The Myth of the 100-foot Whale

Blue whale off the California coast. (Photo: Erik Olsen)

Not So Big: How We Overstate the Length of the Blue Whale, Earth’s Largest Creature

One of the most extraordinary privileges of living in California, especially near the coast, is witnessing the annual arrival of blue whales. I’ve been at sea on several occasions when these giants surfaced nearby, and to see one in person, or even through my drone RC, is astonishing and unforgettable. I once had the rare and mind-blowing opportunity to swim with and film blue whales off the southern tip of Sri Lanka for a story I wrote and produced, an experience that will forever be seared into memory.

For decades, the blue whale has been celebrated as the largest creature ever to exist (Bigger than dinosaurs! True.), with many popular accounts claiming that these animals can reach lengths of 100 feet or more. Yet in all the videos, photographs, and encounters I’ve seen, not a single whale has come close to that. Still, article after article and documentary after documentary continues to repeat the claim that blue whales “reach 100 feet or more.” Nearly every whale-watching company in California repeats the claim, echoed endlessly across Instagram and TikTok.

But is it true? Most blue whales I’ve seen off the coast of California are half that size or maybe 2/3. It felt misleading to say so otherwise. And so I did a lot of digging: reading, reaching out to experts, poring over historical records, and the fact is that no single blue whale has ever been scientifically measured at 100 feet. Close, as you will soon read, but not 100 feet or more. Especially not off the coast of California.

This discrepancy not only distorts our understanding of these magnificent creatures, but also highlights the broader issue of how media can shape and sometimes mislead public perception of scientific facts.

Blue whale tail fluke in Sri Lanka. (Photo: Erik Olsen)

In other words: the perception that blue whales commonly reach lengths of 100 feet or more likely stems from a combination of historical anecdotes, estimation errors, and a tendency to highlight extreme examples.

All that said, the blue whale (Balaenoptera musculus) is a truly magnificent creature. Hunted nearly to extinction in the 17th to 19th centuries, the blue whale has staged a hopeful recovery in the last five decades, since commercial whaling was outlawed by the international community in 1966 (although some Soviet whale hunting continued into the early 1970s). And California, in particular, has been blessed with the annual appearance of the largest population of blue whales in the world, called the Eastern North Pacific population, consisting of some 2,000 animals. That population makes an annual migration from the warm waters of Baja California to Alaska and back every year. This is the group I’ve seen off Newport Beach.

These numbers are painfully, tragically small compared to what existed before commercial whaling began. Prior to that, it was estimated that there were some 400,000 blue whales on earth. 360,000 were killed in the Antarctic alone. (IMO: this stands as one of the most shameful acts in human history).

Another way to support us is to buy something from our California wildlife store.

The International Union for Conservation of Nature estimates that there are probably between 5,000 to 15,000 blue whales worldwide today, divided among some five separate populations or groups, including the Eastern North Pacific population. Many now swim so close to shore that an entire whale-watching industry has flourished along the California coast, especially in the south, with many former fishing boats converted into whale-watching vessels..

But back to size, or, more specifically, length: there are two credible references in scientific papers of blue whales that are near 100 feet. The first is a measurement dating back to 1937. This was at an Antarctic whaling station where the animal was said to measure 98 feet. But even that figure is shrouded in some suspicion. First of all, 1937 was a long time ago, and while the size of a foot or meter has not changed, a lot of record-keeping during that time is suspect, as whales were not measured using standard zoological measurement techniques (see below). The 98-foot specimen was recorded by Lieut. Quentin R. Walsh of the US Coast Guard, who was acting as a whaling inspector of the factory ship Ulysses. Sadly, there is scant detail available about this measurement and it remains suspect in the scientific community.

Blue whale in Sri Lanka. (Photo: Erik Olsen)

The second is from a book and a 1973 paper by the late biologist Dale W. Rice, who references a single female in Antarctica whose “authenticated” measurement was also 98 feet. The measurement was conducted by the late Japanese biologist Masaharu Nishiwaki. Nishiwaki and Rice were friends, and while both are deceased, a record of their correspondence exists in a collection of Rice’s papers held by Sally Mizroch, co-trustee of the Dale W. Rice Research Library in Seattle. Reached by email, Dr. Mizroch said that Nishiwaki, who died in 1984, was a very well-respected scientist and that the figure he cited should be treated as reliable.

According to Mizroch, who has reviewed many of the Antarctic whaling records from the whaling era, whales were often measured in pieces after they were cut up, which greatly introduces the possibility for error. That is likely not the case with the 98-foot measurement, which took place in 1947 at a whaling station in Antarctica where Nishiwaki was stationed as a scientific observer.

Blue whale (NOAA)

Proper scientific measurements, the so-called “standard method”, are taken by using a straight line from the tip of the snout to the notch in the tail flukes. This technique was likely not used until well into the 20th century, said Mizroch. In fact, it wasn’t until the 1940s that the use of a metal tape measure became commonplace. According to Dan Bortolotti, author of Wild Blue: A Natural History of the World’s Largest Animal, many of the larger whales in the whaling records — especially those said to be over 100 feet — were probably measured incorrectly or even deliberately exaggerated because bonus money was paid to whalers based on the size of the animal caught.

So, according to the best records we have, the largest blue whale ever properly measured was 98 feet long. Granted, 98 feet is close to 100 feet, but it’s not 100 feet, and it’s certainly not over 100 feet, as so many otherwise reputable references state.

So, setting aside the fact that so many sources say the blue whale has reached 100 feet or more, and that there is no scientific evidence proving this, a key question to ask is how large can whales become?

Blue whale from the National Oceanic and Atmospheric Administration

Most baleen whales are so-called lunge feeders. They open their mouths wide and lunge at prey like krill or copepods, drawing in hundreds of pounds of food at a time. Lunge-feeding baleen whales, it turns out, are wonderfully efficient feeders. The larger they become, the larger their gulps are, and the more food they draw in. But they also migrate vast distances, and oftentimes have to dive deep to find prey, both of which consume a large amount of energy.

A 2019 scientific paper in Science described how a team of researchers used an ocean-going Fitbit-like tag to track whales’ foraging patterns, hoping to measure the animals’ energetic efficiency, or the total amount of energy gained from foraging, relative to the energy expended in finding and consuming prey. The team concluded that there are likely ecological limits to how large a whale can become and that maximum size in filter feeders “is likely constrained by prey availability across space and time.” That is especially the case in today’s era, when overfishing and illegal fishing, including krill harvesting in Antarctica, have reduced the amount of prey available even in regions that used to be very prolific.

Whale fall off the California Coast (Ocean Exploration Trust)

John Calambokidis, a Senior Research Biologist and co-founder of Cascadia Research, a non-profit research organization formed in 1979 based in Olympia, Washington, has studied blue whales up and down the West Coast for decades. He told California Curated that the persistent use of the 100-foot figure can be misleading, especially when the number is used as a reference to blue whales off the coast of California.

The sizes among different blue whale groups differ significantly depending on their location around the globe. Antarctic whales tend to be much bigger, largely due to the amount of available food in cold Southern waters. The blue whales we see off the coast of California, Oregon, Washington and Alaska, are part of a different group from those in Antarctica. They differ both morphologically and genetically, and they consume different types and quantities of food. North Pacific blue whales, our whales, tend to be smaller and likely have always been so. Calambokidis believes that the chances any blue whales off the West Coast of the US ever reaching anything close to 100 feet is “almost non-existent”.

