TRANSCRIPT Reinventing the Eel

This is a transcript of the Gastropod episode, Reinventing the Eel, first released on May 17, 2022. It is provided as a courtesy and may contain errors.

JOHN TAYLOR: See, that’s all blue right there.


TAYLOR: A little head sticking out.

GRABER: Oh yeah, there they are.

NICOLA TWILLEY: (laughing) I got one! I got him! Hello my friend. Look at this guy. Poor little dude, I’m going to let you go. Don’t worry.

TWILLEY: Oh, he’s so little. He is…


TWILLEY: …going for it.

GRABER: Oh, yes. He’s like, let me back.

TWILLEY: I’m sorry, my friend. You’re going to go just as soon as you’ve starred in a couple of photos. You’re famous!

GRABER: Okay, swim well!

TWILLEY: Be free!


GRABER: Fly away!

GRABER: You might be wondering what we were so excited to manhandle — Nicky to my great shock had plunged her hands into a cold Maine river and caught a tiny nearly see-through baby eel! And then let it go. That’s right, this episode is all about eels, you’re listening to Gastropod, the podcast that looks at food through the lens of science and history, I’m Cynthia Graber—

TWILLEY: And I am Nicola Twilley, surprisingly gifted catcher of baby eels with my bare hands. Another skill to add to my resume.

GRABER: Today,you might think that eels mostly belong on a sushi menu. But eels have actually been an important source of food all around the world for thousands of years. And maybe they should even be part of our traditional Thanksgiving dinner.

TWILLEY: That’s if you can afford them. Those little teeny tiny baby eels I was scooping out of the water — they are actually one of the most expensive fish in the world on a per pound basis. Yes, this episode does involve suitcases full of cash.

GRABER: But also it involves Freud’s search for testicles, specifically eel testicles. Those remained a mystery for a long long time, and there are still mysteries today that have to do with eel sex.

TWILLEY: Really everything eel-related is bizarre and fascinating and bizarrely fascinating, and we have the scoop.

GRABER: As well as a visit to America’s only eel farm! This episode is supported in part by the Alfred P. Sloan Foundation for the Public Understanding of Science, Technology, and Economics. Gastropod is part of the Vox Media Podcast Network, in partnership with Eater.

TWILLEY: And before we grab hold of those slippery eels, we wanted to tell you about Whetstone Radio Collective. They’re a network of podcasts all about food — great storytellers representing people and places at the origin of food. Their shows are deliciously subversive and just a great listen. Check out South Asian food stories in Bad Table Manners, the stories and histories of African American cuisine and foodways in Setting the Table; Indigenous foodways in The Spirit Plate; and more. Check out Whetstone Radio Collective wherever you get your podcasts.


PATRIK SVENSSON: In natural science, they even talk about the eel question as one of the hardest scientific questions to answer.

SVENSSON: It’s a mysterious creature and it’s a creature that has been very, very hard to understand.

SVENSSON: And that’s also why it’s fascinating,

GRABER: Patrik Svensson is really fascinated by eels, so much so that he wrote an entire book about them. It’s called The Book of Eels. And his love affair began when he was quite young.

SVENSSON: Well, I grew up fishing for eels, during my whole childhood together with my father. Late summer nights down by a small river in the southern part of Sweden.

SVENSSON: Just my father and myself, always just the two of us together.

SVENSSON: My father told me, down on those nights, about the eel being a very mysterious creature and he told me about the eel going through changes and metamorphoses. And he told me about the Sargasso Sea, where every eel is born and it sounded like a fairytale place for me.

SVENSSON: And, it’s a lifelong fascination that started right there.

TWILLEY: We will be coming back to this fairytale place, the Sargasso Sea, but that’s a relatively recent stop in the story of the human eel relationship. We should really start with some basic getting to know you stuff: an eel is a fish, and I hate to be judgemental but it’s a pretty weird looking one.

SVENSSON: It’s… snake-like and it moves like a snake and it’s very slimy. And that’s also why many people think they’re actually quite disgusting. And people are afraid of them and they don’t want to touch them or have anything to do with them.

GRABER: But an eel is not a snake. Or a reptile at all. As we said, it’s a fish.

TWILLEY: And not just any fish — for many people in many places for most of human history, it was *the* fish.

SVENSSON: The eel fishing has been important in, in many parts of Europe and in the Southern part of Sweden, where, where I’m from, it’s been a very strong and important tradition to fish for eels.

TWILLEY: Regularly, when archaeologists are excavating rubbish dumps in Germany and northern Europe from the middle ages, they find that fully half the fish bones in the dump are from eels. People were eating a lot of eel.

GRABER: Eels were even used as currency at times in parts of Europe. In England, you could pay your rent in eels.

TWILLEY: The village where I grew up, Byfleet — in the year 1086, according to the earliest survey of anywhere in the world, the Domesday book, Byfleet owed 325 eels a year to their nearest monastery.

