In the spring of 2019, a small research team stood on a boat near the middle of the largest lake in Alaska, feeding a cable over the side, lowering a camera into water so deep and so dark that no light from the surface had ever reached the bottom of it.
They were aiming for the deepest spots they could find, >> >> somewhere down around a thousand feet.
The camera went down through the cold, and the cable kept paying out.
And on a screen on the boat, the picture stayed the same, which is to say, it stayed black with the occasional particle drifting up through the beam of the light they’d sent down with it.
They had another tool, too, which didn’t look like anything.
Bottles.
They were taking water from different depths and different parts of the lake to sift for DNA, for the traces that every living thing sheds into the water around it, the loose cells and the broken strands, which a laboratory can read like a guest list.
And the thing they were looking for, the reason the camera was going down into the dark of a lake in the Alaskan bush, was an animal that people who live on that lake have been describing for 80 years.
Something long, something dark, something that comes up and goes down, and that nobody from the outside has ever been able to name.
I’m not going to tell you yet what the camera found, or what the water said, because the answer, when it came, came from a direction nobody was pointing, and it’s stranger than the monster.
And I want you to arrive at it the way the science did, slowly, from the side, while looking at something else.
I And then I read about the seals, and I changed my mind.
Because it turns out there is a genuine mystery in that lake, a real one, with real evidence that scientists are still untangling right now, in the last two years.
And it has nothing to do with a monster.
And at the same time, it has everything to do with it.
So, let me do it properly.
Let me start with the lake.
Iliamna Lake is in Southwest Alaska, on the Alaska Peninsula, the long arm of land that reaches out toward the Aleutians, about 200 miles from Anchorage and a world away from anything.
It’s enormous, about a thousand square miles of surface, 75 miles long, the largest lake in Alaska and one of the largest in the United States, bigger than some states worth of water.
And it sits in a bowl of mountains and tundra with a scatter of tiny villages around its edge, places like Iliamna and and Kokhonak and Pedro Bay.
Most of them with populations you could count in the dozens.
Most of them reachable only by small plane or boat.
And it’s deep, over 900 feet at its deepest by the published figures, which puts a lot of very cold, very dark, very old water a long way below the surface.
The eastern end is the deep end, up against the mountains, full of islands and inlets and tributary mouths, the kind of complicated, folded shoreline where a big lake keeps its secrets.
Here’s the thing about Iliamna that matters most and that almost no monster video bothers to mention.
It’s connected to the sea.
Out of the western end of the lake runs a river called the Kvichak and the Kvichak runs about 70 miles down to Bristol Bay, which opens onto the North Pacific.
And that river is one of the great salmon roads of the planet.
Iliamna Lake is the nursery for the largest run of sockeye salmon on Earth.
Tens of millions of fish come up the Kvichak every summer, through the lake to spawn in its tributaries.
And the whole ecosystem, the bears and the eagles and the people, is built on that run.
Hold on to the salmon.
And hold on to the fact that the lake has a door to the ocean, 70 miles long, because both of those things are going to matter.
And the salmon are why anyone from the outside is there at all.
Iliamna is the beating heart of the Bristol Bay fishery, which is worth hundreds of millions of dollars a year and feeds a huge share of the world’s wild sockeye.
And it’s the reason there have been for years fierce fights over a proposed copper and gold mine, the Pebble mine, at the headwaters of the watershed.
So, this isn’t some forgotten pond.
It’s one of the most economically and ecologically important lakes in North America, studied by fisheries scientists every single summer with millions of fish counted through it.
Which makes the central fact of this whole story even stranger.
A lake that careful people have been counting salmon on for a century, and the most remarkable animal in it was barely studied until the 2020s.
Now, the monster.
The stories are old, older than the float planes.
The Yup’ik and Dena’ina people who have lived on that lake for thousands of years have accounts of a large and dangerous creature in the water, a thing that could take a man or a boat.
And those accounts are theirs, and they predate every outsider who ever flew over the lake with a notebook.
I’m going to be careful here because it’s easy to flatten a lot of different communities knowledge into one cartoon legend, and I don’t want to do that.