I emailed Regina Asmutis-Silvia, Executive Director North America of Whale and Dolphin Conservation, to ask about this discrepancy among so many seemingly authoritative outlets. She wrote: “While it appears biologically possible for blue whales to reach or exceed lengths of 100’, the current (and limited) photogrammetry data suggest that the larger blue whales which have been more recently sampled are under 80 feet.” Photogrammetry is the process of using several photos of an object — like a blue whale — to extract a three-dimensional measurement from two-dimensional data. It is widely used in biology, as well as engineering, architecture, and many other disciplines. Photogrammetry measurements are now often acquired by drones and have proven to be a more accurate means of measuring whale size at sea.

Antarctic whaling station.

Here’s a key point: In the early part of the 20th century and before, whales were measured by whalers for the purpose of whaling, not measured by scientists for the purpose of science. Again, none of this is to say that blue whales aren’t gargantuan animals. They are massive and magnificent, but if we are striving for precision, it is not accurate to declare, as so many articles and other media do, that blue whales reach lengths of 100 feet or more. Or to insinuate that this size is in any way common. This is not to say it’s impossible that whales grew to or above 100 feet, it’s that, according to the scientific records, none ever has.

A relevant point from Dr. Asmutis-Silvia about the early days of Antarctic whaling: “Given that whales are long-lived and we don’t know at what age each species reaches its maximum length, it is possible that we took some very big, very old whales before we started to measure what we were taking.”

In an email exchange with Jeremy Goldbogen, the scientist at Stanford who authored the study in Science above, he says that measurements with drones off California “have been as high as 26 meters” or 85 feet.

So, why does nearly every citation online and elsewhere regularly cite the 100-foot number? It probably has to do with our love of superlatives and round numbers. We have a deep visceral NEED to be able to say that such and such animal is the biggest or the heaviest or the smallest or whatever. And, when it comes down to it, 100 feet is a nice round number that rolls easily off the tongue or typing fingers.

All said, blue whales remain incredible and incredibly large animals, and deserve our appreciation and protection. Their impressive rebound over the last half-century is to be widely celebrated, but let’s not, in the spirit of scientific inquiry, overstate their magnificence. They are magnificent enough.

California Is a Nobel Powerhouse

You can keep your Oscars, Emmys, Grammys, and Tonys. Take your Pulitzers, Bookers, and Peabodys, too. Even the Pritzker and the Fields Medal don’t quite measure up. For me, nothing competes with the Nobel Prize as a symbol that someone has truly changed the world.

I’m not a scientist, but my mind lives in that space. Science, more than anything else, runs the world and reshapes it. This newsletter was born out of my fascination with how things work and the quiet mechanics behind the visible world and my love for all that California has to offer in the way of innovation and natural beauty. I love standing in front of something familiar and asking: why? how? what exactly is going on here? And nothing satisfies that intense curiosity more than science.

That said, I’ve never loved the word science. It feels cold and sometimes intimidating, as if it applies to people in lab coats and not to everyone else. I kinda wish there were a better word for that spirit of discovery that lives in all of us. Maybe it’s wonder. Maybe curiosity. I dunno. “Science” turns people off sometimes, unfortunately.

Whatever you call it, the Nobel Prize represents the highest acknowledgment of that pursuit. It is the world’s way of saying: this mattered. This changed something. And there are few places (if any) on Earth that can rival California when it comes to the number of people who have earned that honor.

This year, 2025, was no different. Three of the Nobel Prizes announced this week carried California fingerprints, adding to a tradition that stretches back more than a century.

The Nobel Prize in Physiology or Medicine came first. It went to Mary Brunkow, Shimon Sakaguchi, and Fred Ramsdell, the last of whom studied at UCLA and UC San Diego. (In epic California fashion, Ramsdell, who studied at UCLA and UC San Diego, didn’t even learn he’d become a Nobel laureate until after returning from a trip deep into the Wyoming wilderness, where he’d been out of contact with the outside world. What’s more Californian than that?) Their research on regulatory T cells explained how the immune system knows when to attack and when to stand down. Ramsdell’s discovery of a key gene that controls these cells has transformed how scientists think about autoimmune disease and organ transplantation.

Next came the Nobel Prize in Physics, awarded to John Clarke of UC Berkeley, Michel H. Devoret of UC Santa Barbara and Yale, and John M. Martinis of UC Santa Barbara (big shout out to UCSB!). Their award honored pioneering work that revealed how the strange laws of quantum mechanics can be seen in circuits large enough to hold in your hand. Beginning in Clarke’s Berkeley lab in the 1980s, the trio built superconducting loops that behaved like subatomic particles, “tunneling” and flipping between quantum energy states. Those experiments helped create the foundation for today’s quantum computers.

The Chemistry Prize followed a day later, shared by Susumu Kitagawa, Richard Robson, and Omar M. Yaghi of UC Berkeley for discoveries in metal–organic frameworks, or MOFs. These are crystalline materials so porous that a single gram can hold an entire roomful of gas (mind blown). MOFs are now used to capture carbon dioxide, filter water, and even pull drinking water from desert air. Yaghi’s Berkeley lab coined the term “reticular chemistry” to describe this new molecular architecture. His work has become one of California’s most important contributions to the climate sciences.

California Institute of Technology (Photo: Erik Olsen)

Those three announcements in as many days lit up California’s scientific community, has garnered many headlines and carried on a tradition that has made the state one of the world’s most reliable engines of Nobel-level discovery.

The University of California system now counts 74 Nobel Prizes among its faculty and researchers. 23 in physics and 16 in chemistry. Berkeley leads the list, with 26 laureates, followed by UC San Diego, UCLA, UC Santa Barbara, and UC San Francisco. Even smaller campuses, such as UC Riverside, have ties to winners like Barry Barish, who shared the 2017 Nobel in Physics for detecting gravitational waves.

Linus Pauling with an inset of his Nobel Prize in 1955 (Wikipedia – public domain)

Caltech, which I have written about extensively and is quite close to my own home, counts 47 Nobel laureates (faculty, alumni, or postdocs). Its history is the stuff of legend. In 1923, Robert Millikan won for measuring the charge of the electron. In 1954, Linus Pauling received the Chemistry Prize for explaining the nature of the chemical bond. He later won the Peace Prize for his anti-nuclear activism, making him the only person to win two unshared Nobels.

Stanford University sits not far behind, with 36 Nobel winners in its history and about 20 currently active in its community. From the development of transistors and lasers to modern work in medicine and economics, Stanford’s laureates have changed the modern world in ways that is impossible to quantify, but profound in their impact.

These numbers tell a clear story: since the mid-twentieth century, about one in every four Nobel Prizes in the sciences awarded to Americans has gone to researchers based at California institutions, an extraordinary concentration of curiosity, intellect, and ambition within a single state.

University of California Santa Barbara (Photo: Erik Olsen)

California’s Nobel dominance began early. In the 1930s, UC Berkeley’s Ernest Lawrence invented the cyclotron, a device that would transform physics and eventually medicine. Caltech, meanwhile, became a magnet for the world’s brightest physicists and chemists.

Over the decades, California’s universities turned their focus to molecular biology, biochemistry, and genetics. In the 1980s, the state’s physicists and engineers drove advances in lasers, semiconductors, and now, quantum circuits. And as biotechnology rose, San Diego and the Bay Area became ground zero for breakthroughs in medicine and life sciences. One of the great moments in genetics took place in Asilomar on the coast. 

Nobel Museum in Stockholm, Sweden (Photo: Erik Olsen)

This is all about more than geography and climate (although those are a big sell, for sure). California’s research institutions kick ass because they operate as ecosystems rather than islands. Berkeley physicists collaborate with engineers at Stanford. Caltech chemists trade ideas with biotech firms in San Diego. Graduate students drift between labs, startups, and national research centers like Lawrence Livermore and JPL. The boundaries between university and industry blur, with campuses like Stanford turning breakthrough discoveries into thriving commercial ventures (look how many of our big tech brains came out of Stanford). In California, research doesn’t end in the lab, it often turns into companies, technologies, and treatments that generate both knowledge and enormous economic value. Just look at AI today. 