GRABER: Japan obviously has a long history with eels — the first written record of a still traditional Japanese dish of filleted and then grilled eel comes from the 1200s.

TWILLEY: And eels were big in the Americas too.

SVENSSON: When the Mayflower arrived in the US in 1620, I think, and the pilgrims were discovering this new, foreign land and they were lost and sick and cold and starving. And they met a man called Tisquantum.

GRABER: Tisquantum, you might have heard of him as Squanto, he was a Native American, and pilgrims wrote home that the very first thing he did was show them how to fish for eels.

SVENSSON: And they loved them. They described them as sweet and fat and the, as a lifesaver actually.

SVENSSON: One year after that they celebrated the first Thanksgiving. And you could argue that instead of turkey, maybe you should be eating eel on Thanksgiving.

TWILLEY: I would gladly make this swap, actually. But for all this very loving human-eel relationship throughout world history, eels have remained something of a dark mysterious stranger. Not for lack of trying.

SVENSSON: Actually started with Aristotle, about 2,300 years ago.

SVENSSON: He wrote a book called the history of the animals. And in this book, he writes a lot about the eel. And most of all, he was trying to explain how eels reproduce.

GRABER: Aristotle obviously knew about sex differences in humans, and he knew you could look for those sex differences in male and female animals, and he really wanted to find sexual organs in eels. But he just couldn’t.

SVENSSON: He came to the conclusion that eels don’t have any.

SVENSSON: He said, they are born out of mud. Life that comes to life from nothing. And that’s a conclusion that actually lived on for, for a long time in almost into modern times.

TWILLEY: Different cultures came up with different stories to explain where on earth eels came from. In Ancient Egypt, people thought eels were born when the sun shone on the Nile in a very particular way.

GRABER: In Italy, people thought that eels came from a special kind of bug that eventually transformed into the eel.

SVENSSON: In, in England they used to think that the eel is born when the hair from a horse falls down into a river, then it’s transformed into a small eel.

TWILLEY: It took practically another 2000 years for science to debunk these many, varied, and super creative eel reproduction myths.

SVENSSON: It wasn’t until the 18th century that, some scientists in Italy actually found an eel with developed sexual organs. A female eel.

SVENSSON: That’s when they started to believe that the eel was actually more like other animals.

GRABER: So a female had been identified. But still, no one had never seen eel testicles, and there were a few scientists searching.

SVENSSON: One of them is actually Sigmund Freud, who in the 1870s, as a young student. He was 19 years at the time and he was studying natural science.

SVENSSON: He took it on himself to solve this eel question that has bothered scientists all the way since Aristotle. And he was actually going to find a male eel with sexual organs. He was going to find an eel testicle, that was his, the big challenge.

TWILLEY: Freud went to Italy, to the port city of Trieste, and he started cutting up eels.

SVENSSON: And he studied over 400 eels during a month. And actually didn’t find one single small eel testicle and had to write a report, confessing that, that he failed.

GRABER: This is kind of amusing if you think about what Freud came to be known for in his later career—

SVENSSON: He was the man who was almost obsessed by the human sexuality. And the man who created a theory about castration complex and penis envy.

SVENSSON: This was the man who actually started his scientific career, trying to explain the sexuality in a fish. Trying to find the male sexual organs in a fish and failed. And you have to at least think that it changed him in some way

GRABER: We have so much to thank the eels for. Really, no comment.

GRABER: But a couple of decades later, Italian scientists did eventually find eel gonads, and they proved that yes, eels do come in male and female, they don’t magically appear out of the mud.

TWILLEY: But testicles were only part of the eel problem. People had also noticed that every autumn some eels headed out to sea and never came back.

SVENSSON: But where did it go? That was the big eel question. Where do the eel go to reproduce and die?

TWILLEY: Again, a lot of people had a lot of theories on this. Italian natural historians thought it all happened in the Mediterranean. Others thought maybe out near the Azores. Where eels had all their sex was a matter of hot debate in the late 1800, early 1900s.

SVENSSON: This is one, maybe my favorite story in the history of the eel science. There’s a Danish marine biologist called Johannes Schmidt, he was gonna find the answer to this question. Where is the eel born?

SVENSSON: And he had a method. He was going out in the ocean with a small boat and catching these eel larva, that is the first stage of the life cycle. Transparent willow leaves.

GRABER: That’s a very evocative name, and these tiny eel larvae are shaped like a little leaf, they’re see-through, and they’re only a few millimeters long. But so looking for them in the ocean was quite a quest to embark on.

TWILLEY: Johannes’ plan was pretty simple — he was going to scoop up all these larvae wherever he found them in the ocean and then measure them. And wherever he found the smallest ones, that would be the place nearest to where they were born.

SVENSSON: And, it was a good method. But the problem is that those small larvas are really very small and transparent. And the Atlantic ocean is very, very big. So.

SVENSSON: He started in 1904, and then he spent seven years sailing around the coast of Europe, catching a lot of eel larva, but they were all kind of big. They were not newly hatched.

