Category Archives: sea monsters

Episode 075: Archelon and Other Giant Sea Turtles

This week we’re going to find out about the biggest turtles that ever lived! Spoiler: one of them is alive right now, swimming around eating jellyfish.

A green sea turtle. These guys are adorable:

A hawkbill glowing like a neon sign!

The majestic and enormous leatherback:

Bebe leatherback. LET ME GOW

Seriously, how are baby sea turtles so darn cute?

Archelon was a big tortle:

Further reading:

This is a link to a pdf of that “Historicity of Sea Turtles Misidentified as Sea Monsters” article

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re back in the sea, but not the deep sea this time, because we’re looking at marine turtles!

The oldest known turtle ancestor lived around 220 million years ago, but it wouldn’t have looked a whole lot like a modern turtle. For one thing, it had teeth instead of a bill. It resembled a lizard with wide ribs that protected its belly. It lived in the ocean, probably in shallow inlets and bays, but it may have also spent part of its time on land. Some researchers think it may have had at least a partial shell formed from extensions of its backbone, but that this didn’t fossilize in the three specimens we have.

The oldest sea turtle fossil found so far has been dated to 120 million years old. It was seven feet long, or 2 meters, and already showed a lot of the adaptations that modern sea turtles have. Researchers think it was closely related to the green sea turtle and the hawksbill sea turtle.

Seven species of sea turtle are alive today. They all have streamlined shells and flippers instead of feet. They all breathe air, but they have big lungs and can stay underwater for a long time, up to about an hour while hunting, several hours when asleep or resting. Like whales, they surface and empty their lungs, then take one huge breath. They can see well underwater but can probably only hear low-frequency sounds.

Sea turtles have a special tear gland that produces tears with high salt concentration, to release excess salt from the body that comes from swallowing sea water. They migrate long distances to lay eggs, thousands of miles for some species and populations, and usually return to the same beach where they were hatched. Female sea turtles come ashore to lay their eggs in sand, but the males of most species never come ashore. The exception is the green sea turtle, which sometimes comes ashore just to bask in the sun. Once the babies hatch, they head to the sea and take off, swimming far past the continental shelf where there are fewer predators. They live around rafts of floating seaweed call sargassum, which protects them and attracts the tiny prey they eat.

Six of the extant sea turtles are relatively small. Not small compared to regular turtles, small compared to the seventh living sea turtle, the leatherback. More about that one in a minute. The other six are the green, loggerhead, hawksbill, Kemp’s ridley and Olive ridley, and the flatback.

Let’s start with the green sea turtle, since I just mentioned it. Its shell is not always green. It can be brown or even black depending on where it spends most of its life. Green turtles that live in colder areas of the Pacific have darker shells, which probably helps them stay warm by absorbing more heat from sunlight. Young turtles have darker shells than old turtles for the same reason.

The green sea turtle can grow up to five feet long, or 1.5 meters, can live some 80 years, and mostly eats plants, especially seagrass, although babies eat small animals like worms, jellyfish, and fish eggs. A recent satellite tracking study of green sea turtles in the Indian Ocean tracked the turtles to a huge underwater seagrass meadow that no human realized existed until then. The meadows were farther underwater than the ones researchers knew about, up to 95 feet deep, or 29 meters. Researchers think the seagrass can grow at these depths because the water is so clear in the area, which means more light for the plants.

Unlike the green sea turtle, which lives throughout much of the world’s oceans, the flatback sea turtle is only found around Australia. It’s greenish or grayish and only grows around 3 feet long, or 95 cm, and eats invertebrates of various kinds, including jellyfish, shrimp, and sea cucumbers. It stays near shore in shallow water and doesn’t migrate, so it’s mostly safe from getting tangled in commercial fishing nets that kill a lot of other sea turtle species.

The smallest sea turtle is the olive ridley, which only grows around two feet long, or 60 cm. Its shell is roughly heart-shaped and is usually olive green. It mostly lives in tropical waters and is the most common sea turtle of all the living species, but getting rarer. It likes warm, shallow water and eats small animals like snails, jellyfish, and sea urchins.

Kemp’s ridley sea turtle is closely related to the olive ridley, and is not much larger. It grows to around 28 inches long, or 70 cm, and eats the same things as the olive ridley. It also likes the same warm, shallow waters, but it nests exclusively along the Gulf Coast of North America. Oil spills in the Gulf have killed so many turtles that the species is now listed as critically endangered. Conservationists sometimes remove eggs to safer, cleaner beaches where babies are more likely to hatch and survive. Besides oil spills and other types of pollution, Kemp’s ridley sea turtles are often killed when they get tangled in shrimp nets and drown. Fortunately, shrimp trawlers in the Gulf now use turtle excluders, which help keep turtles from getting tangled.

The hawksbill sea turtle grows to around three feet long, or 1 meter, and lives around tropical reefs. It has a more pointed, hooked beak than other sea turtles, which gives it its name. You might think it eats fish or something with a beak like that, but mostly it eats jellyfish and sea sponges. It especially likes the sea sponges, some of which are lethally toxic to most other animals. It also doesn’t have a problem eating even extremely stingy jellies and jelly-like animals like the Portuguese man-o-war. The hawkbill’s head is armored so the stings don’t bother it, although it does close its eyes while it chomps down on jellies. People used to kill hawksbill sea turtles for their multicolored shells, but don’t eat them. Its meat can be toxic due to the toxins it ingests.

The hawksbill is also biofluorescent! Researchers only found this out by accident in 2015, when a team studying biofluorescent animals in the Solomon Islands saw and filmed a hawksbill glowing like a UFO with neon green and red light. Researchers still don’t know why and how the hawksbill glows. They think the red color may be emitted by certain algae that grow on hawksbill shells, but the green appears to be emitted by the turtle itself. Since the hawksbill lives mostly around coral reefs, where many animals biofluoresce, researchers hypothesize it might be a way for the turtle to blend in. If everyone’s glowing, the big turtle-shaped spot that isn’t glowing would give it away. Then again, since male turtles glow more brightly than females, researchers also think it may be a way to attract mates.

Finally, the loggerhead sea turtle grows to a little longer than three feet, or 95 cm, and its shell is usually reddish-brown. It lives throughout the world’s oceans and while it nests in a lot of places, many loggerheads lay their eggs on Florida beaches. It eats invertebrates like bivalves and sponges, barnacles and jellyfish, starfish, plants, and lots of other things, including baby turtles. Its jaws are powerful and it has scales on its front flippers that stick out a little, called pseudoclaws, which allow it to manipulate its food or tear it into smaller pieces.

All sea turtles are endangered and are protected worldwide, although some countries enforce the protection more than others. Some people still eat sea turtles and their eggs, even though both can contain bacteria and toxic metals that make people sick. But mostly it’s habitat loss, pollution, and fishing nets and longlines that kill turtles.

People want to build houses on the beach, or drive their cars on the beach, and that destroys the habitat female turtles need to lay their eggs. Turtles also get stuck in fishing equipment and drown. And there’s so much plastic floating around in the sea that all sorts of animals are affected, not just turtles. A floating plastic bag or popped balloon looks like a jellyfish to a sea turtle that doesn’t know what plastic is. A turtle can eat so much plastic that its digestive system becomes clogged and it dies. One easy way you can help is to remember your reusable bag when you go shopping. The fewer plastic bags that are made and used, the fewer will find their way into the ocean. Some countries have banned plastic shopping bags completely.

Now let’s talk about the leatherback turtle. It’s much bigger than the others and not very closely related to them. It can grow some nine feet long, or 3 meters, and instead of having a hard shell like other sea turtles, its carapace is covered with tough, leathery skin studded with tiny osteoderms. Seven raised ridges on the carapace run from head to tail and make the turtle more stable in the water, a good thing because leatherbacks migrate thousands of miles every year. Not only is the leatherback the biggest and heaviest turtle alive today by far, it’s the heaviest living reptile that isn’t a crocodile. It has huge front flippers, is much more streamlined even than other sea turtles, and has a number of interesting adaptations to life in the open ocean.

The leatherback lives throughout the world, from warm tropical oceans up into the Arctic Circle. It mostly eats jellyfish, so it goes where the jellyfish go, which is everywhere. It also eats other soft-bodied animals like squid. To help it swallow slippery, soft food when it doesn’t have the crushing plates that other sea turtles have, the leatherback’s throat is full of backwards-pointing spines. What goes down, will not come back up, which is great when the turtle swallows a jellyfish, not so great when it swallows a plastic bag.

The leatherback can dive as deep as 4,200 feet, or almost 1,300 meters. Even most whales don’t dive that deep. But it’s a reptile, so how does it manage to survive in such cold water, whether in the Arctic Ocean or nearly a mile below the water’s surface?

The leatherback’s metabolic rate is high to start with, and it swims almost constantly. Its muscles generate heat as they work, which keeps the turtle’s body warmer than the surrounding water, as much as 30 degrees Fahrenheit warmer, or 18 degrees Celsius. Its flippers and throat also use a system called countercurrent heat exchange, where blood that has been chilled by outside temperatures returns to the heart in veins that surround arteries containing warm blood flowing from the heart. By the time the cool blood reaches the heart, it’s been warmed by the arterial blood. This keeps heat inside the body’s core.

Unlike other sea turtle species, leatherbacks don’t necessarily return to the same beach where they were hatched to lay their eggs. Females usually nest every two or three years and lay about 100 eggs per nest. No one is sure how long leatherbacks live, but it may be a very long time. Most turtles have long lifespans, and many sea turtle species don’t even reach maturity until they’re a couple of decades old.

One interesting thing about sea turtles, which is also true of many other reptiles, is that the temperature of the egg determines whether the baby turtle will develop into a male or female. Cooler temperatures produce mostly male babies, warmer temperatures produce mostly female babies. This is pretty neat, until you remember that the global temperature is creeping up. A new study of sea turtles around Australia’s northern Great Barrier Reef found that almost all baby turtles hatching there are now female—up to 99.1% of all babies hatched. Another study found the same results in sea turtle nests in Florida, where 97 to 100% of all babies are female. The studies also found that the amount of water in the nest’s sand also contributes to whether babies are male or female, with drier nests producing more females. Researchers are considering incubating some nests in climate-controlled rookeries to ensure that enough males hatch and survive to produce the next generation.