Check out our Etsy store for cool California wildlife swag.

I think the secret is cultural. Over the years, I’ve lived on the East coast for almost two decades, and abroad for several as well, and nothing compares to the California vibe. California has never been afraid of big risks. Its scientists are encouraged to chase questions that might take decades to answer (see our recent story on just this idea). There’s an openness to uncertainty here that works well in the natural sciences, but can also be found in Hollywood, Silicon Valley and, of course, space exploration. 

When next year’s round of early morning calls comes from Stockholm, it is a good bet that someone in California will pick up. Maybe a physicist in Pasadena, a chemist in Berkeley, or a physician in La Jolla. Maybe they’ll pick up the phone in bed, maybe a text from a spouse while camping, or on a morning jog. That’s when a Swedish-accented voice tells them that the world has just caught up to what they’ve been quietly building for years.

Corals Revealed as Never Before Through a Groundbreaking New Microscope in California

A fluorescence image of a polyp from the coral Stylophora pistillata (side view) taken with the BUMP. (Credit: Or Ben-Zvi)

(We did a video about this story as well. We hope you watch! )

The story of corals in the modern age on this planet is one of near-total despair. I’ve done several stories on corals and have spent many hours diving reefs around the world, from the Mesoamerican Reef in Belize to the unbelievably robust and dazzling reefs in Indonesia. There are still some incredible places where corals survive, but they are becoming fewer and farther between. I don’t want to get too deep into all the statistics, but suffice it to say: scientists estimate that we have already lost about half of the world’s corals since the 1950s, and that number could rise to as much as 90 percent by 2050 if current rates of bleaching and die-offs continue.

What’s crazy is that we still don’t completely understand corals, or exactly why they are dying. We know that corals are symbionts with microscopic algae called zooxanthellae (pronounced zo-zan-THEL-ee). The corals provide cover, a place to live, and nutrients for the algae. In return, the algae provide sugars and oxygen through photosynthesis, fueling coral growth and reef-building. But when the planet warms, or when waters become too acidic, the relationship often collapses. The algae either die or flee the coral. Without that steady food source—what one scientist I interviewed for this story called “a candy store”—corals turn ghostly white in a process known as bleaching. If stressful conditions persist, they starve and die. 

But why? 

Scripps Institution of Oceanography in La Jolla (Photo: Erik Olsen)

“We still have no idea, physiologically, in the types of environments where bleaching predominates, whether the animal is throwing them out because it’s going to try to survive, or whether the little tiny plants say to the animal, ‘look, we can’t get along in this environment, so we got to go somewhere else’” says Dr. Jules Jaffe, an oceanographer at the Scripps Institution of Oceanography at the University of California, San Diego in La Jolla, California, and the head of the Jaffe Laboratory for Underwater Imaging

The Great Barrier Reef, once Earth’s largest living structure, has suffered five mass bleaching events since 1998, and vast stretches have become little more than graveyards of coral skeletons. The scale of this ecological disaster is almost unimaginable. And so scientists around the world are in a race to figure out what’s happening and how to at least try to slow down the bleaching events sweeping through nearly every major reef system.

An image of Montipora coral polyps taken with the BUMP. Each polyp has a mouth and a set of tentacles and the red dots are individual microalgae residing inside the coral tissue. (Photo: Or Ben-Zvi)

One place where scientists are making small strides is at the Jaffe Lab, which I visited with my colleague Tod Mesirow and where researchers like Dr. Jaffe and Dr. Or Ben-Zvi have developed a new kind of underwater microscope that allows them to get close enough to corals to actually see the algae in action. 

This is no small feat. Zooxanthellae are only about 5–10 microns across, about one-tenth the width of a human hair, and invisible to the naked eye. With the new microscope and camera system, though, they can be seen in astonishing detail. The lab has captured unprecedented behavior, including corals fighting with each other for space, fusing together, and even responding to invading algae.

When I first reported on this imaging system years ago, it was still in its early stages. At the time, it was known as the BUM for Benthic Underwater Microscope. Since then, the Scripps team has added a powerful new capability: a pulsing blue light that lets them measure photosynthesis in real time. They call it pulse amplitude modulated light or PAM, and so now the system is known as the BUMP. 

A field deployment of the BUMP in the Red Sea, where local corals were imaged and measured.  (Photo: Or Ben-Zvi)

Here’s how it works: blue excitation light stimulates the algae’s chlorophyll, which then re-emits some of that energy as red fluorescence. By tracking how much of this red fluorescence is produced, researchers can calculate indices of photochemical efficiency, essentially how well the algae are converting light into energy for photosynthesis. This doesn’t give a direct count of sugars or photons consumed, but it does provide a reliable window into the health and productivity of the algae, and by extension, the coral itself.

What’s crucial is that all of this imaging takes place in situ—right in the ocean, on living reefs—rather than in the artificial setting of an aquarium or laboratory.

Dr. Or Ben-Zvi, doctoral scholar at Scripps Institution of Oceanography (Photo: Erik Olsen)

New tools are essential if we’re going to solve many of our biggest problems, and it’s at places like Scripps in California where scientists are hard at work creating instruments that help us see the world in entirely new ways. “There’s so much to learn about the ocean and its ecosystems, and my own key to understanding them is really the development of new instrumentation,” says Jaffe.

Dr. Ben-Zvi gave us a demonstration of how the system works in an aquarium holding several species of corals, including Stylophora, a common collector’s coral. She showed us the remarkable capabilities of the camera-microscope, which illuminated and brought into crisp focus the tiny coral polyps along with their algal partners. On the screen we watched them in real time, tentacles waving as they absorbed the flashes of light from the BUMP, appearing, almost, as if they were dancing happily.

The Benthic Underwater Microscope PAM (BUMP) in action in the lab at Scripps Institution of Oceanography in La Jolla.
(Photo: Erik Olsen)

What this new tool allows scientists to do is determine whether corals may be under stress from factors like warming seas, pollution, or disease. Ideally, these warning signs are detected before the corals expel their zooxanthellae and bleach. Researchers are also learning far more about the everyday behavior of corals: something rarely studied in situ, directly in the ocean. 

That in-their-native-environment aspect of the work is crucial, because corals often behave very differently in aquariums than they do on wild reefs. That’s where this microscope promises to be a powerful tool: offering insights into how corals really live, fight, and respond to stress.

The view of La Jolla from the Scripps Institution of Oceanography (Photo: Erik Olsen)

Of course, what we do once we document a reef under stress is another matter. Dr. Ben-Zvi suggests there may be possibilities for remediation, though she admits it’s difficult to know exactly what those are. Perhaps reducing pollution, limiting fishing, or cutting ship traffic in vulnerable areas could help. But given that we seem unable—or unwilling—to stop the warming of the seas, these measures can feel like stopgaps rather than solutions. Still, knowledge is the foundation for any action, and this new tool is a breakthrough for coral imaging. If deployed widely, it could generate an invaluable dataset for researchers around the globe. The scientists behind it even hope to build multiple systems, perhaps commercializing them, to vastly expand the reach of this kind of monitoring.

But even Jaffe concedes it may already be too late: “Could a world exist without corals? Yeah, I think so,” he said. “It would be sad, but it’s going that way.”

All the same, the images the tool produces are breathtaking, and at the very least, they might jolt people into realizing that this is a crisis worth trying to solve. If we can’t, then future generations will be left only with these hauntingly beautiful images to remember the diverse and gorgeous animals that once flourished along the edges of the sea. 