What I’ll say is that the idea of something big and dangerous in Iliamna did not start with a magazine.
It was there a long time before.
I think the indigenous accounts and the float plane accounts are two different kinds of knowing, and it’s worth keeping them apart.
The old stories are about a being, a presence in the water with meaning and danger attached, and they belong to the people who hold them and shouldn’t be flattened into a cryptid headline.
The pilot sightings are something else, a modern outsider empirical thing.
A person going, “I saw a shape, and I don’t know what it was.
” When this story gets told badly, the two get mashed together.
The ancient tradition used as a kind of authenticity stamp on the monster hunt.
I’d rather hold them separately.
One is a culture’s relationship with its lake.
The other is a puzzle about what a pilot’s eye can and can’t resolve through moving water.
The outside world got hold of it in the middle of the 20th century, and the way it got hold of it is the float plane.
Because the only practical way to cross that country is a small plane on floats, flying low.
And when you fly low over clear water in good light, you can see down into it.
And in the 1940s, bush pilots started reporting that they were seeing things in Iliamna.
Long things.
Pale, some of them said.
Silvery.
Aluminum-colored, like the belly of a plane.
Like a submarine.
15, 20, 25 ft long.
Moving under the surface, and then gone.
And once a few pilots had said it, more of them said it, and the sightings started to stack up, decade after decade.
And they’re worth going through because the pattern in them is the actual story.
In 1958, by the account that got printed in a hunting and fishing magazine the next year, a party went out on the lake to try to catch the thing.
Big game.
The biggest.
They baited with meat and ran it on a heavy line, stainless steel cable.
And the story goes that something took it, and the cable snapped.
A 1/16 of an inch of steel cable, broken.
Now, I want to flag that hard because it’s the kind of detail that sounds like evidence and isn’t quite.
We don’t have the cable.
We don’t have an independent examination of it.
We have a magazine writer’s account of a fishing trip, and a broken line can be broken by a lot of things.
A snag, a flaw, a big ordinary fish, and it tells you nothing about the size or the nature of whatever pulled it.
But, it’s where the modern legend really starts.
With a snapped cable and a story.
The next year, 1959, somebody went looking properly, or as properly as you could then.
A wealthy adventurer and cryptid hunter named Tom Slick, the same man who’d funded expeditions after the Yeti and Bigfoot, hired a local bush pilot, a legendary one named Babe Ellsworth, to search the lake from the air.
And they looked, and by the accounts that survive, they found nothing.
That’s the first time the pattern shows up, the one that’s going to repeat for 60 years.
Somebody mounts a search, the search comes back empty.
Then, the sightings keep coming.
1963, a report of a biologist who supposedly watched a fish 25-30 ft long from the air for 10 minutes and said it never came up for air.
I have to flag that one, too, because the biologist is unnamed, and an unnamed expert in a retelling is a weak link, however good the story sounds.
1967, a missionary who saw something and a friend who tried to catch it with hooks rigged to a floatplane, and a story about the plane being jerked and the man ending up in the water and the cables gone.
1977, a pilot named Tim Laporte flying near Pedro Bay, who described a fish-like animal with an arched back that made a big splash and moved off with a sideways sweep of its tail.
1987 and 1988, reports of a large dark animal, black with a pale stripe along its fin near the surface.
And then the ones that I think actually point somewhere.
1996, a bush pilot named Bo Bennett, who said he saw not one animal, but 10 or 12 dark shapes in the water and circled and watched two of them, about the size of sea lions, swim near the surface and disappear.
2008, an anthropologist named Robin Levine flying low, who saw a grayish animal maybe 15 ft long with a long head and a prominent tail and side fins moving in a way that stirred up the sandy bottom.
And 2017, near the village of Kokhanok, a man named Gary Niolson and other residents who described three animals surfacing about a mile offshore.
The largest of which Niolson put at around 70 ft, with smaller ones following, surfacing and appearing to blow water.
70 ft is worth one more sentence on how badly people judge size over water, because it’s the hinge the whole legend swings on.