SVENSSON: So after seven years in 1911, he understood that he had to go further out in the ocean.

GRABER: Then the first world war broke out, which made things a little challenging for him. But on the upside, he married the heiress to the Carlsberg beer fortune, so that certainly helped. And Johannes just kept going, year after year, on the trail of the baby larvae further and further out into the Atlantic.

SVENSSON: After about 18 years sailing around on the Atlantic ocean catching eel larvas, he came to a place where they were just a few millimeters big.

SVENSSON: And he could finally, you know, conclude that this is the birthplace of the eel. And that was in what we call the Sargasso Sea.

TWILLEY: Both Cynthia and I first came across the Sargasso Sea in a book title — The Wide Sargasso Sea, which is like a feminist post-colonial prequel to Jane Eyre that seemingly everyone read in school. But, even though I’d heard of it, I had no real idea where it was.

GRABER: The Sargasso Sea is actually a big area in the Atlantic ocean that’s to the northeast of the caribbean and to the southeast of Bermuda.

SVENSSON: It’s a strange sea in that it doesn’t have any land borders. The borders are actually the ocean currents, the big ocean currents. And in the middle is the Sargasso sea.

SVENSSON: And it’s very deep and it’s very warm and it’s full of life. And it’s a mythological place in a way too. There, it’s where you find the Bermuda triangle, you know?

TWILLEY: Yes, we promised we’d take you back to this fairytale place. This is where Johannes Schmidt finally ended his quest: at the birthplace of the eel.

SVENSSON: Strange thing about this story is also, of course, that all that this Johannes Schmidt found in the Sargasso Sea were these small, newly hatched larva. He never saw an eel in the Sargasso Sea.

SVENSSON: And still today, a hundred years later. No one has actually ever seen eels reproduce. And no one has even seen a live eel in the Sargasso sea. Only these small larvas. No one has ever seen an eel, not even a dead eel in the Sargasso sea.

SVENSSON: And that’s one of these big remaining mysteries of the eels. They literally disappear into the depths of the Sargasso Sea and they also disappear from human knowledge. In a way.

GRABER: This is completely amazing, and it’s not the only as yet unsolved mystery about eels. We have over the years learned a lot about their astonishing life cycle—like how they turn from a clear leaf-like tiny larva eventually all the way to a long silvery snake-like fish—

SVENSSON: The eel is actually going through metamorphosis, just like, you know, some insects do.

SVENSSON: They actually change. Their bodies change and they become another creature in a way.

TWILLEY: And even while they’re undergoing these incredible metamorphoses, they’re also undertaking an equally astounding journey, starting out as just these millimeters long larvae.

SVENSSON: And they drift with the ocean current all the way from the Sargasso Sea back to Europe. This is like 7,000 kilometers.

SVENSSON: And when they arrive in Europe, they transform into what we call a glass eel. It’s like a very small eel and almost completely transparent.

GRABER: American eels do the same thing but coming to the east coast — European eels and American eels are both born in the Sargasso Sea and literally the only difference between the two is the number of vertebrae, the American eel has fewer. But nobody knows why, and also, nobody knows how the American eels know to peel off for North America and the European eels continue all the way across the Atlantic.

TWILLEY: And then when they reach the coast, no one knows why different eels decide to go up different rivers, for different distances. But once they reach fresh water, they transform again, into what’s called a yellow eel.

SVENSSON: And these yellow eel then in fresh water for 20 or 40 or even 50 years. A very passive solitary life.

SVENSSON: Until it suddenly one fall, it gets this urge to return back to the place it comes from.

GRABER: Nobody knows what triggers the yellow eel to start its trip out to the ocean again, some might only be a few years old and some are decades old. But at that point, it becomes silver.

SVENSSON: The silver eel stops eating. And this is the time when it develops the sexual organs.

TWILLEY: A silver eel can survive up to three years without food, just sort of slowly consuming itself from the inside. And yes, nobody really knows how.

SVENSSON: And they swim all the way back to the Sargasso Sea. Seven thousand kilometers without eating. And then they disappear down in the depths of the Sargasso sea and they reproduce and then they die.

GRABER: But like Patrik’s said, nobody’s seen them reproduce in the Sargasso Sea and nobody’s seen a dead eel there, either. So this is all kind of conjecture. I mean, scientists have tried to pin the eel down—

SVENSSON: There was an American scientist that came up with a plan to, to bring, 100 female eels to the Sargasso Sea and put them in small cages and trying to lure the male eels up to the surface of the ocean, just to get a glimpse of them, you know? But the eel is… the eel doesn’t really cooperate in this, in this kind of work.

SVENSSON: So when, when it got to this, Sargasso Sea with the 100 female eels, 95 of them had already died.

SVENSSON: And they put these five remaining eels in small, small cages and they sunk them down in the ocean, and then they just disappeared.