A healthy coral reef in Indonesia (Photo: Erik Olsen)

Is that valuable? Yes, but not nearly as valuable as saving the living reefs themselves. Dr. Jaffe told us,

“I’m on a mission to help people feel empathy toward the creatures of the sea. At the same time, we need to learn just how beautiful they are. For me, the combination of beauty and science has been at the heart of my life’s work.”

His words capture the spirit of this research. The underwater microscope isn’t just a scientific instrument. It’s a lens into a hidden world, one that may inspire people to care enough to act before it’s gone. Too bad the clock is ticking so fast.

(We did a video about this story as well. We hope you watch! )

A Tiny California Seaweed Could Make a Big Dent in Livestock Methane

Flasks of Asparagopsis taxiformis growing at Scripps Institution of Oceanography. Researchers are studying this red seaweed for its potential to slash methane emissions from cattle when added in small amounts to their feed. (Photo: Erik Olsen)

Inside a long, brightly lit basement lab at the Scripps Institution of Oceanography at UC San Diego, a large aquarium filled with live corals sits against the wall, the vibrant shapes and colors of the coral standing out against the otherwise plain white surroundings. Nearby, in a side alcove, dozens of glass flasks bubble with aerated water, each holding tiny crimson clusters of seaweed swirling in suspension, resembling miniature lava lamps. These fragile red fragments, born in California and raised under tightly controlled conditions, are part of a global effort to harness seaweed to fight climate change.

Cattle and other ruminant livestock are among the largest contributors to methane emissions worldwide, releasing vast amounts of the gas through digestion and eructation. Burps, not farts. The distinction is not especially important, but it matters because critics of climate science often mock the idea of “cow farts” driving climate change. In reality, the methane comes primarily from cow burps, not flatulence.

But I digress. 

Cattle at Harris Ranch in California’s Central Valley, one of the largest beef producers in the United States. Livestock operations like this are a major source of methane emissions, a greenhouse gas more than 80 times as potent as carbon dioxide over a 20-year period. (Photo: Erik Olsen)

Globally, livestock are responsible for roughly 14 percent of all human-induced greenhouse gases, with methane from cattle making up a significant portion of that total. The beef and dairy industries alone involve more than a billion head of cattle, producing meat and milk that fuel economies but also generating methane on a scale that rivals emissions from major industrial sectors. Because methane is so potent, trapping more than 80 times as much heat as carbon dioxide over a 20-year period, the livestock industry’s footprint has become a central focus for climate scientists searching for solutions. 

Enter Jennifer Smith and her colleagues at the Smith Lab at Scripps in beautiful La Jolla, California. Their team is tackling urgent environmental challenges, from understanding coral die-offs to developing strategies that reduce greenhouse gas emissions, among them, the cultivation of seaweed to curb methane from cattle.  

The seaweed species is Asparagopsis taxiformis. Native to tropical and warm temperate seas and found off the coast of California, in fact right here off the coast in San Diego, it produces natural compounds such as bromoform that interfere with the microbes in a cow’s stomach that generate methane gas, significantly reducing the production of methane and, of course, it’s exhalation by the animals we eat. It turns out the seaweed, when added to animal feed can be very effective:  

Asparagopsis taxiformis, commonly known as red sea plume, a tropical red algae being studied for its ability to cut methane emissions from cattle. (Photo: Wikipedia)

“You need to feed the cows only less than 1% of their diet with this red algae and it can reduce up to 99% of their methane emissions,” said Dr. Or Ben Zvi, an Israeli postdoctoral researcher at Scripps who studies both corals and seaweeds.

Trials in Australia, California, and other regions have shown just how potent this seaweed can be. As Dr. Ben Zvi indicated, even at tiny doses, fractions of a percent of a cow’s feed, other studies have shown that it can reduce methane by 30 to 90 percent, depending on conditions and preparation. Such results suggest enormous potential, but only if enough of the seaweed can be produced consistently and sustainably.

“At the moment it is quite labor intensive,” says Ben Zvi. “We’re developing workflows to create a more streamlined and cost-effective industry.”

Which explains to bubbling flasks around me now. 

Scripps Institution of Oceanography at UC San Diego (Photo: Erik Olsen)

The Smith lab here at Scripps studies every stage of the process, from identifying which strains of Asparagopsis thrive locally to testing how temperature, light, and carbon dioxide affect growth and bromoform content. Dr. Ben Zvi is focused on the life cycle and photosynthesis of the species, refining culture techniques that could make large-scale cultivation possible. At Scripps, environmental physiology experiments show that local strains grow best at 22 to 26 °C and respond well to elevated CO₂, information that could guide commercial farming in Southern California.

The challenges, however, are considerable. Wild harvesting cannot meet demand, and cultivating seaweed at scale requires reliable methods, stable yields, and affordable costs. Bromoform content varies widely depending on strain and growing conditions, so consistency remains an issue. Some trials have noted side effects such as reduced feed intake or excess mineral uptake, and long-term safety must be established since we’re talking about animals that we breed and raise to eat.

“It’s still a very young area, and we’re working on the legislation of it,” says Ben Zvi. “We need to make it legal to feed to a cow that eventually we either drink their milk or eat their meat. We need for it to be safe for human consumption.” 

Dr. Or Ben Zvi (Photo: Erik Olsen)

And, of course, large-scale aquaculture raises ecological questions, from nutrient demands and pollution to the fate of volatile compounds like bromoform.

To overcome these obstacles, collaborations are underway. UC San Diego and UC Davis have launched a pilot project under the UC Carbon Neutrality Initiative to test production methods and carbon benefits. In 2024, CH4 Global, a U.S.-based company with operations in New Zealand and Australia that develops seaweed feed supplements to cut livestock methane, partnered with Scripps to design cultivation systems that are efficient, inexpensive, and scalable. Within the Smith Lab, researchers are continuing to probe the biology of Asparagopsis, mapping its genetics, fine-tuning its culture, and testing ways to maximize both growth and methane-suppressing compounds.

At a time when university-based science faces immense pressures, the Smith Lab at Scripps provides a glimpse of research that is making a real impact. The coral tanks against the wall belong to another project at the lab, and we have another story coming soon about the research that readers will find very interesting, but the bubbling flasks in the alcove reveal how breakthroughs often start with small details. In this case, the discovery that a chemical in a widely available seaweed could have such a dramatic, and apparently harmless, effect on the methane that animals make in their guts. These modest but powerful steps are shaping solutions to global challenges, and California, with its wealth of scientific talent and institutions, remains at the forefront. It is one of many other stories we want to share, from inside the labs to the wide open spaces of the state’s natural landscapes. 

California’s Precarious Future and the Promise—and Limits—of Desalination

Visibly low water conditions at Shasta Lake in Shasta County, on October 13, 2022.
Andrew Innerarity / California Department of Water Resources.

Water, water, every where, nor any drop to drink.  — Samuel Taylor Coleridge’s poem The Rime of the Ancient Mariner. 

The ocean covers about 70 percent of Earth’s surface and holds 96 percent of its water. But because it’s saturated with salt, it isn’t drinkable. Sailors have known this for centuries, and that’s a profound challenge for California, with more than 800 miles of coastline and a history of drought that has persisted for over two decades despite occasional relief from heavy rains.

Remember those rains?

The atmospheric rivers of 2024 in California briefly filled reservoirs and restored snowpack, but drought has already returned to parts of the state, underscoring the state’s precarious water future and fueling renewed debate over desalination as a long-term water solution.