With nothing floating beside an animal to give you scale, your brain guesses and it guesses using distance.
And over clear water, you misjudge distance badly and the errors don’t cancel, they compound.
Experienced observers have confidently called 6-ft animals 20 ft and 20-ft logs 60.
A 70-ft estimate across a mile of lake from a boat is not a measurement of an animal.
It’s a measurement of how hard that measurement is.
70 ft.
Hold that one lightly.
A length estimated by eye across a mile of water with nothing next to it to measure against is not a measurement.
It’s an impression.
And impressions of size over water are notoriously wildly unreliable.
But hold the rest of the 2017 account because there are three details in it that are about to become the whole story.
Three animals in a group surfacing and blowing.
The sideways moving tail is the detail I keep coming back to.
A fish moves its tail side to side.
A whale or a seal or any marine mammal moves it or its whole hindquarters up and down.
The 1977 pilot described a sideways moving tail which sounds like a fish and that’s the detail the monster people lean on because it argues against a mammal.
But a seal underwater doesn’t swim like a seal on a beach.
It sculls with its hind flippers and undulates its body.
And from above at speed through the lens of a bending surface, which way a dark shape is flexing is exactly the kind of thing the eye gets wrong.
I’m not telling you every witness saw a seal.
I’m telling you that the one detail that’s supposed to rule a seal out is the single least reliable thing a person can judge from a floatplane.
Because now I need to tell you about the seals.
Iliamna Lake has seals in it.
Freshwater seals.
Harbor seals.
The same species you’d see hauled out on a rock off the coast of Maine or California or Scotland, living permanently, year-round, generation after generation in a freshwater lake 70 miles and a long river from the sea.
And this is not a legend, and it’s not a sighting, and it’s not a tall tale.
It’s a documented, counted, studied fact.
There are, depending on the year and the survey, something like three or 400 of them in the lake.
The state of Alaska lists them.
They’re one of only a handful of freshwater seal populations on Earth, maybe five in the whole Northern Hemisphere, alongside places like Lake Baikal in Siberia and a couple of lakes in Russia and Canada.
And they are, by a wide margin, the least studied of them.
And they are genuinely rare globally as a phenomenon.
Seals are ocean animals.
For a population to live full-time in freshwater is a strange and special thing, and there are only a handful of places on Earth where it has happened.
The most famous is Lake Baikal in Siberia, which has the nerpa, the world’s only truly freshwater seal species isolated more than a thousand miles from any ocean.
There’s the ringed seal of Lake Ladoga and the Saimaa seal in Finland, each its own isolated remnant.
A couple of populations in Canada.
And Iliamna.
That’s close to the whole list.
The Iliamna seals are, in that company, the least known of all of them, the ones the science got to last, which is astonishing when you remember they live in the United States, in a lake with a fisheries program on it, not in the remote interior of Siberia.
Think about what a harbor seal is, and then think about the sightings.
A harbor seal is a large, dark, sleek, air-breathing animal.
An adult is 5 or 6 ft long.
They’re gray to black, some with pale patterns.
They surface to breathe with a little puff of exhaled air, and they dive and vanish.
They move in the water with a sideways motion.
They gather in groups.
They haul out and slip back.
From a floatplane, low over clear water, at speed, with the light bending on the surface, a seal or a cluster of seals is exactly the kind of thing that a person who did not know there were seals in that lake would struggle to name.
A dark shape surfacing, blowing, in a group, 15 ft if you’re bad at judging length over water, which everyone is.
The 2017 Kokanee sighting, three animals in a group surfacing and blowing a mile offshore, is to my eye a description of seals by people describing what they genuinely saw.
Bo Bennett’s 10 or 12 dark shapes the size of sea lions in 1996 is a description of seals.
The pale stripe, the dark back, the side fins, the sideways tail, over and over through the decades, people were describing, I think, a real animal that really lives in that lake and that for most of the 20th century the outside world flatly did not know was there.
And here’s the part that gets me.
And here’s why I changed my mind about doing this video.