SVENSSON: All five of them disappeared without a trace and they never saw them again. And that’s, those kinds of things that just seems to happen in the eel science.

TWILLEY: The history of eel science is basically just one story of these slippery eels getting away from humans after another. Patrik told us about another experiment where scientists put transmitters on more than 700 eels and then released them in different spots in Europe to try to follow them back to the Sargasso.

SVENSSON: They didn’t manage to follow one single eel all the way to the Sargasso Sea. They disappeared, they died, or they were eaten by sharks or other animals or their transmitters fell off. And a lot of the eels just mysteriously disappeared.

GRABER: This is all really frustrating for the world of eel science! And it’s not just European and American eels, there are other eel species elsewhere in the world that are equally elusive. Like the Japanese eel.

SVENSSON: When they were trying to find the birthplace of the Japanese eel, they didn’t find it until the 1990s actually. So that’s been even a bigger mystery and the big, bigger eel question then for the European and the American eel.

GRABER: Japanese scientists did eventually find the birthplace of the Japanese eel, it’s in the Pacific Ocean just off the Mariana Islands, to the south of Japan kind of in the middle of the sea there, east of the Philippines, north of Guam. The Mariana Trench is the deepest spot on the ocean floor.

SVENSSON: They actually were able to, to catch three eels at the birth place. They had already been breeding and they were dying. They were very weak and died just some hours after they found them.

SVENSSON: But, but they actually did find them, something they haven’t done with the European eel in the Sargasso Sea.

TWILLEY: Finally, a victory. But really all these centuries, eels have been deeply challenging for scientists.

TWILLEY: On the other hand, from a non-science, purely gastronomic point of view, the eel has consistently been highly rewarding. The Dutch like it smoked and in sandwiches, the Spanish and Portuguese even eat the tiny glass eels using a wooden fork for some reason.

TWILLYE: And in London’s East End, jellied eels and eel pie and mash were the true food of a Cockney geezer.

HARRY CHAMPION: (singing) Oh the fish and the ‘tater shops are grand
So are Cockney saveloys
While a decent meal from a bit of jellied eel
Is one of London’s joys.

GRABER: That’s in England. Patrik said that in his home country of Sweden they had huge eel parties in the fall, where everyone was supposed to eat eels at least four different ways. Smoked, fried, in soup, whatever.

SVENSSON: And you just eat eels for hours and you sing and dance, and then you drink a lot of alcohol.

SVENSSON: And it’s actually recommended that you drink alcohol because you know, the eel is so fat that you need the alcohol to break, to help break it down in your body.

GRABER: This is not medical science, folks.

SVENSSON: From that comes also that the hangover you get from an eel party is probably the worst in the world.

TWILLEY: Although that didn’t apparently stop the Swedes. But especially in the UK and US, these days, people have mostly stopped eating eel. It’s not nearly as common as it once was. So why’s that?

GRABER: That story’s coming up after the break.


TWILLEY: The story of why eels went from being the most commonly consumed fish in a lot of places to today, where a lot of people in the UK and US have never eaten an eel — it’s complicated.

TWILLEY: On the one hand, as railways and my favorite topic refrigeration became widespread, people could eat fresh ocean fish, like salmon, which was seen as much more classy and delicious.

GRABER: And the other problem in North America and in Europe is that we pretty much destroyed eel habitat. Dams in rivers prevented them from migrating and literally killed them, and then we drained marshes, that also destroyed eel homes. Plus we polluted waterways — all of this has been a huge problem for eels.

TWILLEY: The one place where eel eating stayed really, really popular was Japan. The estimate today is that Japanese people eat ten times as much eel as all the other eel-eating countries of the world put together.

GRABER: Most of those eels are yellow eels and they come from big eel tanks. These eels were first caught in the wild in their tiny glass eel form and then raised on eel farms on land.

TWILLEY: People have been farming eels—raising tiny babies into grown adults in ponds—for centuries. Aristocratic Ancient Roman villas sometimes had an eel pond in their garden. Just to supply their endless feasts.

GRABER: The Japanese really perfected the art of raising eels in tanks in the 1970s and 80s — that’s when the Japanese were getting really rich and also they were eating so much eel that their local eel populations were starting to crash.

TWILLEY: Japanese researchers didn’t stop at just figuring out how to farm wild eels — they tried to breed them too. And, amazingly, they did manage to get them to reproduce in captivity.

SVENSSON: That’s never been done with the European or American eel.

SVENSSON: And this of course is a big thing because if you could breed them and grow them in captivity, that will be a big thing financially actually.

GRABER: But like most things we’ve attempted with eels, the fish don’t really cooperate.

SVENSSON: The eel just died in captivity, all the eels born in captivity died. And they wouldn’t eat. And they became misformed.

TWILLEY: So every single eel that is being grilled and served in eel sauce over rice or as sushi — they all start out life as wild caught little baby glass eels. And a lot of them are caught in Maine.

PAT BRYANT: Well, my name is Pat Bryant, and I have been a glass eel fisherman since 1978.