The Los Angeles Rifer flows high following atmospheric river storms in 2024 (Photo: Erik Olsen)

Several regions facing severe drought have turned to desalination with notable success. Israel now supplies up to 40 percent of its domestic water through desalination and is widely recognized as a global leader in technological innovation. In the Gulf, countries like Saudi Arabia, the United Arab Emirates, Kuwait, and Qatar depend heavily on desalinated water, with the region producing roughly 40 percent of the world’s supply of desal. Saudi Arabia’s Ras Al-Khair plant, for example, is the largest hybrid desalination facility in the world. Australia has also invested heavily, with Adelaide’s desalination plant able to provide up to half of the city’s water and ramping up to full capacity during the 2024–2025 drought.

By contrast, California, the world’s fourth-largest economy, continues to struggle with recurring droughts despite some relief from those recent rains.

Many new projects are underway to recycle and store water, but desalination remains an important option that could play a larger role in how California manages supplies for its residents and farmers. For now, the state has only a handful of desalination plants, with just two operating at significant scale, leaving California far behind global leaders.

The Piggyback Yard rail site in Los Angeles, long used for freight operations, is now at the center of a proposal to transform the space into a massive stormwater capture and storage project. (Photo: Erik Olsen)

California will keep bouncing between wet and dry years, and that reality has pushed seawater and brackish-water desalination from a thought experiment into a real, if specialized, tool. It’s a big deal: The promise is reliable “drought-proof” supply. The tradeoffs are clear: high costs, heavy energy demands, and the challenge of careful siting. California has pushed the frontier of desalination technology, but it remains far from being an integral or dependable part of the state’s supply. Many observers doubt it ever will be.

But let’s take a look at where we are.

Desalination is already part of daily life in a few places. The 50-million-gallon-per-day Claude “Bud” Lewis Carlsbad Desalination Plant supplies roughly a tenth of the San Diego region’s potable demand, making it the largest seawater desalination facility in the United States. Water from Carlsbad is reliable during drought, but that reliability carries a premium: Recent public figures put its delivered cost in the low-to-mid $3,000s per acre-foot, higher than most imported supplies when those are plentiful. Even advocates frame the key tradeoff as price and energy intensity in exchange for certainty.

Claude “Bud” Lewis Carlsbad Desalination Plant (Photo courtesy of Carlsbad Desalination Project)

Rules matter as much as membranes. Since 2015, California has required new ocean desal plants to use the best available site, design, technology, and mitigation measures to minimize marine life mortality at intakes and to limit brine impacts at outfalls. These standards make facilities gentler on the ocean and they shape where plants can be built and what they cost. But it’s complicated.

The permitting bar is real, some say too onerous. In May 2022 the California Coastal Commission unanimously denied the proposed Huntington Beach seawater desalination plant after staff raised concerns about high costs, harm to marine life from an open-ocean intake, exposure to sea-level rise, and a lack of demonstrated local demand. That decision did not end desalination, but it clarified where and how it can pencil out. The same year, the Commission unanimously approved the smaller Doheny project in Dana Point because it uses subsurface intake wells and showed stronger local need and siting.

The Seawater Desalination Test Facility in Port Hueneme, Ventura. (Photo: John Chacon / California Department of Water Resources)

Doheny is frequently described as a late-2020s project, but its official timeline has slipped as partners and financing have taken longer to come together. That’s so California. The South Coast Water District has projected completion and operations in 2029, with key procurement milestones running through 2025. Given California’s regulatory climate, I’d say these dates are optimistic rather than bankable.

Elsewhere on the coast, the California American Water project for the Monterey Peninsula cleared a major hurdle in November 2022. Designed to add about 4.8 million gallons per day and pair with recycled water to replace over-pumping groundwater (a huge issue), it underscored desal’s role where other options are limited. In August 2025, the CPUC projected a 2050 supply deficit of 815 million gallons per year and cleared the way for construction to begin by year’s end. So, yeah. We’ll see.

Project site map of the Doheny Ocean Desalination Project (South Coast Water District)

Desalination is not only ocean-sourced. Several California systems quietly run on brackish water, which is less salty and cheaper to treat than seawater. Antioch’s brackish plant on the San Joaquin River is designed for about 6 million gallons per day to buffer the city against salinity spikes during drought. It was slated to come online this year, but operations have yet to begin (at least, I could not find any new info to this effect). Up the coast, Fort Bragg installed a small reverse-osmosis system in 2021 to deal with high-tide salt intrusion in the Noyo River during critically low flows, and it has piloted wave-powered desal buoys for emergency resilience.

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Santa Barbara’s Charles E. Meyer plant was reactivated in 2017 after years in standby and now functions as a reliability supply the city can dial into. In 2024 it contributed a meaningful slice of deliveries.

These are targeted, local solutions, not silver bullets, and that is the point.

Energy remains the biggest driver of desalination costs. Even with modern technology cutting usage to 2.5 to 4 kilowatt-hours per cubic meter, desal still requires far more power and therefore higher expense than water recycling or imported supplies. Beyond cost, desalination also brings added challenges, from greenhouse gas emissions tied to electricity use to the disposal of concentrated brine back into the ocean.

Santa Barbara’s Charles E. Meyer plant (City of Santa Barbara)

But the reality today is that the biggest additions to statewide water supply are coming from large-scale potable reuse, aka recycling. San Diego’s Pure Water program begins adding purified water to the drinking system in 2026 and scales toward about 83 million gallons per day by 2035. Metropolitan Water District’s Pure Water Southern California is planning up to roughly 150 million gallons per day at full build-out. These projects do not replace desal everywhere, but they change the calculus in big metro areas by creating local, drought-resilient supplies with generally lower energy and environmental footprints.

With most desalination projects carrying steep costs, success may hinge on innovation. Several new approaches now being tested in California waters are showing early promise. In 2025, OceanWell began testing underwater desalination pods in a reservoir near Malibu. These cylindrical units are designed to test how membranes perform when microorganisms are present in the water, since bacteria and algae can grow on the surfaces and form biofilms that clog the system.

A drawing of OceanWell’s underwater desalination pod system (OceanWell)

The longer-term vision is “water farms” made up of subsea pods tethered 1,300 feet down, where natural hydrostatic pressure does much of the work. Each pod could produce up to a million gallons of fresh water per day with roughly 40 percent less energy than a conventional onshore plant. Because the brine would be released gradually at depth, the approach could also reduce ecological impacts. OceanWell has said its first commercial-scale project, called Water Farm 1, could be operating by 2030 if tests and permitting go as planned. It’s interesting, for sure, but in the end, we’re talking long-shot here.

Big picture, desalination works best as a specialty tool—it’s not the answer everywhere, but it can be a game-changer in the right spots. Think coastal towns with little groundwater, islands or peninsulas with fragile aquifers, or inland areas that get hit with salty water now and then. California’s rules now push projects toward gentler ocean intakes and better brine disposal, but the real strategy is a mix: conservation, stormwater capture, groundwater banking, recycled water, and just the right amount of desal. Those huge atmospheric river storms are not predictable. Who knows if we’ll get another next year or the year after that? The next drought will come, and the communities that invested in a full toolkit will be the ones that hold up the best.

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Bring Human Exploration Back to California’s Deep Ocean

Launching a Triton 3300/3 submersible from a scientific support ship in the Bahamas. (Photo: Erik Olsen)

It’s time for California to put people back in the deep. A human-occupied submersible belongs in California waters, and we’ve waited long enough.