The seals aren’t the debunk.
The seals are the mystery.
Because in the last few years scientists have finally started to study them.
And what they found is stranger than a monster.
In 2019 the same year that team lowered the camera into the dark looking for Ili, other researchers were doing the quieter work, collecting samples, including, cleverly, seal scat, which let them get genetic material from far more animals than they could ever have caught.
And in October of 2024 a team led out of Florida Atlantic University with NOAA and the University of Washington and others published what they found in a journal called Biology Letters.
The Iliamna seals are genetically distinct.
Not slightly.
They differ at multiple genetic markers from every other harbor seal population in the Pacific, a range that runs all the way from Japan to California.
They show lower genetic variation and signs of inbreeding, the fingerprints of a small population cut off from the rest of its kind for a very long time.
The researchers used words that scientists choose carefully, evolutionarily, reproductively, and demographically discreet.
A separate population that receives, in one author’s words, no or very few immigrants.
And they raised the possibility, cautiously, that these animals might be a unique endemic form of harbor seal, possibly a subspecies of their own.
An animal found in that lake and nowhere else on the planet.
And the method that cracked it is worth a word, because it’s clever and it’s humane.
You can’t easily catch and sample three or 400 wild seals in a giant lake.
So, the researchers used what the seals left behind, scat, seal droppings, collected from the haul-out rocks full of the animals’ own shed cells, readable for DNA.
It let them sample far more individuals than they could ever have netted, quadrupled their numbers without laying a hand on an animal.
The great genetic revelation about one of the rarest mammal populations in North America was built, in large part, out of what the seals left on the rocks.
How long have they been there? Indigenous knowledge and the accounts of the early Russian explorers, the scientists say, suggest the seals have been in Iliamna Lake for at least 200 years.
At least.
The genetics suggest isolation deep enough that it could be a great deal longer.
A colony of seals sealed into a lake in the Alaska bush, breeding only with each other, drifting away from their ocean cousins for centuries, possibly for millennia, becoming something slightly, measurably, their own.
That’s the thing in the lake.
Not a plesiosaur, not a monster fish 70 ft long, a population of seals that may be found nowhere else on Earth that science has only just confirmed is unique in a lake that the outside world spent 80 years flying over looking for something that wasn’t there, while the actually remarkable thing was hauled out on the rocks the whole time.
Once you see that, you can’t unsee it.
You go back through the sightings and the dark shapes and the surfacing and the blowing and the groups stop looking like evidence of a cryptid and start looking like the first fumbled outsiders descriptions of an animal that the people who live on the lake had known about forever.
The monster hunters were looking down from their planes and seen something real and misreading it because they didn’t have the one piece of information that would have told them what it was.
Let me lay it out.
A lake the size of a small state in the Alaska bush connected to the sea by a 70-mi river that carries the biggest sockeye run on Earth.
Stories of a large dangerous creature, old, indigenous, predating every outsider.
Floatplane [snorts] pilots from the 1940s on seeing long dark shapes, naming them submarines and monsters.
A snapped cable in 1958.
An empty aerial search in 1959.
Decades of sightings, each one a dark animal surfacing and diving, sometimes in groups.
A camera lowered 1,000 ft into the dark in 2019 looking for Illy.
And in those same years, in the quiet, a colony of several hundred freshwater seals was turning out to be genetically unique, possibly their own subspecies, isolated in that lake for centuries, confirmed in a journal in 2024.
That’s the shape of it.
The monster everyone searched for was never found.
The animal nobody from outside was looking for turned out to be one of the rarest strangest populations of mammals in North America.
And it was never hidden.
It was just never asked about.
So, let me come back to the camera and 2019 and what it actually found because I promised I’d tell you.
The honest answer is not much and that’s important and I’m going to be straight about it the way I always try to be.
The 2019 effort led by a camera specialist named Charlotte Levy and her colleagues was real.
They lowered a camera toward the deepest water, around 1,000 ft, and they sampled the lake for DNA.
And the sources I can actually verify do not show that the camera captured a previously unknown creature, and do not show a DNA result that identified a mysterious giant animal.