GRABER: Pat fishes for eels in midcoast Maine. And she started back in 1978 because the Chinese had started to build more and more tanks for eels to supply the Japanese market, and they needed baby eels to fill those tanks. They headed to Europe, and also to Maine.

TWILLEY: Pat originally got recruited into the glass eel trade by a glass eel wholesaler who was selling to the Chinese. He was looking for fishermen, and she and her family thought it was worth a try, even they’d never done it before and they weren’t even a fishing family.

BRYANT: So it was just basically trial and error.

BRYANT: And we got, we got a map and we’re looking at all the inlets on the coast and said. You know, “We’ll try here and we’ll try there.”

GRABER: They got some advice from two guys in nearby Yarmouth about what nets to use, and they asked the wholesaler about to look for in the water when they went out searching for baby eels in the spring, when they were migrating in from the ocean—

BRYANT: He just said, “Little, little, tiny, little tiny, they look like little see-through worms with two eyes. You’ll see them.” That’s what we were told.

BRYANT: And then that’s what we did. And… we fished, there was no one else in the state for many, many years. But my family — there was eight of us and all of those were my family, except for the two guys in Yarmouth.

BRYANT: So I actually I had a hairdresser and I owned hair salons and every hairdresser I ever had work for me was also an eel fisherman. And as I said, “this is what we do, guys.” And that’s what we did.

TWILLEY: At the time, this was just a small side hustle — a few nights for a few weeks of the year. The wholesaler paid about five bucks a pound for the baby eels so Pat and her crew made a few thousand dollars doing it each spring.

BRYANT: Of course, at the time that seemed like pretty good secondary income.

GRABER: By the 90s, more fishermen had started getting in on the glass eel business. Sushi was growing more popular in the US, too; the market for eel overall was growing; and there were Chinese fish farmers who were willing to pay.

BRYANT: And the shores were just swarmed with people and it was like, “oh my God.”

BRYANT: The price wasn’t high at that time, but it had gone up to like $25 or something of that sort. But I mean, it was a skinny million people out there at night. And that started, then the state got into it and started to regulate it.

TWILLEY: When Pat started fishing for glass eels in the late 70s and 80s, there were no regulations at all. Then as interest picked up in the fishery, the government put some limits on the overall catch. But things started to get wilder and wilder out there.

GRABER: And by 2010, 2011, the earth shook. Literally. There was an earthquake in Japan and the resulting tsunami, and that wiped out the eels living in Japanese aquaculture systems.

GRABER: At the same time, Europe started to shut down their glass eel fisheries because the eels were disappearing. This meant everyone wanted to buy Maine’s baby eels — the prices for those eels completely skyrocketed. And fishermen got a little nasty.

BRYANT: People would dump your nets, people would steal your nets. People would cut your nets. And we had a thing where I had five nets in one river cut one night — and of course I’d built so many that I just kept replacing them the next day and that really irritated the hell out of them.

TWILLEY: Pat got into wholesaling herself, and she told us she would be driving around with suitcases full of cash. Buyers from China were also showing up on the river banks with suitcases full of cash.

TWILLEY: Millions and millions of baby eels were being taken down to JFK and shipped out to Asia overnight. A pound of glass eels was going for a thousand dollars or more. There was poaching. It all was a little overheated.

GRABER: And so the local government finally got tough on eel fishing. Maine was in a good position to regulate this fishery because fishing was already such a big part of the state’s economy. Even though eels migrate to and live all along the east coast, only Maine has a robust glass eel fishery, there’s also a tiny one in South Carolina.

GRABER: But Maine put in super strong quotas, and everyone has to use swipe cards not cash, and there’s basically no more poaching now.

BRYANT: Well, it’s kind of a good thing they did regulate it because when it got up to like $1000, $1200, that sort of thing, that was unreal.

GRABER: It’s now up to about $2000 a pound.

BRYANT: So even though there’s a lot less eels that we can catch now, you can still make a lot of money. You know, you can make good money.

BRYANT: Like, I just bought my fiance a truck. (laughs) I put in a new house. I have stuff like that I do. Last year, I bought a camper. The year before I bought a boat. You know, it’s that kind of stuff.

BRYANT: You know, you make it so that it, you know, it just gets you the extra stuff beyond the everyday.

TWILLEY: This all sounds great — new boats and campers for Maine fishermen, strong regulations to prevent overfishing. And all Maine’s baby eels ending up on fish farms in Asia. Any issues?

SARA RADEMAKER: Uh… Quite a few.

GRABER: Sara Rademaker is the founder of American Unagi.

RADEMAKER: I mean, first off, you’re, you’re shipping a highly valuable resource out of the state. And, you know, that’s it. There’s no more economic value outside of that, that one sale that’s coming to your state.

RADEMAKER: The other thing is, you know, China is… doesn’t have the best reputation for production and how things are grown and regulations. And there’s been a lot of examples of product coming in that have chemical contamination. So everything from banned animal drugs to just levels of contamination of things that are not supposed to be in our food.