So those are the seven types of sea turtle alive today. Now let’s talk about an extinct sea turtle, a relative of the leatherback. This is archelon, and it was huge.

Archelon was the biggest turtle that has ever lived, as far as we know. The first fossil archelon was discovered in 1895 in South Dakota, in rocks that were around 75 million years old. The biggest archelon fossil ever found came from the same area, and measures 13 feet long, or 4 meters. It’s even broader from flipper to flipper, some 16 feet wide, or 5 meters. It lived in the shallow sea that covered central North America during the Cretaceous, called the Western Interior Seaway. I like that name. Its shell was leathery and probably flexible like the leatherback’s, but unlike the leatherback, it wasn’t teardrop shaped. In fact, it was very round. Since it lived at the same time as mosasaurs, its wide shell may have kept it from being swallowed by predators. It probably ate squid and jellyfish like the leatherback, and researchers think it was probably a slow swimmer. It went extinct at the same time as the dinosaurs, but fortunately its smaller relations survived.

We don’t know if that 13-foot-long archelon was an unusually large specimen, an average specimen, or a small specimen. It was probably on the large size, but it’s a good bet that there were larger individuals swimming around 75 million years ago. We don’t know if leatherbacks occasionally get bigger than nine feet long, for that matter. But we do have reports of sea turtles that are much, much bigger than any sea turtles known.

In August of 2008, a 14-year-old boy snorkeling in Hawaii reported swimming above a sea turtle that was resting on the bottom of a lagoon. He estimated the turtle was eight to ten feet across with a round shell. At the time he didn’t realize that was unusual. He also reported seeing a geometric pattern on the shell, which is not a feature of the leatherback or archelon but is present in other sea turtles. So if his estimation of size is correct, he saw a sea turtle far bigger than any living today.

In 1833, a schooner off the coast of Newfoundland came across what they thought was an overturned boat. When the crew investigated, they discovered it wasn’t a boat at all but an enormous leatherback turtle, which they reported was 40 feet long, or 12 meters.

Many sea serpent sightings may actually be misidentifications of sea turtles. Sea turtles do have relatively long necks which they can and do raise out of the water. A long neck with a small head sticking out of the water, with a hump behind it, describes a lot of sea serpent reports. It’s also possible that some sea serpent reports are actually sightings of sea turtles entangled with fishing nets and other debris that the turtle drags with it as it swims, which may look like a long snake-like tail behind a humped body.

For instance, in 1934 some fishermen off the coast of Queensland, Australia spotted what they thought was a sea serpent. I’ll quote the description, which is from an article with the lengthy title of “Historicity of Sea Turtles Misidentified as Sea Monsters: A Case for the Early Entanglement of Marine Chelonians in Pre-plastic Fishing Nets and Maritime Debris” by Robert France. I’ll put a link in the show notes in case you want to read the article, if I can find it again. I printed it out so I could keep it.

Anyway, the fishermen reported that the sea serpent looked like this:

“The head rose about eight feet out of the water, and resembled a huge turtle’s head…the colour was greyish-green. The eye…was small in comparison to the rest of the monster. The other part in view was three curved humps about 20 feet apart, and each one rose from six feet in the front to a little less in the rear. They were covered with huge scales about the size of saucers, and also covered in barnacles. We could not get a glimpse of the tail, as it was under the water.”

Robert France suggests that this was a sea turtle entangled with a string of fishing gear, specifically fishing floats. He also gives a number of other examples dating back hundreds of years. Fortunately for sea turtles and other animals in the olden days, most fishing nets were made from rope, usually hemp and sometimes cotton, which eventually rotted and freed the animal, if it survived being entangled for months on end.

So if you live around the ocean, or any kind of water for that matter, make sure to pick up any litter you find, especially plastic bags. You could save a lot of lives. Who knows, maybe the sea turtle you save from eating that one fatal plastic bag will grow up to become the biggest sea turtle alive.

As a companion piece to this episode, Patreon subscribers got an episode about the Soay Island Sea Monster sighted in 1959, which was probably a sea turtle of some kind. Just saying.

You can find Strange Animals Podcast online at We’re on Twitter at strangebeasties and have a facebook page at If you have questions, comments, or suggestions for future episodes, email us at If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 074: Colossal Squid and the Things That Eat Them

We’re going to learn about the colossal squid in this episode, with bonus info about the giant squid…and then we’re going to learn about the massive things that eat this massive squid!

A giant squid, looking slightly guilty for eating another squid:

A colossal squid, looking less than impressive tbh:


A sperm whale looking baddass:

A southern sleeper shark, looking kind of boring:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week we’re going to learn first about the colossal squid, and then we’re going to learn about what eats the colossal squid.

You’ve probably heard of the giant squid, but maybe you haven’t. Let’s start with it, because the giant squid and the colossal squid are both massive, amazing deep-sea animals.

Stories of huge squid go back to ancient times. Aristotle and Pliny wrote about it, the legend of the kraken may be at least partially inspired by it, and sailors have told stories about it for time out of mind. Naturalists of the mid-19th century knew it must exist because whalers had found enormously long tentacles and huge beaks in sperm whale stomachs. But except for the occasional badly damaged specimen washed up on shore, no one had seen a giant squid. Certainly no one had seen a living giant squid.

It wasn’t until 2001 that a live giant squid was caught on film, and then it was only a larval squid. In 2002 a live adult giant squid was caught off the coast of Japan. It wasn’t especially big, just 13 feet long, or 4 meters, but up until then an adult giant squid had never been captured or even photographed. Its body is now on display at the National Science Museum of Japan. It wasn’t until 2004 that a research team got photographs of a live giant squid in its natural habitat, also off the coast of Japan. Since then researchers have taken more photographs and footage of giant squid, and we’re starting to learn more about it.

Squids in general have a body called a mantle, with small fins at the rear and eyes near the base above the arms, eight arms, and two long tentacles. The arms and tentacles are lined with suction cups that contain rings of serrated chitin, which allows the squid to hang on to its prey. Chitin is the same stuff lobster shells and fish scales are made of. It’s the invertebrate version of keratin. In the middle of the arms, at the base of the mantle, is the squid’s mouth, which looks for all the world like a gigantic parrot beak, also made of chitin. Instead of actual teeth, the squid has a radula, which is basically a tongue studded with chitinous teeth that it uses to shred its prey into pieces small enough to swallow.

Most of the length of a giant squid comes from its tentacles. Researchers estimate that the longest giant squid’s mantle is about 7 ½ feet long, or 2.25 meters. The longest giant squid’s mantle and arms together reach around 16 feet long, or 5 meters. That’s still pretty huge, but it’s not until you add in the tentacles that the length just gets ridiculous. The longest giant squid known—and this is an estimate based on the size of the biggest beak ever found—was 43 feet, or 13 meters. Females are typically much bigger than males and can weigh twice as much.

The giant squid is a deep-sea animal, probably solitary, and eats fish and smaller squid, including other giant squid. It’s an active hunter and catches prey by grabbing it with its super-long tentacles, reeling it in to hold it more securely with its arms, then biting it with its beak and shredding it into pieces with its radula.

The giant squid has the largest eye of any living animal, as big as 11 inches in diameter, or 27 cm. Since it mostly lives in the deep sea, it probably needs such big eyes to see bioluminescent light given off by the animals it eats and to detect predators. Only ichthyosaurs had larger eyes. Well…except for the colossal squid, which may have eyes even bigger than the giant squid’s.

So if the giant squid can grow to some 43 feet long, is the colossal squid even longer? Only a little. Researchers estimate the colossal squid can grow to around 46 feet long, or 14 meters, but it has shorter tentacles and a much longer mantle than the giant squid so is an overall much bigger and heavier animal.

But that size estimate is only that, an estimate. We know very little about the colossal squid. It was first described from parts of two arms found in the stomach of a sperm whale in 1925, and for more than 50 years that was pretty much all we had. Then a Russian trawler caught an immature specimen in 1981 off the coast of Antarctica. Since then researchers have been able to study a few other specimens caught or found dead, mostly from the Antarctic seas.

As far as we know, the colossal squid is an ambush predator rather than an active hunter like the giant squid. It lives in the deep seas in the Southern Ocean, especially around Antarctica, as far down as 7,200 feet or 2.2 km beneath the surface of the ocean, and it mostly eats fish. While its tentacles are much shorter than the giant squid’s, they have something the giant squid does not. Its suckers have hooks, some of them triple-pointed and some of which swivel. When it grabs onto something, it is not going to let go until somebody gets eaten.

The largest colossal squid ever found was caught in 2007 in the Antarctic. It was caught by a trawler when they hauled in a fishing line. The squid was eating an Antarctic toothfish caught on the line and wouldn’t let go, so the fishermen hauled it aboard in a net and froze it. It was 33 feet long, or ten meters, and by the time it was thawed out for study, its tentacles had shrunk so that it was even shorter. Its eye was 11 inches across, or 27 cm, but when the squid was alive its eye was probably bigger, maybe as much as 16 inches across, or 40 cm—in which case, it wins the biggest eye category and deserves a trophy. With an eyeball on it.

So if the biggest colossal squid we’ve ever seen is only 33 feet long, how do we know it can grow to 46 feet long? Because whalers have found colossal squid beaks in the stomachs of sperm whales that are much larger than the 33-foot squid’s beak.

And that brings us to the first predator of the colossal squid, the sperm whale. Lots of things eat young colossal squids, from fish and albatrosses to seals and bigger squids, but today we’re talking about predators of full-grown colossal squid. There aren’t many. In fact, there are only two that we know of.