What they captured, as far as the public record goes, was dark water and the ordinary business of a lake.
The DNA, sifted properly, would mostly return exactly what you’d expect from Iliamna, salmon, trout, the other fish, and somewhere in it, seal.
The title of this video promises that what the drone captured was unexpected, and I want to be careful with you about that, because the unexpected thing isn’t a frame of monster footage, it’s the inversion of the whole search.
They went down looking for a creature nobody could name, and the real answer was already swimming at the surface, already counted by the state, and in the 5 years after that dive, it got stranger.
Not because the camera found it, but because the geneticist did.
The unexpected thing the investigation of Iliamna turned up is that the lake really does contain an animal science didn’t fully understand.
It’s just that the animal breathes air and suns itself on rocks, and the people of Kokhanok and Pedro Bay could have pointed to it from shore.
There’s one more camera story, and it’s the one that keeps the mystery, honestly, alive.
So, I’ll give it to you with its weaknesses attached.
In 2020, by an account published by a Bristol Bay fishing group, a baited underwater camera rig was set in the lake, hooked up with sockeye salmon to draw something in.
And the account says that something large damaged the rig.
And the account also says, in the same breath, that the camera’s battery had died shortly before it happened.
So, the one moment that might have shown you something is the one moment there’s no footage of.
Now, in a monster video, that’s where the narrator’s voice drops and the music swells, and you’re told the truth was almost caught.
I’m not going to do that.
A dead battery and a damaged rig is a story, not evidence.
Maybe a seal went for the salmon.
Maybe a big lake trout, and Iliamna grows them large.
Maybe a bear in the shallows.
The missing footage isn’t proof of anything except that cameras run out of power at the worst possible moment, which anyone who’s ever filmed anything already knew.
But it’s real, and it’s unresolved, and I’d rather hand you the real unresolved thing than a fake resolved one.
So, here’s the official position, and this is a case where I think the official position is not only right, but more interesting than the legend.
The scientific view is that Iliamna Lake contains a documented resident population of freshwater harbor seals numbering in the low hundreds, that this population is genetically distinct from all other Pacific harbor seals, and may represent a unique endemic form, and that it has been isolated in the lake for at least two centuries, and likely far longer.
The view is that the lake is enormous, deep, cold, remote, and difficult to survey, that it supports large fish including lake trout, and seasonally immense numbers of salmon, and that the long history of monster sightings is most plausibly explained by a combination of these real animals, seals especially, seen under the difficult conditions of low altitude flight over bending water, where size and shape are easy to misjudge.
The view is that no physical evidence, no body, no bone, no unambiguous footage has ever established the existence of an unknown large creature in the lake.
And the view is, finally, that this does not make Iliamna boring, because the thing that is actually in there is genuinely rare and genuinely new to science.
I believe all of that, and I want to tell you where the honest open edges are, because there are some.
Not every sighting is a seal.
A five- or six-foot seal explains a dark shape blowing at the surface in a group.
It does not obviously explain the handful of accounts of a single animal 25 or 30 ft long.
Those are either misjudged size, which is the most likely answer, and which human beings do constantly over water, or large fish, or exaggeration that grew in the retelling, or something not yet accounted for.
The lake has never been systematically surveyed below the surface.
Not really.
Not all 900 ft of it across 1,000 square miles.
A camera in one deep hole is not a survey.
So, the scientifically honest statement is not there is definitely nothing else.
It’s there is no evidence of anything else.
There is a rare, real thing instead, and most of the lake has never been looked at.
That’s a more interesting place to stand than certainty in either direction.
And there’s a silence in this story, and it’s the one I keep circling back to.
Because it isn’t the silence these videos usually claim.
The usual move in this genre is the cover-up.
The missing footage, the search that was called off, the expert who went quiet, all reframed as suppression, as evidence that somebody doesn’t want you to know.
And there’s none of that here.
Nobody suppressed the seals.
The Alaska Department of Fish and Game has a public page on them.
The genetic study is published and free to read.
The 2019 search was covered by the Associated Press.