RADEMAKER: The other issue specifically with eel is — you know, eels are all over the world and you don’t know with a product coming from China if it’s, you know, from a well-managed fishery like Maine or from a black-market out of Europe, or an unregulated fishery in, you know, the Caribbean or Africa.

TWILLEY: So Sara decided to change all of that. That story after the break.


GRABER: Growing up in the midwest, Sara loved fish, she had a room full of aquariums. And then she decided to study aquaculture in college in Alabama. And then she moved to Maine.

RADEMAKER: And I started looking around for aquaculture businesses that I could do here. There was oysters. And there was salmon farming in pens. But none of that really was my cup of tea.

RADEMAKER: So I started looking around at different species and saw what was happening with our eel fishery. So, we have this super unique — it is the most valuable fishery per pound and the entirety of the fishery is getting shipped to China to be grown.

RADEMAKER: And to me, I was like, “all right, well, we should just do this here.” Why isn’t anybody doing this?

GRABER: And the answer she found was that nobody really had seen a local market or just really had bothered to try.

TWILLEY: So Sara decided to do it. Starting out in her basement, like all good inventors. She bought some baby glass eels and raised them up to harvest.

RADEMAKER: I literally had like an epiphany over the cutting board after I took the first eels that I had grown. And I had borrowed a smoker from a friend because I had heard eels were great smoked. So I was like, “Oh, you know, I’ll just give that a shot.” And it was incredible.

RADEMAKER: I, you know, smoked these eels, filleted them out and I was by myself in the kitchen and I was just like, “holy…” you know, “I have to make this product.” It’s phenomenal.

GRABER: That was back in 2014. Next Sara partnered with an aquaculture incubator run by the University of Maine.

RADEMAKER: I was working for an algae company at the time and was doing this on the side, just seeing if it would work. So I rented a space, built a little bit larger system, got a few thousand eels and tried that out.

RADEMAKER: And then got some product into the hands of chefs. Because that was the other thing is, I like local fish, but, you know, do people really want a local eel? Do they care?

TWILLEY: And they did. People were calling her, looking for eels.

GRABER: And so last year she expanded again and she started to build the only commercial-sized indoor eel farm in North America.

RADEMAKER: Welcome to the eel farm. (laughs)


RADEMAKER: This is the entrance to the farm. This right here is the grow-out area. So they’re actually building a massive filtration at the end here, but this is going to be finished in the next month.

TWILLEY: We were standing in a big hangar-like space filled with about 40 empty tanks, like oversize hot tubs. Those will be for the growing eels. But for now, the only eels in the farm are little tiny babies, in the nursery next door.

RADEMAKER: So this is where our babies are. There’s a footbath right here.

GRABER: A few weeks ago, Sara bought 650 pounds of baby eels from local fishermen, that means a million and a half tiny little glass eels.

RADEMAKER: Let me grab a flashlight for you.

GRABER: It’s, like, so dense with eels.

GRABER: Look at it, it’s just like full of these tiny little, two-inch-long little wriggly things.


TWILLEY: They’re kind of adorable.

TWILLEY: The babies grow up fast, although as with all things eel, no one knows exactly how old they were to start off with.

RADEMAKER: Up for debate. Again, one of the mysteries of eel. Supposedly, the ones that are coming up from the Sargasso can be maybe as much as a year and a half old. They’ve been drifting on the currents of the ocean before they come into our lovely nursery.

GRABER: The eels are just as wriggly as you’d expect eels to be, and we watched them trying to crawl up the sides of the tank.

RADEMAKER: They can definitely get places. And that’s another part of like, being an eel farmer, you have to make sure there is no holes, no nooks or crannies, because they will find them.

TWILLEY: Sara is constantly finding eels where they shouldn’t be.

RADEMAKER: In filters and pumps where they shouldn’t have gotten. They’ve climbed out of tanks, and it’s never just one. They like, tell their friends. They’re like, “This way, guys!” Like “Hey, I found a weakness in the wall. Let’s go!”

TWILLEY: There were about one hundred and twenty-five thousand little wriggly glass eels in each tank. Which you might think oh no, poor things, they are all crammed in and they have no personal space. But apparently eels like it like that.

RADEMAKER: That’s one of the good things with eels is that they actually like to be in very high densities. So if you look around, even when they’re relaxing, they’re lying around in piles. They like — they’re tactile. They don’t want to be at low densities. They actually don’t do well. So that allows us to farm in a much smaller footprint than other fish.

GRABER: Eels like cuddle puddles! Later Sara told us that’s just one of their strange and yet endearing behaviors.

RADEMAKER: Like they’ll sometimes, you know, lay on their back upside down. And I’ve never worked with a fish like that. You literally walk in, you’re like, “oh, there’s a dead one.” And you walk up and then it just rolls over and swims off. Like it’s just relaxing on its back. Like, that’s bizarre.