The sperm whale eats pretty much anything it wants, frankly, but mostly what it wants is squid. It eats both giant and colossal squid, and we know because squid beaks aren’t digestible. They stay in the whale’s stomach for a long time. Specifically they stay in the whale’s second stomach chamber, because sperm whales have a four-chambered stomach like cows and other ruminants do. Sometimes a whale will puke up squid beaks, but often they just stay in the stomach. Some whales have been found with as many as 18,000 squid beaks in their stomachs. 18,000! Can you imagine having 18,000 of anything riding around in your stomach? I wouldn’t even want 18,000 Cap’n Crunches in my stomach and I really like Cap’n Crunch cereal.

Sometimes squid beaks do make it deeper into the whale’s digestive system, and when that happens, researchers think it stimulates the body to secrete a greasy substance called ambergris to coat the beak so it won’t poke into the sides of the intestines. Small lumps of ambergris are sometimes found washed up on shore after the whale poops them out, and it can be valuable. Once it’s been out of the whale for a while it starts to smell really good so has been traditionally used to make perfume, but these days most perfume companies use a synthetic version of ambergris.

The sperm whale can grow to at least 67 feet long, or 20.5 meters, and may possibly grow much longer. It’s an active hunter and a deep diver, with the biggest whales routinely diving to almost 7,400 feet or 2,250 meters to catch that tasty, tasty squid. It can stay underwater for over an hour. It has teeth only in the lower jaw, which is long and thin. The upper jaw has holes in the gum called sockets where its lower teeth fit into, which is kind of neat. But because male sperm whales sometimes fight by ramming each other, occasionally a whale’s jaw will become broken, dislocated, or otherwise injured so that it can’t use it to bite squid. But that actually doesn’t seem to stop the whale from eating squid successfully. They just slurp them up.

Sperm whales use echolocation to find squid, but researchers also think the whale can use its vision to see the squid silhouetted against the far-off water’s surface. Sperm whales have big eyes, although not nearly as big as squid eyes, and a whale can retract its eyeballs into its eye sockets to reduce drag as it swims. It can also protrude its eyes when it wants to see better. Researchers have tagged sperm whales with radio transmitters that tell exactly where the whale is and what it’s doing, at least until the tag falls off. The tags occasionally show that a sperm whale will hunt while swimming upside down, which researchers think means the whale is looking up to see squid silhouettes.

You’ll often hear people talk about sperm whales and giant squids battling. Sperm whales do often have sucker marks and scars from giant and colossal squid arms, but that doesn’t mean the squid was trying to drown the whale. Squid have no real defense against getting eaten by sperm whales. All a squid can do is hang on to the whale in hopes that it won’t actually end up in the whale’s belly, which is not going to happen, squid. Some researchers even theorize that the sperm whale can stun prey with a massive burst of powerful sonar impulses, but so far there’s no evidence for this frankly pretty awesome hypothesis.

The other main predator of full-grown colossal squid are a few species of sharks called sleeper sharks. They’re slow-moving deep-sea sharks that mostly live in cold waters around the Arctic and Antarctic. We don’t know much about a lot of sleeper sharks species. Many of them were only discovered recently, and some are only known from one or a few specimens. Sleeper sharks are generally not much to look at. They don’t have great big mouths full of huge teeth like great whites, they don’t have weird-shaped heads like hammerheads, and they’re just plain grayish all over, maybe with some speckles.

The Greenland shark is one type of sleeper shark. It’s the one with the longest known lifespan of any vertebrate, as much as 500 years old. The Greenland shark is also one of the largest sharks alive, up to 24 feet long, or 7.3 meters, and possibly longer. But the Greenland shark isn’t one of the sleeper sharks that eat colossal squid, since it lives around the Arctic and the colossal squid lives around the Antarctic. But the Southern sleeper shark lives around the Antarctic and is so closely related to the Greenland shark that for a long time many researchers thought it was the same species. The Southern sleeper shark is overall shorter, only around 14 feet long, or 4.4 meters, although since we don’t know a lot about it, we don’t really know how big it can get. It’s probably an ambush predator and it definitely eats colossal squid because colossal squid beaks are sometimes found in its stomach.

In 2004 a team of researchers examined the stomach contents of 36 sleeper sharks that had been accidentally killed by fishing trawlers around and near Antarctica. They found remains of at least 49 colossal squid, bigger on average than the squid sperm whales typically eat.

Just going by what we know about the Greenland shark, it’s safe to say that the southern sleeper shark is an extremely slow swimmer, barely exceeding more than two miles an hour, or 3.5 km per hour. That’s about the speed you walk if you’re not in any particular hurry. It may also be prey to the same parasitic copepod, which is a type of crustacean, that infests a lot of Greenland sharks. The parasite attaches itself to the shark’s EYEBALL. But some researchers think the parasite actually gives something back to the shark, by glowing with a bioluminescence that attracts prey, which the shark then eats. Greenland sharks don’t appear to need to see in order to find prey anyway. That doesn’t make it any less gross.

I’m very sorry to end this episode with an eyeball parasite, so here’s one last thing to take your mind off it. As long as there have been reports of gigantic squid, there have been reports of gigantic octopuses. The largest octopus currently known is the giant Pacific octopus with a 20 foot legspan, or 6 meters. But there may be a gigantic octopus much larger than that. In 1928, six octopuses were sighted off the coast of Oahu in Hawaii by a sailor in the US Navy, who estimated their legs spanned 40 feet across, or 12.5 meters. In 1950, a diver in the same area reported seeing an octopus with a body the size of a car, and with tentacles estimated as 30 feet long each, or 9.3 meters.

Remember the study I mentioned earlier, about researchers finding lots of colossal squid remains in sleeper shark stomachs? They found something else in one of the sharks, remains of a huge octopus. Species unknown.

You can find Strange Animals Podcast online at We’re on Twitter at strangebeasties and have a facebook page at If you have questions, comments, or suggestions for future episodes, email us at If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 067: More Sea Monsters

Finally, it’s the follow-up to our first sea monsters episode that sounds so terrible now that I know how to put a podcast together!

Here’s the published drawings of a strange animal seen from the HMS Daedalus:

Here’s Drummond’s sketch of what he saw:

Here’s a sketch of the HMS Plumper animal sighted:

And here’s a sei whale rostrum sticking up out of the water while it’s skim feeding:

Sei whales are neat and have gigantic mouths:

The rotten “sea serpent” that’s actually a decomposing baleen whale:

The Naden Harbour Carcass. It’s the black thing on the table with a white backdrop. It doesn’t look like much, but you probably wouldn’t look like much either after being eaten by a sperm whale:

Unexpected seal says “Hello, I am not a sea serpent, I am a stock photo”:

Hagelund’s sketch of the little animal he caught:

A pipefish with a lollipop tail and some drawings of pipefish:

The strange animal seen from the Valhalla:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

Recently I listened to episode six, about sea monsters. It’s climbed to our third most popular episode and when I heard it again, oh man, I winced. I was still really new to podcasting then and that episode sounds like someone reading a book report out loud to the class. So it’s time to do a new sea monsters episode and explore more mysteries of the world’s oceans, hopefully with a lot more vocal expression.

On August 6, 1848, about 5 o’clock in the afternoon, the captain and some of the crew of HMS Daedalus saw something really big in the water. The ship was sailing between the Cape of Good Hope and St. Helena on the way back to England from the East Indies. It was an overcast day with a fresh wind, but nothing unusual. The midshipman noticed something in the water he couldn’t identify and told the officer of the watch, who happened to be walking the deck at the time with the captain. Most of the crew was at supper.

This is what the captain, Peter M’Quhae, described in his report when the ship arrived at Plymouth a few months later.

“On our attention being called to the object, it was discovered to be an enormous serpent, with head and shoulders kept about four feet constantly above the surface of the sea, and, as nearly as we could approximate, by comparing it with the length of what our main-topsail yard would show in the water, there was at the very least sixty feet of the animal à fleur d’eau [that means at the water’s surface], no portion of which was, to our perception, used in propelling it through the water, either by vertical or horizontal undulation. It passed rapidly, but so close under our lee quarter, that had it been a man of my acquaintance, I should easily have recognized his features with the naked eye; and it did not, either in approaching the ship or after it had passed in our wake, deviate in the slightest degree from its course to the S.W., which it held on at the pace of from twelve to fifteen miles per hour, apparently on some determined purpose.

“The diameter of the serpent was about fifteen or sixteen inches behind the head, which was, without any doubt, that of a snake; and it was never, during the twenty minutes that it continued in sight of our glasses, once below the surface of the water; its colour a dark brown, with yellowish white about the throat. It had no fins, but something like a mane of a horse, or rather a bunch of seaweed, washed about its back.”

The original Times article also mentioned large jagged teeth in a jaw so large that a man could have stood up inside the mouth, but this seems to be an addition by the article’s writer, not the captain or crew.

The officer of the watch, Lieutenant Edgar Drummond, also published an excerpt from his own journal about the sighting, which appeared in a journal called the Zoologist in December 1848. It reads, “In the 4 to 6 watch, at about five o’clock, we observed a most remarkable fish on our lee quarter, crossing the stern in a S.W. direction; the appearance of its head, which, with the back fin, was the only portion of the animal visible, was long, pointed, and flattened at the top, perhaps ten feet in length, the upper jaw projecting considerably; the fin was perhaps twenty feet in the rear of the head, and visible occasionally; the captain also asserted that he saw the tail, or another fin about the same distance behind it; the upper part of the head and shoulders appeared of a dark brown colour, and beneath the under jaw a brownish white. It pursued a steady undeviating course, keeping its head horizontal with the surface of the water, and in rather a raised position, disappearing occasionally beneath a wave for a very brief interval, and not apparently for purposes of respiration. It was going at the rate of perhaps from twelve to fourteen miles an hour, and when nearest, was perhaps one hundred yards distant. In fact it gave one quite the idea of a large snake or eel. No one in the ship has ever seen anything similar, so it is at least extraordinary. It was visible to the naked eye for five minutes, and with a glass for perhaps fifteen more. The weather was dark and squally at the time, with some sea running.”

To translate some of this into metric, 60 feet is a little more than 18 meters, the 15 inch diameter the captain reported of the neck just behind the head is about 38 cm, and the speed of 13 mph is almost 21 km per hour.

