seen. Most people have no idea that seaweeds have
24:18
been around for a billion years, or that algae and
24:21
aquatic plants provide the planet with about half of its oxygen,
24:25
the other half coming from terrestrial plants. Most people don't
24:29
know that ocean water has already absorbed about a third
24:32
of humanity's excess carbon emissions, and that the resulting carbonic
24:36
acid disrupts the ocean's chemistry, leaving less calcium for the
24:40
hard shell casings of shell fish, or that cultivating kelp
24:44
serves as a giant pushback against this process. Most people
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don't know that seaweeds can be used to make natural,
24:51
low cost alternatives to plastics and fertilizers. The Chumash people
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know all of this. I met Paggling at Galita Beach
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near St. Santa Barbara to chat on a bench by
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the playground where her four year old was having a
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wonderful time. Pagaline pointed to seaweed that had washed ashore
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on the sand and described how the chumash had been
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gathering the stuff from beaches for centuries. She uses it
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as a fertilizer for her family's garden of corn, squash, beans, carrots,
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and zucchini. You can watch the plants really take off,
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she said. As we gazed out at the ocean. She
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lamented the loss. That's where our food was provided. Our
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staple areas are swimming and fishing, she said. Then came
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the pollution, the overfishing, the poor land and water management practices.
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Oil platforms are still visible to anyone driving north from
25:43
Los Angeles along Highway one O one. After a century
25:47
of drilling, Californians have now spent more than a decade
25:51
taking steps toward decommissioning the rigs. Still as intrusive as
25:55
the rigs once were, ecosystems have adapted around them. As
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with shipwrecks, the rigs are now habitats for arrays of
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marine life. That's how resilient nature can be. Even many
26:08
staunch environmentalists agree that the underwater structures should remain after
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they are no longer in use. Paggling spoke of the
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celebrations on the Chumash Reservation when the federal government approved
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the Chumashed Heritage National Marine Sanctuary and the outlook for
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leading restoration of nature along the coast. There are so
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many calp forest opportunities now, she said. It will take
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collaboration between indigenous and non indigenous groups. Yet she acknowledged
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that there have been few collaborations like this before. Lots
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of communities say they are for restoration, but there is
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often disagreement over how. When the Tomob crew reaches Lemieux,
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a crowd of people from the Chumash community and beyond
26:54
will welcome those who paddled all through the night. Next year,
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Pagling says the gathering will only be about honoring the past,
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it will also celebrate the possibility of a better future. Finally,
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ask Smithsonian question why is the Midwest covered with prairies
27:13
instead of forests? The answer from June when National Museum
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of Natural History the Midwestern prairies used to be forests.
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The shift likely started between twenty million and twenty eight
27:25
million years ago, and it accelerated during the last five
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million years. Possible reasons include a drier climate with more
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natural fires, as well as the appearance of larger animals.
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Herbivores such as elk and bison needed a complex digestive
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system housed in a large body to derive nutrition from grasses.
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These big animals also tended to form herds, which made
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it easier to defend themselves against predators while migrating long
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distances to stay fueled there, grazing played a role in
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preventing large trees from returning to the Midwest. This concludes
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readings from the Smithsonian magazine for today. Your reader has
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been Rebecca Shore. Thank you for listening, and have a
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great day.