For decades, the state had a strong human-occupied submersible presence, from Navy test craft in San Diego to long-serving civilian science HOVs like the Delta. Those vehicles have been retired or relocated, leaving the West Coast without a single home-based, active human-occupied research submersible (I am not counting OceanGate’s Titan sub for numerous reasons, like the fact it was based in Seattle, but foremost is it was not “classed,” nor was it created for scientific use). Restoring that capability would not only honor California’s legacy of ocean exploration but also put the state back at the forefront of direct human observation in the deep sea. The time has come.

Side note: I’ve had the rare privilege of diving beneath the waves in a submersible three times in three different subs, including one descent to more than 2,000 feet with scientists from the Woods Hole Oceanographic Institution. Without exaggeration, it stands among the greatest experiences of my life.

The United States once had a small fleet of working research HOVs. Today it has essentially one deep-diving scientific HOV in regular service: Alvin, operated by Woods Hole Oceanographic Institution (WHOI) for the National Deep Submergence Facility. Alvin is magnificent, now upgraded to reach 6,500 meters, but it is based on the Atlantic (in Massachusetts) and scheduled years in advance at immense cost.

The human-occupied submersible Alvin surfaces during the 2004 “Mountains in the Sea” Expedition, returning from a dive to explore deep seamount habitats teeming with corals, sponges, and other rarely seen marine life. (Photo: NOAA, Public Domain)

It helps to remember how we got here. The Navy placed Alvin in service in 1964, a Cold War investment that later became a pillar of basic research, investigating hydrothermal vents, shipwrecks and underwater volcanoes, among many, many other accomplishments. Over six decades of safe operations, Alvin has logged thousands of dives and undergone multiple retrofits, each expanding its depth range. Now rated to 6,500 meters, it can reach 98 percent of the ocean floor. WHOI’s partnership model with the Navy and universities shows exactly how public investment and science can reinforce each other. But Alvin is based on the East Coast: all that capability, history, and expertise is thousands of miles away. California needs its own Alvin. Or something even better…and perhaps cheaper. Though by cheaper I do not mean less safe.

For a time, California actually had multiple HOVs. The Navy fielded sister craft to Alvin, including Turtle and Sea Cliff. Both Turtle and Sea Cliff spent their careers with Submarine Development Group ONE in San Diego. Turtle was retired in the late 1990s, and Sea Cliff, launched in 1968 and later upgraded for greater depths, also left service by the end of that decade, ending the Navy’s home-ported HOV presence on the West Coast.

On the Atlantic side, Harbor Branch’s two Johnson Sea Link HOVs supported science and search-and-recovery work for decades before the program ended in 2011 due to funding constraints and shifting research priorities. I’ve interviewed renowned marine biologist Edith Widder several times, and she often speaks about how pivotal her dives in the Johnson Sea Link submersibles were to her career studying animal bioluminescence.

“Submersibles are essential for exploring the planet’s largest and least understood habitat, ” Widder told me. “A human-occupied, untethered submersible offers an unmatched window into ocean life, far surpassing what remotely operated vehicles can provide. ROVs, with their noisy thrusters and blazing lights, often scare away marine animals, and even the most advanced cameras still can’t match the sensitivity of the fully dark-adapted human eye for observing bioluminescence.”

Harbor Branch Oceanographic Institution’s Submersible “Johnson SeaLink” (Wikipedia)

In the central Pacific, the University of Hawaiʻi’s HURL operated Pisces IV and V for much of the 2000s and 2010s, then suspended operations amid funding and ship transitions. Through attrition and budget choices, the working U.S. fleet shrank from a handful to essentially one deep-diving research HOV today.

Manned submersibles are costly to build and operate, and they demand specialized crews, maintenance, and support ships or platforms. It’s easy to list reasons why California shouldn’t invest in a new generation of human-occupied subs. But that mindset has kept us out of the deep for far too long. It’s time to turn the conversation around and recognize why having one here would be a transformative asset for science, education, and exploration.

The Seacliff and Turtle submersibles (Photo: U.S. Naval History and Heritage Command photo. Public Domain)

California’s own human-occupied sub legacy is short, but notable. In addition to the Navy submersibles noted above, the Delta submersible, a compact, ABS-class HOV rated to about 1,200 feet, operated from Ventura and later Moss Landing, supporting dozens of fishery and habitat studies from the Southern California Bight to central California. Built by Delta Oceanographics in Torrance, Delta dives in the mid-1990s produced baseline data that still underpin rockfish management, MPA assessments, and predictive habitat maps. The sub’s ability to place scientists directly on the seafloor allowed for nuanced observations of species behavior, habitat complexity, and human impacts that remote tools often miss. Many of these datasets remain among the most detailed visual records of California’s deeper reef ecosystems.

The Monterey Bay Aquarium Research Institute (MBARI) operates a world-class research fleet with a robust remotely operated vehicle (ROV) program, but no human-occupied vehicle—a strategic decision the institute made years ago in favor of robotics over direct human dives. (Photo: Erik Olsen)

In the late 1990s, the program shifted north to Moss Landing, where it was operated in partnership with the Monterey Bay Aquarium Research Institute (MBARI) and other institutions. At the time, MBARI was still in the early years of exploring human-occupied vehicles, like Bruce Robison’s experience piloting the Deep Rover HOV in Monterey Canyon in 1985. To many at MBARI, human occupancy in submersibles began to seem more like a luxury than a necessity. If the goal was to maximize scientific output and engineering innovation, remotely operated vehicles offered longer bottom times, greater payload capacity, and fewer safety constraints. That realization drove MBARI to invest heavily in ROV technology, setting the stage for a long-term move away from human-occupied systems.

Which leads us to the present moment: California’s spectacular coast faces mounting environmental threats, just as public interest in ocean science wanes. And yet, we have no human-occupied research submersible, no way for scientists or the public to directly experience the deep ocean that shapes our state’s future.

The Delta submersible, once a workhorse of California’s deep-sea research with over 5,800 dives, operated from Ventura and later Moss Landing between the 1980s and 2000s. Sold in 2011 in a non-functional state, it remains out of service—symbolizing the end of the state’s home-ported human-occupied submersible era.

Look, robots are incredible. MBARI’s ROVs and AUVs set global standards, and they should continue to be funded and expanded. But if you talk to veteran deep-sea biologists and geologists, they will tell you that being inside the environment changes the science.

Dr. Adam Soule, chief scientist for Deep Submergence at the Woods Hole Oceanographic Institution (WHOI) agrees, “Having a human presence in the deep sea is irreplaceable. The ability for humans to quickly and efficiently process the inherently 3D world around them allows for really efficient operations and excellent sampling potential. Besides, there is no better experience for inspiring young scientists and for ensuring that any scientist can get the most out of unmanned systems than immersing themselves in the environment.”

Some of our most prominent voices are also speaking out about the need to explore the ocean. I recently produced an hour-long episode of the PBS science program NOVA and one episode was about the new generation of submersibles being built right now by companies like Florida-based Triton Submarines. I had the privilege of talking to filmmaker and ocean explorer James Cameron, who was adamant that human participation in ocean exploration is critical to sustaining public interest and political will.

“The more you understand the ocean, the more you love the ocean, the more you’re fascinated by it, and the more you’ll fight to protect it,” Cameron told me.

The author with James Cameron in front of his submersible the Deepsea Challenger. (Erik Olsen)

Human eyes and brains pick up weak bioluminescence out of the corner of vision, pivot to follow a squid that just appeared at the edge of a light cone, or decide in the moment to pause and watch a behavior a diving team has never seen before. NOAA’s own materials explain the basic value of HOVs this way: you put scientists directly into the natural deep-ocean environment, which can improve environmental evaluation and sensory surveillance. Presence is a measurement instrument.