A lot of people wrote in to the Times to discuss the sighting and suggest solutions. One writer claimed the animal couldn’t be a snake or eel, since a side to side undulating motion would have been obvious as the animal propelled itself with its tail. Another said it had to have been a snake but the undulations were only in the tail, which was below the water. Yet another article suggested it was a monstrous seal or other pinniped. Captain M’Quhai took exception to that one and wrote back stressing that he was familiar with seals and this definitely had not been one. Other suggestions included a basking shark or some other unknown species of shark, a plesiosaur, or a giant piece of seaweed.

Other similar sightings are on record, including a very similar one from the very end of 1849 off the coast of Portugal. In that one, an officer on HMS Plumper reported seeing “a long black creature with a sharp head, moving slowly, I should think about two knots, through the water, in a north westerly direction, there being a fresh breeze at the time, and some sea on. I could not ascertain its exact length, but its back was about twenty feet if not more above water; and its head, as near as I could judge, from six to eight. I had not time to make a closer observation, as the ship was going six knots through the water, her head E. half S., and wind S.S.E. The creature moved across our wake towards a merchant barque on our lee-quarter, and on the port tack. I was in hopes she would have seen it also. The officers and men who saw it, and who have served in parts of the world adjacent to whale and seal fisheries, and have seen them in the water, declare they have neither seen nor heard of any creature bearing the slightest resemblance to the one we saw. There was something on its back that appeared like a mane, and, as it moved through the water, kept washing about, but before I could examine it more closely, it was too far astern.”

Illustrations of the Daedalus sea serpent, which M’Quhai approved, were published in the Times. But the original sketch made by Drummond in his journal the day he saw the animal gives us a much better idea of what it looked like and what it probably was. The sketch accompanying the Plumper sighting reinforces the solution. It’s probable that both sightings, and probably many others, were of a sei whale skim feeding.

The sei is a baleen whale that’s generally considered the fourth largest whale, with some individuals growing almost 65 feet long, or nearly 20 meters. Females are larger than males. It lives all over the world although it likes deep water that isn’t too cold or too hot. It’s a mottled dark grey. Its fins are relatively short and pointed, its dorsal fin is tall and fairly far back on the animal’s body. Its tail flukes aren’t usually visible. Its rostrum, or beak, is pointed and short baleen plates hang down from it. The sei whale’s baleen is unusually fine, with a fringe that is curly and white and looks something like wool.

Unlike some whales, it doesn’t dive very deeply or for very long, and it’s usually relatively solitary. It spends a lot of its time at or near the surface, frequently skim feeding to capture krill and other tiny food. It does this by cruising along with its mouth open, often swimming on its side. It has throat pleats that allow its huge mouth to expand and hold incredible amounts of water. The whale closes its mouth and raises its huge tongue, forcing the water out through its baleen plates. Whatever krill and fish are caught by the baleen, the whale swallows.

A lot of baleen whales skim feed occasionally, but the sei is something of a skim feeding specialist. And it has a narrow, pointed rostrum that often sticks up out of the water as it skim-feeds, with pale baleen hanging down. This might easily look like a long snakey animal with a small head held up out of the water, especially in poor viewing conditions when the people involved are convinced they’re looking at a sea serpent. The sei whale is a fast swimmer too, easily able to cruise at the speeds described by the Daedalus and Plumper crews.

It’s not a perfect match, of course. The sei whale’s dorsal fin is pretty distinctive and if seen properly would have immediately told the crew they were looking at a whale. No one reported seeing anything that could be considered a whale’s breath either, sometimes called a spout. Since whales exhale forcefully and almost empty their lungs when they do, the cloud of warm air expelled looks like steam and is a tell-tale sign of a whale. Whales also don’t have hair on their rostrum that could wash around like a mane on a sea serpent’s neck. So while it seems likely that the Daedalus and Plumper sightings were of sei or other baleen whales skim feeding, we can’t know for sure.

Incidentally, the sei whale wasn’t fully protected from whaling until 1986. Japan still hunts sei whales, supposedly for scientific purposes but no one’s really fooled. The whales they catch are sold for meat. In 2010, a restaurant in Los Angeles closed after being caught serving sei whale meat. The sei whale is still endangered but if people would stop killing it maybe it would be doing better. Whalers reported that when harpooned, sei whales would cry audibly, which apparently disturbed the whalers. Maybe if your job involves making animals cry you should go back to school and get a degree in nursing or teaching or something else that will make the world a better place, not worse.

Another whale is responsible for a mystery carcass washed up in the Philippines in 2017. The carcass looks like a dragon-like sea monster, but that’s due to decomposition. It’s actually a baleen whale, probably a gray whale, that had apparently been floating around for a while, getting nastier and more nibbled on every day.

Speaking of nasty, nibbled-on dead things, and whaling, in 1937 a sperm whale brought to Naden Harbor Whaling Station on a small Canadian island for processing turned out to have something so extraordinary in its stomach that the whalers took pictures of it. It was about ten feet long, or three meters, with a head said to be horselike or camel-like in shape with a drooping nose. Its body was long and thin, and it had short pectoral flippers and a single fluke or spade-shaped end on its tail. Its skin was either smooth or furry depending on which witness you believe, and there were signs it may have had baleen or gill rakers.

The carcass wasn’t kept, but pieces of it were reportedly sent to the British Columbia Provincial Museum, whose museum director suggested it might be a fetal baleen whale. Locals thought it might be a young cadborosaurus, a sea serpent occasionally sighted off the coast of British Columbia. It gets its name from Cadboro Bay, and is usually called Caddy. Caddy is generally described as 5 to 15 meters long, or 16 to almost 50 feet long, with a horse-like or camel-like head, big eyes, and a tail with horizontal flukes like a whale’s. Some witnesses say it has brown fur and horns or ears of some kind.

In 1992, a retired museum researcher named Ed Bousfield found three photos of the Naden Harbor carcass, long believed lost. This sparked up lots of debate, naturally, and lots of suggestions as to what the animal might be—a basking shark, a sea lion or other pinniped, an eel, an oarfish, and many others.

The problem, of course, is that the pictures aren’t very clear, we don’t have the actual body to examine, and the carcass had spent some time in the belly of a sperm whale so was in the process of being digested. But the whalers who found it had never seen anything like it before.

In 1968, a man called William Hagelund was yachting with his family when he heard splashing and saw a strange creature in the water. It was small, only about 16 inches long, or 40 cm, so he lowered a dinghy and caught it in a net. It had what appeared to be armored plates on its back, its flippers were odd-shaped, its snout was elongated but widened at the end, and it had a downy yellow fuzz or fur underneath. Hagelund put it in a bucket but it was so frantic to get out that he worried it would die. He made a drawing of it and released it.

Hagelund thought he’d caught a baby Caddy. But he didn’t share his story until twenty years later, when he wrote a book called Whalers No More.

But while Hagelund’s creature probably wasn’t a baby Caddy, it might have been something almost as strange. The pipefish is a fish related to the seahorse, and it resembles a seahorse that has straightened out. Some species have prehensile tails, some have little paddles at the end of their tails. Some are stripey. Like seahorses, the pipefish male has a brood pouch where he broods the female’s fertilized eggs. Not only does he protect the eggs, he supplies them with nutrients from his body while they grow. Because the female can lay more eggs than the male can hold in his brood pouch, females of some species of pipefish will have more than one mate. Pipefish rarely grow longer than around 16 inches, or 40 cm and have armored plating. The yellow fuzz Hagelund reported might have been algae.

It’s probable that at least some Caddy sightings are of moose swimming to or from one of the many small islands in the area. Moose will also dive to reach aquatic plants. Other Caddy sightings are probably of the Northern sea lion or Northern elephant seal, both of which are common in the area for at least part of the year.

Pinnipeds, in fact, may be the biggest factor to consider in any sea serpent or sea monster sightings. I learned this interesting fact after doing the research for the previous sea monster episode, but pinnipeds will stand vertically in the water to look around above the surface, and a big elephant seal can raise its head over three feet, or one meter, out of the water. If you’re in a boat and a big head and neck pops up out of the water nearby, your first thought is not going to be, “Oh, that’s an unexpected seal.” It’s going to be, “THIS GIANT ANIMAL IS GOING TO EAT ME.”

But that doesn’t mean there aren’t definite sea monsters out there. Far from it. On December 7, 1905, two naturalists spotted an animal they couldn’t recognize off the coast of Brazil.

The pair were Michael Nicholl and Edmund Meade-Waldo, part of a research team on the Valhalla. The ship was about 15 miles, or 24 km, from the mouth of the Parahiba River. At 10:15 a.m. Nicoll spotted a dorsal fin above the water that he didn’t recognize, about 100 yards away, or 91 meters. He asked Meade-Waldo to take a look, and he couldn’t identify the fish either. The fin was roughly rectangular, close to two feet high and six feet long, or 61 cm and 1.8 meters, and dark brown with an edge Meade-Waldo described as crinkled.

Meade-Waldo was looking at the fin through his binoculars when a head and long neck emerged from the water in front of the fin. He estimated it as 7 or 8 feet high, or over 2 meters, with a brown, turtle-like head. The animal moved its neck from side to side. They watched it until it was out of sight as the ship sailed away, but early the next morning, around 2 am, three crew members spotted what they thought was the same animal swimming underwater.

Nicholl and Meade-Waldo published their report in 1906. We still have no idea what they saw.

You can find Strange Animals Podcast online at We’re on Twitter at strangebeasties and have a facebook page at If you have questions, comments, or suggestions for future episodes, email us at If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 049: The Brantevik Eel and Friends

This week’s episode is about some interesting eels, including the Brantevik eel.

A European eel:

A leptocephalus, aka an eel larva:

A moray eel. It has those jaws you can see and another set of jaws in its throat:

Episode transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week, we’re going to learn about the Brantevik eel and some other eels, including an eel mystery.

The Brantevik eel is an individual European eel, not a separate species. Its friends knew it as Åle, which I’ve probably misprounounced, so I’m nicknaming it Ollie. So what’s so interesting about Ollie the eel?