The real silence is older and quieter, and I think sadder.
It’s that the people who live on Iliamna Lake knew about the seals the entire time.
The Yup’ik and Dena’ina communities around that water have known those animals for generations, hunted them, named them, understood them as part of the lake for the 200 years the Russian accounts confirm, and almost certainly much longer.
The knowledge was never missing.
It was just never asked for.
The outside world flew over the top of it for 80 years, chasing a monster, writing magazine articles, funding aerial searches, lowering cameras.
And the answer was sitting with the people on the shore the whole time, in a body of knowledge that the floatplane crowd never thought to consult.
The scientists who finally cracked the seal mystery say it plainly in their own paper.
Indigenous knowledge is one of the two sources that told them the seals had been there 200 years.
The discovery was the outside catching up to what the inside already knew.
That’s the silence at Iliamna.
Not a conspiracy.
A failure to listen that lasted the better part of a century to the people who had the answer.
So, the questions I’m left with, because I’m left with real ones, and that’s rare for a subject like this.
How did the seals get there, and when? Did they come up the Kvichak River from Bristol Bay chasing salmon generations ago and simply stay and lose the way back? Did they get trapped when the geography changed after the last ice age, which would make them not 200 years isolated, but 10,000? The genetics point deep.
Nobody yet knows the bottom of it.
How do they survive the winter? Iliamna freezes.
A harbor seal is an air-breathing mammal under a lid of ice for months.
Do they keep breathing holes open the way Arctic seals do? Do they use the places where the current keeps the ice thin? The least-studied freshwater seals on Earth, and this basic thing about their lives is barely documented.
Are they a subspecies? The 2024 paper raised it and didn’t settle it.
If they are, they’re an endemic mammal found in one lake and nowhere else in the world, and that’s a conservation question with real stakes, because there have been proposals over the years for a massive mine in that watershed.
And what you owe a unique animal is different from what you owe a stray one.
What’s in the deep water? >> >> 900 ft, cold and dark and never surveyed.
Probably nothing, but very large, very old lake trout.
Probably.
But a camera has been down one hole of it once.
And the honest answer to what lives in the deep middle of Iliamna is that we have barely looked.
What did the Russians see? The genetic paper leans partly on early Russian explorers’ accounts to date the seals to at least 200 years ago.
Those accounts are sitting in archives.
What exactly did they describe? And did the Russians, arriving by sea and knowing perfectly well what a seal was, simply write down seals in a lake as a curiosity, while two centuries later outsiders flying over the same animals called them monsters? If so, the people with the clearest eyes on this were the first ones there.
And the one I keep ending on.
How many other answers are sitting on how many other shores with the people who’ve always lived there, while the rest of us fly over the top looking for something more exciting than the truth? I want to end on the ICE.
It’s the middle of the Alaska winter, and Iliamna Lake is frozen.
A thousand square miles of white, with the mountains black behind it, and the villages strung around the edge with their wood smoke going straight up in the cold.
And somewhere under that ice, in the dark, in water just above freezing, there are several hundred seals breathing.
Diving for fish in water with no light in it, surfacing at the holes they keep open.
A dark head in a circle of black water in a field of white.
And then, gone again, under for the winter, the way their parents did, and their parents, back and back, 200 years, maybe 10,000, in a lake their ancestors swam into and never left, becoming, slowly, by the arithmetic of isolation, an animal that exists in that one place and nowhere else.
That’s what was in the lake.
Not a monster.
Something rarer.
A creature that found a door to a hidden world, went through it, and stayed so long it turned into itself.
The camera went down a thousand feet looking for a legend.
The answer was at the surface in the sun the whole time.
If you’ve lived on Iliamna or flown over it or seen something in that water you couldn’t name, I want to hear it in the comments.
And I especially want to hear from anyone whose family has known those seals longer than the science has.
And if you know of another place where the people on the shore had the answer all along while the rest of the world went looking, tell me.
That’s where the next one of these usually comes from.
I have a feeling this isn’t the last time we go down.
I’ll see you in the next one.