California is exactly where that presence would pay off. Think about Davidson Seamount, an underwater mountain larger than many national parks, added to the Monterey Bay National Marine Sanctuary because of its ancient coral gardens and extraordinary biodiversity. We know this place mostly through ROVs, and we should keep using them, but a California HOV could carry sanctuary scientists, MBARI biologists, and students from Hopkins Marine Station or Scripps into those coral forests to make fine-scale observations, sample with delicacy, and come home with stories that move the public. Put a student in that viewport and you create a career. Put a donor there and you create a program.

A time-lapse camera designed by MBARI engineers allowed researchers to observe activity at the
Octopus Garden between research expeditions. (Photo: MBARI)

Cold seeps and methane ecology are another natural fit. Off Southern California and along the borderlands there are active methane seep fields with complex microbial and animal communities. Recent work near seeps has even turned up newly described sea spiders associated with methane-oxidizing bacteria, a striking reminder that the deep Pacific still surprises us. An HOV complements ROV sampling by letting observers linger, follow odor plumes by sight and instrument, and make rapid, in-situ decisions about fragile communities that are easy to miss on video. That kind of fine-grained exploration connects directly to California’s climate priorities, since methane processes in the ocean intersect with carbon budgets.

There are practical use cases all over the coast. A California HOV could support geohazard work on active faults and slope failures that threaten seafloor cables and coastal infrastructure. It could conduct pre- and post-event surveys at oil-and-gas seep sites in the Santa Barbara Channel to ground-truth airborne methane measurements. It could document deep-water MPA effectiveness where visual census by divers is impossible. It could make repeated visits to whale falls, oxygen minimum zone interfaces, or sponge grounds to study change across seasons.

An autonomous underwater craft used to map DDT barrels on the seafloor off California.
(Photo: Scripps Institution of Oceanography at U.C. San Diego)

It could also play a crucial role in high-profile discoveries like the recent ROV surveys that revealed thousands of corroding barrels linked to mid-20th-century DDT dumping off Southern California. Those missions produced stark imagery of the problem, but a human-occupied dive would have allowed scientists to make on-the-spot decisions about barrel sampling, trace-chemical measurements, and sediment core collection, as well as to inspect surrounding habitats for contamination impacts in real time. The immediacy of human observation could help shape quicker, more targeted responses to environmental threats of this scale.

And it’s not just the seafloor that matters. Some of the most biologically important parts of the ocean lie well above the bottom. The ocean’s twilight zone, roughly 200 to 1,000 meters deep, is a vast, dimly lit layer that contains one of the planet’s largest reservoirs of life by biomass. (My dive with WHOI was done to study the ocean’s twilight zone). Every day, trillions of organisms participate in the planet’s largest migration, the diel vertical migration, moving up toward the surface at night to feed and returning to depth by day. This zone drives global carbon cycling, supports commercial fish stocks, and is home to remarkable gelatinous animals, squid, and deepwater fishes that are rarely seen in situ.

Launching the Triton 3300/3 (Photo: Erik Olsen)

The Triton 3300/3’s 1,000-meter depth rating (I’ve been in one twice) puts the entire twilight zone within reach, enabling direct observation of these daily movements, predator-prey interactions, and delicate species that often disintegrate into goo in nets. Human presence here allows scientists to make real-time decisions to follow unusual aggregations, sample with precision, and record high-quality imagery that captures how this midwater world works, something uncrewed systems alone rarely match.

It could even serve as a classroom at depth for carefully designed outreach dives, giving educators footage and first-person accounts that no livestream can quite match. Each of these missions is stronger with people on site, conferring, pointing, deciding, and noticing.

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While Monterey Bay would be a natural fit because of MBARI, Hopkins, and the sanctuary’s deepwater treasures, Southern California could be just as compelling. Catalina Island, with its proximity to submarine canyons, coral gardens, and cold seeps of the Southern California Bight, offers rich science targets and the existing facilities of USC’s Wrigley Marine Science Center. Los Angeles or Long Beach would add the advantage of major port infrastructure and a vast urban audience, making it easier to combine high-impact research with public tours, donor events, and media outreach. And San Diego with its deep naval history, active maritime industry, Scripps Institution of Oceanography, and proximity to both U.S. and Mexican waters, could serve as a southern hub for exploration and rapid response to discoveries or environmental events. These regions could even share the vehicle seasonally: Monterey in summer for sanctuary work, Catalina/LA or San Diego in winter for Southern California Bight missions, spreading both benefits and funding responsibility.

The author in front of the Triton 3300/3 in the Bahamas (Photo: Erik Olsen)

For budgeting, a proven benchmark is the Triton 3300/3, a three-person, 1,000-meter (3,300-foot) human-occupied vehicle used widely in science and filming. New units are quoted in the four to five million dollar range, with recent builds coming in around $4–4.75 million depending on specifications. Beyond the vehicle, launch and recovery systems such as a 25–30-ton A-frame or LARS and the deck integration required for a suitable support ship can run into the high six to low seven figures. Modern acrylic-sphere subs like the Triton are designed for predictable, minimized scheduled maintenance, but budgets still need to account for annual surveys, battery service, insurance, and ongoing crew training. Taken together, a California-based HOV program could be launched for an initial capital investment of roughly $6–7 million, with operating budgets scaled to the number of missions each year. So, not cheap. But doable for someone of means and purpose and curiosity. See below.

Who would benefit if California restored this capability? Everyone who already works here. MBARI operates a world-class fleet of ROVs and AUVs but has no resident HOV. Scripps Institution of Oceanography, Hopkins Marine Station, and USC’s Wrigley Marine Science Center train generations of ocean scientists who rarely get the option to do HOV work without flying across the country and waiting for a slot. NOAA and the sanctuaries need efficient ways to inspect resources and respond to events. A west-coast human-occupied research submersible based in Monterey Bay, Catalina, Los Angeles, or San Diego would plug into ship time on vessels already here, coordinate with ROV teams for hybrid dives, and cut mobilization costs for Pacific missions.

A new Triton 660 AVA submersible slips into the turquoise waters of the Bahamas, beginning its first voyage. Built for dives to 660 feet (200 meters), it offers passengers a front-row seat to reefs, shipwrecks, and marine life far beyond normal scuba limits, making it an ideal draw for high-end tourism. (Photo: Erik Olsen)

What would it take? A benefactor and a compact partnership. California has the donors (hello, curious billionaires!), companies, and public-private institutions to do this right. A philanthropic lead gift could underwrite acquisition of a proven, classed HOV and its support systems, while MBARI, Scripps, or USC could provide engineering, pilots, and safety culture within the UNOLS standards that govern HOV operations. No OceanGates. Alvin’s long record shows the model. Add a state match for workforce and student access, and a sanctuary partnership to guarantee annual science priorities, and you have a durable program that serves research, stewardship, and public engagement.

Skeptics will say that robots already do the job. They do a lot of it. They do not do all of it. If the U.S. is content to have only one deep research HOV based on the opposite coast, we will forego the unique perspectives and serendipity that only people bring, and we will keep telling California students to wait their turn or watch the ROV feed from their laptops or phones. California can do better. We did, for years, when the Delta sub spent long seasons quietly counting fish and mapping habitats off Ventura and the Channel Islands. Then that capability faded. If we rebuild it here, we restore a missing rung on the ladder from tidepools to trenches, and we align the state’s science, climate, and education missions with a tool that is both a laboratory and a conversion experience.