First, let’s learn a little bit about the European eel in general to give some background. It’s endangered these days due to overfishing, pollution, and other factors, but it used to be incredibly common. It lives throughout Europe, from the Mediterranean to Iceland, and has been a popular food for centuries.

The European eel hatches in the ocean into a larval stage that looks sort of like a transparent flat tadpole, shaped roughly like a leaf. Over the next six months to three years, the larvae swim through the ocean currents, closer and closer to Europe, feeding on microscopic jellyfish and plankton. Toward the end of this journey, they grow into their next phase, where they resemble eels instead of tadpoles, but are mostly transparent. They’re called glass eels at this point. The glass eels make their way into rivers and other estuaries and slowly migrate upstream. Once a glass eel is in a good environment it metamorphoses again into an elver, which is basically a small eel. As it grows it gains more pigment until it’s called a yellow eel. Over the next decade or two it grows and matures, until it reaches its adult length—anywhere from two to five feet, or 60 cm to 1.5 meters. When it’s fully mature, its belly turns white and its sides silver, which is why it’s called a silver eel at this stage. Silver eels migrate more than 4,000 miles, or 6500 km, back to the Sargasso Sea to spawn, lay eggs, and die.

One interesting thing about the European eel is that during a lot of its life, it has no gender. Its gender is determined only when it grows into a yellow eel, and then it’s mostly determined by environmental factors, not genetics.

Until the late 19th century, everyone thought these different stages—larva, glass eel, elver, yellow eel, and silver eel—were all separate animals. No one knew how or even if eels reproduced. The ancient Greeks thought eels were a type of worm that appeared spontaneously from rotting vegetation. Some people thought eels mated with snakes or some types of fish. By the 1950s the eel’s life cycle was more or less understood, but many researchers thought the European eels never made it to the Sargasso Sea to spawn. It was just too far, so they thought the eels that arrived in Europe were all larvae of the American eel, which is almost identical in appearance to the European eel. The Sargasso Sea is off the coast of the Bahamas, so the American eel doesn’t have nearly as far to travel. These days we know from DNA studies that the American and European eels are different species. The European eel is just a world-class swimmer.

European eels are nocturnal and may live in fresh water, brackish water, or sometimes they remain in the ocean and live in salt water, generally in harbors and shallows. They eat anything they can catch, from fish to crustaceans, from insect larvae to dead things, and on wet nights they’ll sometimes emerge from the water and slide around on land eating worms and slugs. Many populations don’t eat at all during the winter.

Now, back to the Brantevik eel. Brantevik is a tiny fishing village in Sweden. In 1859, an eight-year-old boy named Samuel Nilsson caught an eel and released it into his family’s well to eat insect larvae and other pests. This was a common practice at the time when water wasn’t treated, so the fewer creepy-crawlies in the water, the better.

And there the eel stayed. Ollie got famous over the years, at least in Sweden. Its 100th well anniversary was celebrated in 1959, and children’s books and even movies featured it. But in summer of 2014, Ollie died. Its well is now on the property of Tomas Kjellman, whose family bought the cottage and its well in 1962. Everyone knew about the resident eel, which the family treated as something of a pet. In fact, they discovered it was dead when they opened the well’s cover to show the eel to some visiting friends.

Ollie’s remains were removed from the well and shoved in the family’s freezer, and later sent to be analyzed at the Swedish University of Agricultural Science’s Institute of Freshwater Research. That analysis confirmed that Ollie was over 150 years old.

In the wild, European eels don’t usually live longer than twenty years, and ten years is more likely. But in captivity, where eels don’t spawn, they can live a long time. A female European eel named Putte lived over 85 years in an aquarium at Halsinborgs Museum in Sweden.

What most people don’t know is that Ollie wasn’t alone. Another eel still lives in the well and is doing just fine, but it’s younger, only about 110 years old.

The larvae of European eels are small, only about three inches at the most, or 7.5 cm. Even conger eel larvae are small, only 4 inches long, or 10 cm, and conger eels can grow 10 feet long, or 3 meters. But on January 31, 1930, a Danish research ship caught an eel larva 900 feet deep off the coast of South Africa—and that larva was six feet 1.5 inches long, or 1.85 meters.

Scientists boggled at the thought that this six-foot eel larva might grow into an eel more than 50 feet long, or 15 meters, raising the very real possibility that this unknown eel might be the basis of many sea serpent sightings.

The larva was preserved and has been studied extensively. In 1958, a similar eel larva was caught off New Zealand. It and the 1930 specimen were determined to belong to the same species, which was named Leptocephalus giganteus. Leptocephalus, incidentally, is a catchall genus for all eel larvae, which can be extremely hard to tell apart.

In 1966 two more of the larvae were discovered in the stomach of a western Atlantic lancet fish. They were much smaller than the others, though—only four inches and eleven inches long, or 10 cm and 28 cm. Dr. David G. Smith, an ichthyologist at Miami University, determined that the eel larvae were actually not true eels at all, but larvae of a spiny eel. Deep-sea spiny eels are fish that look like eels but they’re not closely related. And while spiny eels do have a larval form that resembles that of a true eel, they’re much different in one important way. Spiny eel larvae grow larger than the adults, then shrink when they develop into their mature form.

So the six-foot eel larvae, if it had lived, would have eventually developed into a spiny eel no more than six feet long itself at the most, and probably shorter.

More recent research has called Dr. Smith’s findings into question, and many scientists today consider L. giganteus to be the larvae of a short-tailed eel, which is a true eel—but not a type that grows much larger than its larvae. So either way, the adult form would probably not be much longer than a conger eel.

But…we still don’t have an adult. So there’s still a possibility that a very big deep-living marine eel is swimming around in the world’s oceans right now.

The longest known eel is the slender giant moray, which can reach 13 feet in length, or 4 meters. Morays are interesting eels for sure. They live in the ocean, especially around coral reefs, and have two sets of jaws, their regular jaws with lots of hooked teeth, and a second set in the throat that are called pharyngeal jaws, which also have teeth. The moray uses the second set of jaws to help grab and swallow prey that might otherwise wriggle out of its mouth. The moray has a strong bite and doesn’t see very well, although its sense of smell is excellent. This occasionally causes problems for divers who think it would be fun to feed an eel and end up with a finger bitten off. Don’t feed the eels, okay? Not only that, but a moray can’t release its bite even if it’s dead, so if one bites a diver, someone has to pry the eel’s jaws open before the bite can be treated. And as if all that wasn’t warning enough to not feed wild animals, and frankly just stay out of the water entirely, research suggests that some morays are venomous. Oh, and the giant moray sometimes hunts with a fish called the roving coralgrouper, which grows to some four feet long, or 120 cm, which is a rare example of interspecies cooperative hunting.

Some people believe that at least some sightings of the Loch Ness monster can be attributed to eels—European eels, in this case. An eel can’t stick its head out of the water like Nessie is supposed to do, but it does sometimes swim on its side close to the water’s surface, which could result in sightings of a string of many humps undulating through the water. But while eels do live in and around Loch Ness, it’s unlikely that any European eel would grow much larger than around five feet, or 1.5 meters. Still, you never know. Loch Ness is the right habitat for an eel to grow to its maximum size, and while we have learned a lot about eels in general, and the European eel in particular, since Ollie was released into a well in Brantevik, we certainly don’t know everything about them.

One last note about eel larvae. Occasionally on facebook and other social media, well-meaning people will share warnings about a nearly invisible wormlike parasite that can be found in drinking water, with pictures of, you guessed it, eel larvae. Eel larvae are not parasites, are not found in fresh water at all, and even if you did accidentally swallow one, you’d just digest it and get a little protein out of the bargain. So you don’t need to worry about those clickbait warnings, the eels do.

You can find Strange Animals Podcast online at We’re on Twitter at strangebeasties and have a facebook page at If you have questions, comments, or suggestions for future episodes, email us at If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or whatever platform you listen on. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 016: Jellyfish

If you look at this episode and think, “Oh, ho hum, think I’ll skip this one because snore, jellyfish,” you are so wrong! Jellies are fascinating, creepy, and often beautiful. Come learn all about our squishy friends in the sea!

A Portuguese man o’war. Creepy as heck:

A lion’s mane jelly. You do not want this guy on your ship. Incidentally, a lot of the photos you find of divers with enormous lion’s mane jellies are fakes that make the jellies look gigantic.

The cosmic jelly, a deep-sea creature:

The creepy Stygiomedusa gigantea, guardian of the underworld:

A newly discovered golden jelly.

Further reading:

Jelly Biologist (I’ve been enjoying browsing this site)

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week’s episode is about jellyfish—also called jellies, which is more accurate since they’re not fish at all.

Originally, I was going to focus on the Portuguese man o’war, another in the ongoing feature of “animals that scared me as a kid” and technically not even a jelly. But there’s so much to learn about jellies that we’re going to cover a whole lot more than that.

Jellies are interesting animals, to say the least. Their bodies have radial symmetry, meaning they’re the same in all directions. While the body shape varies, most jellies have a bell-like shape. The bell is generally rather thin, made up of an external covering, an internal covering, and an elastic gel-like material in between. Inside, the jelly has a digestive cavity with four to eight oral arms surrounding the mouth and long tentacles hanging beneath. The jelly also has a simple nerve net that can detect light and react to other stimuli, and which takes the place of a brain.

Jellies don’t have brains. They don’t have hearts, specialized sensory organs, or much of anything else. But they’ve been around for some 650 million years, possibly much longer, so clearly it all works.

The jelly’s life cycle is pretty weird. Most start out as polyps that stick to rocks or shells and use their little tentacles to catch microscopic organisms. A polyp can bud, producing new polyps that are clones of the original. Eventually, a polyp will constrict its body and develop into a stack of larvae. Each larva develops into a tiny jelly, which separates from the stack and swims away.

Once it’s grown, a jelly reproduces by releasing sperm, if it’s male, which the water carries to the female to fertilize her eggs. Some female jellies have brood pouches on the oral arms, some just carry the fertilized eggs inside the body while they develop. The embryos develop into swimming larvae called planula, which leave the female and attack themselves to something firm, where they transform into polyps.