RADEMAKER: And you know, just things like that, behaviors, they’re curious. Like if you change something in the tank, they’ll go and check it out. They come out of the water and will like poke things, which also is very unusual for any fish that I’ve worked with. So. Yeah, little things like that, that we’ve, are very entertained by our fish.

GRABER: Sara’s design for her farm is based on eel farms in Europe, she even had some Dutch fish farm engineers building things out when we visited. But she’s made a few tweaks of her own to improve the system — of course, those are her secret sauce, so she couldn’t share them with us.

TWILLEY: Some of what Sara’s done is just try to look at how eels live in the wild and copy it. But one thing that is very different from life outside in a Maine river or lake is that Sara keeps the water at a lovely warm consistent temperature round about 70 to 75 degrees.

TWILLEY: That means that the eels grow faster — in the wild, when the water gets down to 50 degrees or below, eels stop eating and just kind of hang out in the murky bottom waiting for spring.

GRABER: In the wild, eels take between five and thirty years to reach a decent size, but American Unagi eels eat all year round, and so they reach a harvestable size between only seven months and two years.

TWILLEY: There’s an art to knowing when an eel is ready to be harvested. Sara runs her hands over each eel to see whether they’re plump and tender enough.

RADEMAKER: You can also tell by looking at them like if they’re, if they’re fat enough, they, you know, get little rolls and their, you know, their faces look small because their bodies are so plump.

RADEMAKER: And they turn their heads, they look like they have little rolls. Like that’s when you know your, your eel’s ripe.

GRABER: Sara buys all of her glass eels from fishermen in Maine. This year, the run was so strong that the fishermen maxed out their quota in just two weeks instead of the usual more than a month.

TWILLEY: But the baby eels were still running. They were still heading up the Pemaquid river to wherever they wanted to live and grow up. So we went out to see them with one of the fishermen Sara works with, John Taylor.

TAYLOR: Well, yeah, right. This is my office. And… come on. (laughs) it’s a beautiful river. What more can you ask for, you know? You usually get good company to hang out with, go fishing.

GRABER: It was a calm evening, a little drizzly out, and the sun was just starting to set. The eels don’t really come out until night falls. And John knows where to find them.

TAYLOR: You just got to kind of know where they are. That’s all. So usually what happens is they come in from the ocean. They’ll start to run into this current. And the current forces them to the side because they’re just little fish, you know?

TAYLOR: So you just set your net in front of them. They swim in it. You empty it out.

TAYLOR: It is one of the easiest fisheries as far as you don’t have to gas up a boat, you don’t have to bait a trap. They swim in it. So it’s really just about where you position your net.
TWILLEY: When we arrived, it seemed pretty dark to me — certainly there was no sun, but the eels were a little sparse at first.

TAYLOR: So you guys kind of showed up a little early. Oh- there’s one right there.

TWILLEY: Oh! There’s one!

TAYLOR: Yeah, there they go, there’s one.

GRABER: Oh, yeah.

TWILLEY: There he is! Heeyyy.

GRABER: John had the idea to walk a little further up river to a rocky area he was pretty sure the eels were going to love. And as we trudged over there through the mud, it got even darker out…



TAYLOR: So they’re right in the grass. You can see ’em–they’re right there. There’s a whole bunch of them right there.


GRABER: Oh, yeah. Look at that!

TWILLEY: Wait, where?

GRABER: See look, there’s a whole group of them. Right over there!

TWILLEY: Oh! Hahaha!

GRABER: Oh my gosh. There’s just more and more. Look at that.

TAYLOR: They’re showing up here now. This is getting good.


TAYLOR: A little tiny fish. You wouldn’t even know what was happening because it all happens at dark. Nobody ever sees this. You know.

TWILLEY: The stream of baby eels really picked up — they looked like this long strand of blueish threads in the water — kind of like curls of smoke, and the thread stretched back as far as the flashlight reached, thousands and thousands of them, all trying to get up river.

GRABER: A couple of weeks earlier, when John set his nets, the shores were lined with other fishermen doing the same thing.

TAYLOR: You get a lot of competition. You know, there’s 425 fishermen, plus 800 Native Americans in a little stream.

TAYLOR: Pretty much just line ’em right up. Really no spaces left once everybody sets in, so… But they’ve got us regulated pretty good, so it works out. Even on a bad year it seems to work out. Everybody seems to do all right.

TWILLEY: This year was a good year, and John sold a bunch of his baby eel catch to Sara. With the new farm, Sara buys something like eight percent of Maine’s total glass eel catch. And she turns that into a half a million pounds of eel.

GRABER: But that’s only a sliver of the total American eel market. 95 percent of eels eaten in America will be grown overseas, most likely in China, even if they were fished in Maine. And Sara wants to change that.

RADEMAKER: Yeah, I think there’s an opportunity to, to build more of these in the community and throughout Maine. So, you know, you could build 15, 20 more of these facilities and that would just support the existing fishery.