The author at more than 2000 feet beneath the surface of the ocean. (Photo: Erik Olsen)

Start with a compact, 1,000-meter-class HOV that can work daily in most of California’s shelf and slope habitats. Pair it with our ROVs for tandem missions and cinematography of the sub and its occupants in action. Commit a share of dives to student and educator participation, recorded and repackaged for museums and broadcast. Reserve another share for rapid-response science at seeps, landslides, unusual biological events, or contamination crises like the DDT dumpsite. Build a donor program around named expeditions to Davidson Seamount, Catalina’s coral gardens, and the Channel Islands. Then, if the community wants to go deeper, plan toward a second vehicle or an upgrade path. The science is waiting. The coast is ready. And the case is clear. California should restore its human-occupied submersible fleet.

How California Has Revived Its Groundfish Fisheries

How Smart Policy and Collaboration Brought Groundfish Back From the Brink

Vermillion Rockfish scientific illustration

Recently, I wrote a more personal essay than I usually would, one in which I reflected on the state of overfishing globally and the broader exploitation of our oceans.I hoped to draw attention to the new National Geographic documentary Oceans, featuring David Attenborough, which paints a broad and dire picture of the heath of the oceans and global fisheries…and it didn’t even cover deep sea mining which is a whole other megillah.

I’ve been following ocean conservation issues for decades, I’ve done numerous stories on the subject for major publications, and I’m deeply aware of the many threats facing the sea. These challenges extend to human society, too. Climate change, pollution, political instability, and species loss are just a few of the crises that fill our doom-scrolling feeds every day.

But not everything is lost.

Vermilion rockfish. (Photo: Robert Lee/NOAA)

Despite the scale of these problems, there are reasons for hope. Around the world, we are beginning to better manage some of our natural resources. There is growing awareness about how to extract from the planet in ways that do not destroy it. Slowly, we are learning how to sustain a growing, hungry population without collapsing the ecosystems we rely on. At least, that’s the hope. If you look around a bit, there are a few positive signs. I cited California’s Marine Protected Area program, but there are others.

Another particularly hopeful development is unfolding just off the coast of California.

The story of groundfish in California and the West Coast is one of collapse, struggle, rebirth, as well as evolving policy. Following passage of the Magnuson-Stevens Fishery Conservation and Management Act in 1976, which was supposed to help the fishery by banning foreign commercial fishing, between 1976 and 1979, the West Coast groundfish fleet tripled in size, growing from about 300 to nearly 1,000 vessels. New technologies made those boats far more effective. By the mid-1980s, about half the fleet could electronically track their fishing paths and return to the same productive grounds again and again. Sophisticated fishfinders like the “Chromascope” gave vessels an unprecedented edge.

A fishermen tending a groundfish trawl net off the coast of Oregon in 2019. (Photo: John Rae/NOAA)

Groundfish catch soared. In 1976, domestic harvests (excluding Pacific whiting) totaled around 57,000 tons. By 1982, that number had more than doubled to 119,000 tons. Rockfish, barely counted in the earlier fishery, made up more than 40,000 tons of the catch by that year alone.

But the science hadn’t caught up.

Fishery managers at the time didn’t fully understand how slowly groundfish grow, how long they live, or how vulnerable they are to overfishing. As a result, catch limits were set too high. The boom quickly gave way to collapse.

In the late 1990s and early 2000s, rockfish, bocaccio, Pacific ocean perch and other deep‑dwelling species teetered on collapse. Overfishing, excessive trawling, and habitat damage from bottom nets stripped populations across hundreds of miles of West Coast shelf. Regulators sounded the alarm and declared fishery disasters.

Sea bass in a California kelp forest (Photo: Erik Olsen)

Kenneth Weiss wrote in the Los Angeles Times, “Behind the sweeping action is a reluctant realization that the vast ocean has limits and cannot, as was long believed, provide an inexhaustible supply of fish.” Ya think?

To halt the decline, Congress and managers took bold, controversial steps. In 2003 a $46 million vessel‐buyback reduced the commercial trawl fleet by one‑third; by 2011 only about 108 vessels remained. That same year, the Pacific Fishery Management Council launched the groundbreaking Trawl Catch Share Program: individual fishing quotas based on historical catch and mandatory onboard observers. Within a year, discard rates plummeted from roughly 25 percent to below 5 percent.

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In fact, California law explicitly prohibits bottom trawling in its state waters except under very limited conditions. Fish and Game Code § 8841 makes bottom trawling unlawful in state ocean waters unless a state commission determines that it is sustainable and low-impact. According to NOAA, commercial bottom trawling is only permitted within the California Halibut Trawl Grounds (CHTG), a small coastal zone from roughly 1 to 3 nautical miles offshore between Point Arguello and Point Mugu.

Santa Cruz Island in California’s Channel Islands (Photo: Erik Olsen)

There are gear restrictions, including bans on roller gear larger than eight inches and a requirement for bycatch reduction devices in shrimp and prawn trawl fisheries. Bycatch is nothing but pure waste, bordering on evil, and reducing it or stopping altogether should be a goal. The state also pushes more sustainable gear types and has phased out new permits for trawlers.

At the same time, an extensive system of area closures was put in place. As the documentary points out, if you protect a habitat, it can recover, and we’ve seen that in places like the Channel Islands. Since the early 2000s, Rockfish Conservation Areas and Cowcod Conservation Areas have helped protect critical habitat. Then, in 2020, new federal rules expanded essential fish habitat protections, closing nearly 90 percent of the seafloor off California, Oregon, and Washington to bottom trawling.

Fast forward: these measures have worked! By the mid‑2010s, most of the over‑90 managed groundfish stocks were recovering or rebuilt, some years ahead of earlier projections. Pacific ocean perch, for instance, had been declared rebuilt in 2017 after 17 years under rebuilding plans. The fishery earned sustainability certification from the Marine Stewardship Council in 2014. Today, only yelloweye rockfish remains overfished, with rebuilding projected by 2029.

According to John Field, who leads the Fisheries and Ecosystem Oceanography Team at NOAA’s Southwest Fisheries Science Center, this turnaround didn’t happen by accident. “The fleet, the scientists, the managers, and everyone else saw there was a serious problem, and worked together to make difficult choices and rebuild populations,” Field told California Curated. “The solution required restructuring the fishery to conserve the species, with many tough years for the fleet. Although the groundfish fishery still faces many challenges, most populations are thriving, market demand is recovering, and there is more domestic seafood on American dinner plates.”

Equipment and methods have evolved. Vessels switched from race‑to‑fish trawls to quota‑based systems, often fishing more selectively using non‑trawl fixed gear, longline, pots, hook‑and‑line for sablefish and flatfish. Electronic monitoring and observer programs help track catches closely (you gotta have enforcement). 

Not all this has been smooth sailing. The shift to quotas and catch shares was controversial: many fishermen struggled with limited quotas, economic hardship, and uncertainty. Communities dependent on processors shrank as processors closed or consolidated. Some fishermen under‑caught allowable species to avoid hitting rockfish caps. Environmental groups have cautiously welcomed reopenings, but some expressed concerns that habitat recovery might still be fragile.

A ranger patrol boat off the coast of the Channel Islands in California (Photo: Erik Olsen)

So, looking back (and forward): policies over the past two decades, from trawl‐fleet reduction, gear rules, catch shares, quotas, habitat closures and strict rebuilding plans, not to mention MPAs, have turned the tide. Stocks are rebounding, many fisheries are sustainable, and management of the system is reviewed and changed if needed through amendments every two years. Of course, climate change and warming seas could render all this moot, so there’s still an element of keeping ones fingers crossed as we move forward.

This kind of drastic change takes time. And courage. And persistence. The long arc of recovery shows how science‑based regulation can bring back health to ocean ecosystems, and opportunity to coastal communities. Much of this work happens out of sight, in deep water and policy meetings alike, but its impact reaches every one of us: on our plates, in our economies, and in the resilience of the planet we all share.