This seems needlessly complicated, but again, it works for the jelly.

Polyps can live for years, while adult jellies, which I’m delighted to report are called medusas, usually only live a few months. The immortal jellyfish throws another step into this process. It can transform back into a polyp from any stage of its life if it needs to. As a polyp, the immortal jellyfish is tiny, only about a millimeter long. As a full-grown medusa it’s not all that much bigger, less than four millimeters in diameter. Because it can transform back into a polyp as many times as it needs to, apparently without any kind of degradation or injury, the immortal jellyfish is effectively, well, immortal.

Before you get too excited, though, keep in mind that there’s not a whole lot of research into the immortal jellyfish yet. It’s not even known if they will transform back into polyps in the wild, since it’s only ever been observed in captivity.

Almost all jellies have stinging cells, usually concentrated on the tentacles or oral arms, which they use to stun and kill prey. The stinging cells contain venom-filled nematocysts, which are coiled structures that uncoil and sting when touched. Humans are not jelly prey, but jelly stings can still be uncomfortable—and sometimes fatal—to humans.

You’ve probably heard of the infamous box jellyfish, the most dangerous species of which is common around Australia. Unlike most jellies, box jellyfish have true eyes and a relatively well-developed nervous system. They’re active, hard for humans to detect while swimming since they’re nearly transparent, and in the case of Chironex fleckeri, their venom can kill a human in as little as two minutes. Most fatalities occur in children, but most stings don’t result in death.

Another vicious and occasionally fatal stinger is the Portuguese man o’war, although it isn’t actually a jelly. It’s not even a single animal, it’s a colony. One member is the float, another the feeding polyps, and so forth. The man o’war takes its name from a type of ship, which the float somewhat resembles. The float is bluish or purplish, generally under a foot long [30 cm], and filled with gas. Underneath the float are feeding polyps from which hang purple tentacles, typically around 30 feet long [9 m] but sometimes up to 200 feet long [61 m]. If something attacks the man o’war, it can vent some of the gas in its bladder and submerge temporarily.

When I was a kid, my family occasionally went to the beach in North Carolina. Man o’wars are tropical animals but they do occasionally drift farther north. I was fully aware of this as a kid and did not want to get in the water farther than my waist. My grandfather and one of my aunts reassured me that they’d both been stung by a man o’war once, and it wasn’t any more painful than a wasp sting.

That did not make me feel any better. In fact, it made me even more scared because then I KNEW there were man o’wars out there. I wasn’t afraid of being stung, I was afraid of touching those creepy tentacles.

As it happens, my grandfather and Aunt Barbara probably had not encountered a Portuguese man o’war but a smaller animal called a by-the-wind sailor, which is now my favorite name of anything. It has a blue bladder float like the man o’war, but its sting is much milder, A man o’war sting is incredibly painful, more of a shock, that can lead to intense muscle and joint pain, open wounds on the skin at the sting site, headache, chills and fever, nausea, and can cause victims to faint and drown. Occasionally the venom travels to the lymph nodes and causes even more serious symptoms, including swelling of the larynx, an inability to breathe, and cardiac distress. Even a dead man o’war can sting if you touch its tentacles. Why would you touch its tentacles.

I’m not the only one who feels this way about man o’wars, clearly, because one of its other names if the floating terror. That sounds like the title of a pulp science fiction novel.

The bluebottle is a smaller related species found in the Indian and Pacific Oceans. The man o’war is found in those oceans and the Atlantic. A few weeks ago, in early May 2017, hundreds of man o’wars washed ashore in Georgia and South Carolina. Man o’wars are pretty common around Florida, especially in winter, and occasionally they wash ashore in the thousands.

The man o’war eats fish and other organisms that get caught in the stinging tentacles, but there are some fish that live among the tentacles, even feeding on them, like the man o’war fish and the clownfish. Not a lot of things eat Portuguese man o’wars, but the loggerhead turtle and ocean sunfish do. I like them both. The blanket octopus is immune to the man o’war’s venom and may carry broken-off tentacles to deter predators.

If you’re stung by a man o’war, treat the sting the same way you’d treat other jelly stings. Rinse with vinegar to remove any remaining bits of tentacle or nematocysts, then apply heat for 45 minutes, either with a hot pack or by immersing in hot water. Don’t rinse with urine or vodka; it can make the stings worse—and definitely don’t rinse with fresh water. If you don’t have vinegar, rinse with sea water, but keep in mind that you may be pouring nematocysts back onto the patient with the water. This treatment is from a very recent study conducted by researchers at the University of Hawaii at Manoa, released only a few weeks ago as this episode goes live, so if you’ve heard differing advice for jelly stings, it may be out of date.

Jellies are related to some surprising things: coral, sea anemones, a rare parasitic worm, the freshwater hydra—a ten mm long tubular animal with stinging tentacles at one end that it can stretch four or five times the length of the body to catch its tiny prey. Like jellies, the hydra can regenerate parts of its body if they’re injured or bitten off. And the hydra doesn’t appear to age, making it biologically immortal, although in a different way than the immortal jellyfish.

So what’s the largest jelly known, not counting ridiculously long tentacles like the man o’war’s? That would be the lion’s mane jellyfish. Its bell can have a diameter of over seven feet [2 m] and it has pretty darn long tentacles, too—sometimes over 120 feet long [36.5 m]. It likes cold water and the biggest individuals live where it’s coldest. While small individuals are brown or tan in color, the big ones are usually red or purple. The sting of a lion’s mane jellyfish isn’t usually that bad, but it has a lot of tentacles, so it can inflict thousands of stings upon contact.

In 1973, the Australian ship Kuranda collided with a huge jelly in the South Pacific while traveling through a storm on her way to the Fiji Islands. The jelly was so enormous that the deck was covered in jellyfish goo and tentacles up to two feet deep [61 cm]. One crew member died after getting stung. The weight of the jelly was so great, an estimated 20 tons [18 metric tons] that it started to push the ship nose-down and the captain, Langley Smith, sent out an SOS. The salvage tug Hercules arrived and sprayed the Kuranda’s deck with a high-pressure hose, dislodging the jelly. Samples were sent to Sydney and tentatively identified as a lion’s mane jelly.

But remember, lion’s mane jellies don’t live in the warm waters near Fiji and Australia. There are other reports of lion’s mane jellies seen in the area, though, so it’s possible there’s a gargantuan warm-water variety that hasn’t been discovered yet.

Most jellies live near the surface of the ocean, but there are some deep-sea species known, with more being discovered every year. A gorgeous jelly, dubbed the cosmic jellyfish by the press, was spotted 9,800 feet [2987 m] below the surface near American Samoa this February. It has an umbrella-like bell with short tentacles that point both downward and upward. You may have seen it in the news described as looking like a flying saucer, which it does. A similar jelly was discovered in the Mariana Trench in 2016, almost two and a half miles underwater [4 km]. These are lovely jellies with translucent bells and glowing red and yellow innards, but there are less lovely ones down there.

The big red jellyfish discovered in 2002 is an ugly cuss. It lives in waters up to 4900 feet deep [1493 m] and is over a foot in diameter [30 cm]. It’s dull red in color and doesn’t have tentacles, just thick oral arms.

Stygiomedusa gigantea, also known as the guardian of the underworld by at least one website, and now by me, isn’t so much ugly as horrifying. Its bell is some three feet across [1 m], and while it doesn’t have tentacles or even stinging cells, it does have four 30-foot-long [9 m] oral arms that resemble dark brown or reddish strips of cloth that drift in the ocean currents.

Some deep-sea jellies don’t have tentacles or oral arms. Deepstaria enigmatica, a rare jelly described in 1967, basically just looks like a big mesh bag. Its close relative, Deepstaria reticulum, is very similar, but it’s reddish instead of whitish. The Deepstaria hangs motionless in the deep with its three-foot-wide [1 m] bell open, waiting for something to swim into it. When it does, the bell contracts like a bag, the fish or other organism is stung by nematocysts lining the bell, and the jelly pushes its stunned prey into its mouth with tiny cilia inside the bell.

Isopods, which are small crustaceans, frequently hitch rides inside Deepstaria bells. It’s not known if they’re parasites or confer some benefits to the jellies, but they don’t seem to be affected by the stings.

There are plenty of mysteries associated with enormous jellies, although the two most famous ones I dug into started to seem less and less likely once I got closer to the primary sources. According to Eric Frank Russell in his 1957 book Great World Mysteries, in 1953 a diver testing a new type of deep-sea diving suit in the South Pacific saw an enormous jelly-like monster kill a shark. The diver had been testing how deep he could dive in the suit and noticed a fifteen-foot [4.6 m] shark following him down. I’m going to quote the relevant section instead of paraphrasing, because it’s pretty amazing.

“The shark was still hanging around some 30 feet [9 m] from me and about 20 feet [6 m] higher, when I reached a ledge below which was a great black chasm of enormous depth. It being dangerous to venture farther, I stood looking into the chasm while the shark waited for my next move. Suddenly the water became distinctly colder. While the temperature continued to drop with surprising rapidity, I saw a black mass rising from the darkness of the chasm. It floated upwards very slowly. As at last light reached it I could see that it was of a dull brown color and tremendous size, a flat ragged-edged thing about one acre in extent. It pulsated sluggishly and I knew that it was alive despite its lack of visible limbs or eyes. Still pulsating, this frightful vision floated past my level, by which time the coldness had become most intense. The shark now hung completely motionless, paralyzed either by cold or fear. While I watched fascinated, the enormous brown thing reached the shark, contacted it with its upper surface. The shark gave a convulsive shiver and was drawn unresisting into the substance of the monster. I stood perfectly still, not daring to move while the brown thing sank back into the chasm as slowly as it had emerged. Darkness swallowed it and the water started to regain some warmth.”