TWILLEY: Sara processes her eels on site — there wasn’t really anyone who wanted to handle her eels for her when she started out, so she teamed up with some locals and figured it out.

GRABER: She sells live eels and frozen fillets to restaurants, and she also smokes the eel in house, you can buy smoked eel on her website, and then there’s a company called Gulf of Maine Conservas who also cans her smoked eel.

RADEMAKER: So my boyfriend actually, he has a smoking barbecue business here in town. So he helped me develop, initially, all of the smoking recipes. So we use oak and alder. It’s a short, hot smoke and eel is super-rich, so it absorbs smokiness really well.

TWILLEY: Obviously our mouths were watering at this point. So we sat down amidst all the construction and tried some American Unagi eel.

RADEMAKER: So we’re going to start first with the, um, just the plain smoked eel and then we’ll do the canned after that.

TWILEY: Okay. Alright, let’s do this.

GRABER: Okay, here we go.



GRABER: It’s so rich.

TWILLEY: The smoke is perfect.


TWILLEY: It’s very melty.

GRABER: We first tried the smoked eel plain, it’s rich and buttery and has a delicate flavor, it wasn’t super fishy tasting.

TWILLEY: And then we moved onto the canned smoked eel. And Sara added her secret ingredient.

RADEMAKER: Apple cider vinegar. This is wild.


RADEMAKER: Okay. I’m gonna have to make sure I added enough. Let me test it before I hand it off to you guys.

GRABER: Okay. Oh, wow.

TWILLEY: That’s amazing.

GRABER: That’s so good. Mmmmmmm. That’s amazing.

Sara Rademaker: Doesn’t it taste like pork, or like Carolina barbecue?

GRABER: It kind of did! We polished off the entire can and the package of smoked eel, too. I was quite full.

TWILLEY: Very full and very happy. But we did have a concern. The American eel is officially listed as endangered, so I felt kind of weird eating it.

GRABER: I did, too. I’d never eaten eel at all before, ever, because I’d been so concerned about the sustainability issues. I was feeling a little better knowing how tightly Maine regulates the quota, but there was one thing Sara said that really made me feel like American farmed eel was the only eel I’d ever feel comfortable eating.

RADEMAKER: When you look at our use of a wild fish our survival on the farm is over 90%.

RADEMAKER: You know, when these fish are in the wild, these glass eels, it’s something like maybe 1% reach adulthood or market size. So, you know, we’re taking a very small portion of, of the wild and then really being able to produce a lot more than what would have survived in the wild.

TWILLEY: So not only is Sara’s eel totally traceable back to a really tightly regulated fishery, it’s also making the absolute most of a wild resource — more than you’d get from leaving it in the wild. Sara likes to say it’s a better eel.

GRABER: And for me at least still just an occasional treat, turns out that eel is really appropriately quite expensive.

TWILLEY: Yeah I was about to order a case of those tins of smoked eel until I saw the price.

GRABER: But eels are still endangered around the US and Sara’s trying to help with that, too. She loaned some eels to researchers working on a design for a fish-safe turbine for dams, so eels don’t get chopped up as they try to go upstream.

TWILLEY: And she’s hooked up scientists at the University of Maine with DNA samples from her water system so they can come up with accurate methods to sample Maine river water and figure out the state’s population of wild eels.

GRABER: An accurate population number is just another one of the many mysteries of the eel. Honestly, for such a delicious and important food, Patrik says it’s kind of amazing that there are still so many mysteries.

SVENSSON: You could, of course, argue that there’s a lot of animals that we know less about than we know about eels. And there’s a lot of animals that we don’t know about at all in the ocean deep, of course.

SVENSSON: But when you look at all the efforts that natural science has put into the eels for such a long time, all the way since Aristotle. And all these very prominent scientists, trying to understand the eel.

SVENSSON: And, and when you look at all the things we still don’t really know about it after all this, then I will say it’s absolutely one of the world’s most mysterious animals.

TWILLEY: We may need to solve some of those mysteries to save the eel — but for now, they are a huge part of what makes it such a magical fish.

SVENSSON: People have often asked me also, do you want all these questions to be answered? And, I’m not sure. You know.

SVENSSON: For example, just if they would find an eel in the Sargasso Sea, that would be a big thing. Of course. That would be one of the mysteries remaining to find an eel in the Sargasso Sea.

SVENSSON: And when that happens, if that happens, of course, I would be, excited in a way.

SVENSSON: But also of course, a little bit disappointed. (laughs)


TWILLEY: Thanks this episode to Patrik Svensson, his book is a delight and you should read it, links on our website at gastropod dot com.

GRABER: Thanks also to Sara Rademaker and all her colleagues at American Unagi who met us when we were there — Eater also has a cool video about their eel farm, and you can find it on our website.

TWILLEY: And finally a huge thanks to John Taylor and Pat Bryant and our superstar producer Claudia Geib. We’ll be back in your feeds soon!