I am skeptical, I admit. Eric Frank Russell was primarily a science fiction writer and this sounds like something from a novel, probably one called The Floating Terror. If he described the monster as 20 feet across or even 30 or 40 [6, 9, 12 m], I’d be going, “Hmm, but hey, the deep sea is full of amazing things.” But an acre? That’s 208 feet 9 inches across. 43,450 square feet. A lot of meters [4,046 square meters]. It’s three times the size of my yard, which takes me like an hour to mow. It’s just too big to believe, not without corroborating details—like a first-hand account of the actual diver. We don’t even know his name. And what about the diver’s buddy? Divers don’t go down alone, although maybe they did back in 1953. The whole story is just too thin, too fantastical to be believed.

The other promising mystery I looked into is a supposed legend from Chile, a sea monster that resembles a cow hide stretched flat but with eyes all around the edges and four big eyes in the middle. It rises to the ocean’s surface and swallows animals it encounters.

At first glance this sounds ridiculous, until you realize that many jellies have semi- or fully transparent bells and their internal organs, such as they are, may resemble eye-like blobs in the center of their bodies. Some jellies do have light-sensitive eye spots near their edges too. But the research I did to follow up this story, which I took from Karl Shuker’s blog, but which is originally from Jorge Luis Borges’ 1969 book called The Book of Imaginary Beings, indicated that the actual legend is much different and much less jelly-like.

El Cuero is a cowhide monster called Threquelhuecuvu among the Mapuche of Patagonia. It lives in rivers, lakes, and the ocean. It’s nearly circular, has claws around its edges, and one pair of red eyes. It also has tentacles on its head and a mouth in its middle, which it uses to suck bodily fluids from its prey. It’s supposed to come out of the water and come on land, and when an animal steps on it, it wraps its body around the animal and suffocates it. Then it drags its prey into the water to eat it. The only way to kill it is to throw cacti into the water. When the monster grabs the cacti, it’s pierced through with spines and dies.

It’s generally supposed that the monster is based on freshwater stingrays, although they’re not known to live in Patagonia. But in 1976, after a bus full of tourists ended up on the bottom of Lake Moreno, divers who retrieved the drowned victims reported enormous rays in the depths.

There is a freshwater stingray species in South America which has thorn-like denticles on its body and a closely related species, also with denticles, sometimes travels upriver from the ocean off the Chilean Patagonian coast. That might be the source of the cowhide monster.

So those two mysteries are almost certainly bust. But don’t feel discouraged. Not only was that 20-ton ship-sinking 1973 lion’s mane jelly a real, documented thing that happened [note from episode 248: sorry, it turns out it wasn’t real], there are lots of jelly species being discovered all the time.

Not all are deep-sea species. In 2013, a fisherman in northeast Italy hauled up a net full of golden jellies he’d never seen before. He contacted the local university, and a researcher came out and determined that the lovely golden jellies were completely unknown to science. In 2015, a 9-year-old boy caught a new species of box jelly that’s only around an inch long [3 cm].

There are freshwater jellies too, but not a lot is known about them. To add to the confusing and complex life cycle of marine jellies, many freshwater jellies also have a dormant stage where they basically turn into tiny jelly seeds, tough and capable of surviving even if dried out.

And back in the Cambrian era, some 500 million years ago, some jellies actually had skeletons. Fossil impressions show plates, spines, and spokes from comb jellies, which today are completely soft-bodied. Comb jellies are different from the kind of jellies I’ve mostly talked about in this episode, and not even closely related to them. I’d dig into them next, but we’re already pushing 20 minutes and there’s a limit to how much jellyfish information I can expect my listeners to tolerate in one sitting. We’ll save the comb jellies for another episode.

You can find Strange Animals Podcast online at That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 015: Hammerhead shark and Megalodon!

This week’s episode is all about some awesome sharks: the hammerhead shark, which used to scare the poop out of me when I was a kid, and the unbelievably huge but fortunately for all the whales extinct megalodon! Thanks to Zenger from Zeng This! for recommending such a great topic!

The great hammerhead, a huge and freaky-looking shark.

A ray leaping out of the water to escape a hammerhead. The article I pulled this from is here.

A guy with a teeny adorable bonnethead, a newly discovered species of hammerhead.

Hello there. I am a great white shark.

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week’s episode was suggested by Zenger from the fun pop culture podcast Zeng This!, which I recommend if you don’t already subscribe. He suggested megalodon as a topic, so since I was already researching hammerhead sharks, I decided to put together a shark episode.

We’ll start with the hammerhead shark, because hammerheads scared the crap out of me as a kid. They just look so weird! You know what else scared me as a kid? Skeletons. It’s a good thing no one ever showed me the skeleton of a hammerhead shark.

There are a lot of species of hammerhead shark, some of them small like the new species of bonnethead discovered earlier this year that’s only about as long as your forearm, and some of them huge, like the great hammerhead, which can grow up to 20 feet long [6 meters]. One of the biggest sharks ever caught was a great hammerhead. At fourteen feet long [4.2 meters], it wasn’t the longest shark ever, but it weighed 1,280 pounds [580 kg]. It was caught in 2006 off the coast of Florida.

If it weren’t for its weird head shape, the hammerhead wouldn’t seem all that interesting. It’s mostly plain gray in color, hardly ever attack humans, and is common all over the world. But they’ve got that head! The shape is called cephalofoil, and not only are the shark’s eyes on the end of the stalks, the head is flattened.

Researchers think the shape serves two purposes. A hammerhead shark can see really well since its eyes are so far apart, and the shape actually provides a certain amount of lift when water flows over it, like an airplane’s wing, which helps the shark maneuver. Plus, of course, a wide head allows for even more electroreceptor cells so the shark can sense prey better.

Hammerheads have relatively small mouths compared to many other sharks. They do a lot of feeding on the ocean floor, snapping up rays, fish, crustaceans, octopus, even other sharks. Oh yeah, and a hammerhead will actually use its head as a weapon. Hammerheads like eating stingrays and will pin one to the ocean floor with its head to keep it from escaping until the shark can bite it. In February of 2017, tourists surfing near Panama saw a spotted eagle ray escape a hammerhead shark by leaping out of the water like a bird. The stingray actually beached itself on an island, too far up the beach for the shark to reach. After it gave up, the ray managed to catch a wave that carried it back out to sea. That’s pretty epic.

Hammerhead sharks are considered a delicacy in many countries, but since their fins are the most valuable part of the fish, fishermen sometimes catch a shark, cut its fins off, and toss the still-living shark back in the ocean. It always dies, because it can’t swim without fins. The practice is horrific and banned in many countries. Overfishing has also threatened many hammerhead species. Researchers estimate that the great hammerhead in particular has decreased in numbers some 80% in the last 25 years.

Ironically, recent studies have found repeatedly that shark fins and meat contain high levels of mercury and a neurotoxin called BMAA, which is linked to neurodegenerative diseases in humans. The frequent eating of shark fin soup and other dishes made of shark meat, and cartilage pills which some people take as a diet supplement, may increase the risk of developing diseases like Alzheimer’s and Lou Gehrig’s disease. (I ate shark once, a shark steak. It was terrible.)

You may think a 20-foot hammerhead is a really big shark, and it is. Great white sharks aren’t much bigger. But before the great white and the hammerhead, a 60 foot [18 meter] shark ruled the oceans. Megalodon is first found in the fossil record around 23 million years ago, and died out about 2 ½ million years ago. Because shark skeletons are made of cartilage instead of bone, they don’t fossilize well. We have a whole lot of megalodon teeth, but except for some vertebrae we don’t know much about the rest of the shark.

Researchers generally compare megalodon with the great white, since while they’re not necessarily closely related, they occupy the same ecological niche. We do know how the teeth were arranged, since associated teeth in formation as they had been in the jaw, although the jaw itself wasn’t preserved, have been discovered in North Carolina and Japan.

At a rough estimate, megalodon probably grew 60 or even 70 feet long [18 to 21 m]. Its jaws were over six feet across [1.8 meters] with some 276 teeth in five rows. Due to the size of its teeth and jaws, it probably mostly preyed on large whales, and was probably a lot blockier looking than the great white. If the great white is a racecar, megalodon was that bus from Speed.

Some researchers want to classify megalodon as a close relative of the great white shark, which has serrated teeth like megalodon’s. But others argue the great white is more closely related to the mako shark, which does not have serrated teeth. For a long time the megalodon hypothesis was more accepted, but a study published in the March 12, 2009 issue of Journal of Vertebrate Paleontology concluded that mako sharks and great whites probably share a recently discovered fossilized ancestor some 4 to 5 million years old. Its teeth have coarse serrations, which researchers think are a transitional point between no serrations and the serrations in modern great white shark teeth. The similarities between the great white and megalodon are due to convergent evolution.

This points to something many people don’t understand about science. It’s messy. It’s incomplete. Our collective body of knowledge is being added to, adjusted, reinterpreted, and hopefully corrected all the time. From the outside it can look like people arguing over ridiculous minutiae, or a bunch of eggheads who can’t make up their minds. In reality, as new information is added to what we know, what we used to think was true has to be changed to fit new facts. It’s exciting!

For a long time researchers though megalodon died out around the beginning of the Pleistocene because the world grew colder as the world entered into the ice ages. New findings suggest that climate change didn’t push the megalodon into extinction, other sharks did. Newcomers like the great white and the orca, which of course isn’t a shark but a whale, starting expanding into new territory, out-competing megalodon around the same time that a lot of marine mammals were also going extinct. Megalodon needed a lot of food to survive—more than the much smaller upstarts.

Back when megalodon was king, though, there was plenty of food to go around. It wasn’t even the only mega-predator hunting the oceans. In 2008, fossils of an ancestor of today’s sperm whale were discovered in Miocene beds dated to around 12 or 13 million years ago. The whale has been dubbed Livyatan melvillei and estimates of its length, from the partial skull, lower jaw, and teeth that were found is around 57 feet [17 meters]. Since modern sperm whales are frequently some 60 feet long [18 m] and 80-foot [24 m] monster males were reported in the past, it’s possible the newly discovered Leviathan could attain similar lengths. Its biggest teeth were two feet long [61 cm] compared to modern sperm whales’ 8-inch teeth [20.5 cm]. It also apparently had teeth in its upper jaw as well as its lower. The sperm whale only has teeth in its lower jaw, and since it mostly eats squid, it doesn’t really need teeth at all. Individuals who have lost their teeth survive just fine.

The Leviathan, though, used its teeth. Like megalodon, it may have preyed on baleen whales. Megalodon teeth were found in the same fossil deposits where the Leviathan was discovered. I bet they battled sometimes.

So how do we know Megalodon isn’t still around, cruising the oceans in search of whales? After all the megamouth shark was only discovered in 1976 and it’s almost 20 feet long [6 m]. Well, we have two big clues that there isn’t a population of Megalodon sharks still living. Both involve its teeth.

Sharks have a lot of teeth, and they lose them all the time as new teeth grow in. Shark teeth are among the most common fossils around, and any dedicated beachcomber can find shark teeth washed up on shore. If megalodon still lived, we’d be finding its teeth. We’d also probably be finding whales and other large marine animals with scars from shark attacks, the way we find scars on sperm whales from giant squid suckers.

Wait, you may be saying, no one was talking about megamouth shark teeth found on beaches before it was discovered. Well, megamouth sharks have tiny, tiny teeth that they don’t even use. They gather food with gill rakes that filter krill from the water. Megalodon teeth can be seven inches long [18 cm]. Great white teeth are only two inches long [5 cm]. Occasionally a fossilized megalodon tooth washes up on shore, and when it does, it makes the news.

So okay, you might be saying, you fractious person you, what if megalodon survived into modern times but has died out now. Well, we’d probably still know. Not only would the non-fossilized teeth still be found, since nothing is going to eat them and they don’t decay readily, but a lot of cultures have incorporated shark teeth into weapons over the centuries. A seven-inch serrated tooth is a weapon worth having.

Consider the Gilbert Islands in the Pacific. Sharks were important in the Kiribati culture there, and the people crafted amazing weapons with shark teeth. Anthropologists studying the weapons discovered that some of the teeth used in older weapons come from sharks that are now extinct in the area.

So no, I’m going to insist that whatever you saw on Shark Week, megalodon is not out there and hasn’t been for a couple of million years. But what about other mystery sharks?

There aren’t very many reports, surprisingly. Even Karl Shuker comes up empty, with just one mention of a reportedly hundred-foot [30 m] shark called the Lord of the Deep by Polynesian fishermen, but I can’t find any additional information about it.

That doesn’t mean there aren’t mystery sharks out there, of course, just that they’re probably not gigantic or radically different from known shark species. In fact, new sharks are discovered all the time. In just the last few months, a three-foot [1 m] ghost shark with rabbit-like teeth, and a tiny hammerhead called a bonnethead have been described. And yeah, I’d love to be wrong about the megalodon’s existence.

Researchers are studying the genetics of sharks’ rapid healing, which could have important medical applications for humans. A recent study published in the January 2017 BMC Genomics Journal provides evidence that the genes linked to the immune system in sharks and rays have evolved in ways that their counterparts in humans have not. One gene is involved in killing cells after a certain amount of time, which is something cancer cells manage to avoid. It’s possible that as researchers learn more, new therapies for treating cancer in humans could be developed.

So maybe we should stop eating so many sharks. Shark meat isn’t good for you anyway.

You can find Strange Animals Podcast online at That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at We also have a Patreon at if you’d like to support us and get twice-monthly bonus episodes for as little as one dollar a month.

Thanks for listening!

Episode 011: The Vampire Squid and the Vampire Bat

This week we’re going all goth in April for the vampire squid and the vampire bat. They’re so awesome I want to die.

The vampire squid looking all menacing even though it’s barely a foot long.

“I love you, vampire bat!!” “I love you too, Kate.”

Thanks for listening! We now have a Patreon if you’d like to subscribe! Rewards include patron-only episodes and stickers!

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

I thought about waiting to run this episode in October, but that’s a really long way away. So we’ll have Halloween in April and talk about the vampire squid and the vampire bat.

The vampire squid has one of the coolest Latin names going, Vampyroteuthis infernalis, which means “vampire squid from hell.” It’s a deep-sea squid and until recently, not a lot was known about it. It was discovered in 1903 and originally classified as an octopus. Its body is about six inches long [15 cm], with another six inches or so of tentacles, which are connected with webbing called a cloak. Actually I’m not sure if scientists refer to this as a cloak, but if you’ve called your animal the vampire squid from hell, you can’t complain if podcasters, for instance, refer to web-connected octopus legs as a cloak.

So is it an octopus or a squid? It’s both, in a way. The vampire squid is the last surviving member of its own order, Vampyromorphida, which shares similarities with both.

The vampire squid’s color varies from deep red to velvety black. The inside of its cloak is black and the parts of its legs inside the cloak are studded with spines. Its beak is white. Basically the only thing this little guy needs to be the world’s ultimate goth is a collection of Morrissey albums.

It lives in the lightless depths of the ocean below 3,000 feet [914 meters]. There’s not a lot of oxygen down there so there aren’t very many predators. The vampire squid doesn’t need oxygen because it’s a vampire—or at least it can live and breathe just fine with oxygen saturations as little as 3%. Its metabolic rate is the lowest of any cephalopod.

The vampire squid doesn’t move a lot. It drifts gently, aided in buoyance because its gelatinous tissues are roughly the same density as seawater. Adults have two small fins sticking out from their mantle, which they flap to propel them through the water.

If something threatens a vampire squid, it brings its legs up to expose the spiny insides of its cloak and hide its body. If something really threatens a vampire squid, even though it doesn’t have ink sacs, it can eject a cloud of bioluminescent mucus, and can flash its photophores in a dazzling display of lights. These photophores are concentrated on the outside tips of its arms. If the end of an arm is bitten off, the vampire squid can regenerate it.

So we have a creepy-looking, if small, cephalopod that lives in the deep, deep sea called a vampire squid. WHAT. DOES. IT. EAT?

I hate to disappoint you, but the vampire squid eats crap. In fact, it eats the crap of animals that eat crap. There’s not a lot of food in the ocean depths. Mostly there’s just a constant rain of fish poop, algae, bits of scales and jellyfish, and other waste. Lots of little creatures live on this stuff and their poop joins the rain of barely-food that makes it down to the abyssal depths where the vampire squid waits.

The squid had two retractable filaments—not the same thing as the two feeding tentacles true squids have, but used for feeding. The filaments are extremely long, much longer than the vampire squid itself. It extends the filaments, organic detritus falls from above and sticks to them, and the vampire squid rolls the detritus up with mucus from its arm tentacles into little sticky balls and pops the balls into its mouth.

That’s not very goth. Or it might be incredibly goth, actually.

Most cephalopods only spawn once before they die. A 2015 paper in Current Biology reports that the vampire squid appears to go through multiple spawning phases throughout its life. It may live for a long time too, but we don’t know for sure. There’s still a lot we don’t know about the vampire squid.

Because squids and octopuses are soft bodied, we rarely find them in the fossil record. In 1982, though, a beautifully preserved octopus body impression was found in France in rocks dating to 165 million years ago. And guess what kind of octopus it turned out to be! Yes, it’s related to the vampire squid.

If the vampire squid is the kind of pensive goth who listens to The Smiths and reads Poe in cemeteries, the vampire bat is out clubbing with its friends, blasting Combichrist, and spending its allowance in thrift shops. There are three species of vampire bat, but they’re different enough from each other that each belongs to its own genus. They’re native to the Americas, especially tropical and subtropical environments, although they haven’t been found any further north than Mexico. And yes, vampire bats do actually feed on blood. It’s all they eat.

Vampire bats are small, active, and lightweight. They’re only about 3 ½ inches long [9cm] with a 7-inch wingspan [18 cm], and weigh less than two ounces [57 grams]. They live in colonies that consist of big family groups: a small number of males and many more females and their babies. Males without a colony hang out together and probably never clean up their apartments.

Vampire bats belong to the leaf-nosed bat family, and like other leaf-nosed bats they sleep during the day and hunt at night. But the vampire bat doesn’t actually have a nose leaf. That’s a structure that aids with echolocation, and vampire bats don’t need the high level echolocation ability that insect-eating bats do. They get by with a reduced ability to echolocate, but they have another highly developed sense that no other mammal has: thermoreception. They use it to determine the best place to bite their prey. The warmer, the better. That’s where the blood is.

The vampire bat also has good eyesight, a good sense of smell, and hearing that’s attuned to the sound of breathing. A bat frequently remembers the sound of an individual animal’s breathing, and returns to it to feed night after night. What vampire bats don’t have is a very good sense of taste. They don’t really need it. In fact, they don’t have the kind of bad food avoidance that every other mammal has. In a study where vampire bats were given blood with a compound that tasted bad and made them throw up, the next time they were offered the bad-tasting blood, they ate it anyway.

Most bats are clumsy on the ground. They’re built for flying and for hanging from perches. But vampire bats are agile. They crawl around and even run and jump with no problems.

Two species of vampire bat prey mainly on birds, while the third—the common vampire bat—feeds on mammals. Bird blood has a much higher fat content than mammal blood, which is higher in protein. But results of a study released in January 2017 found that hairy-legged vampire bats, which usually prey on large wild birds, had started feeding on domestic chickens as their wild prey became scarcer—and then they started feeding on human blood.

A vampire bat doesn’t suck blood. It makes a small incision with extremely sharp fangs and laps up the blood with its grooved tongue. It may even trim hair from the bite site first with its teeth. Its saliva contains an anti-coagulate called draculin that keeps the blood flowing. The bat doesn’t eat much, because let’s face it, it’s just a little guy. In order to hold more blood, as soon as it starts to feed its digestion goes into overdrive. Within some two minutes after it starts to eat, the bat is ready to urinate in order to get rid of the extra fluid so it can hold more blood. A feeding session may last about 20 minutes if the bat isn’t disturbed, and the bat may drink about an ounce of blood in all.

A vampire bat needs to eat at least every two days or it will starve. A bat that hasn’t found prey in two nights will beg for food from its colony mates, which often regurgitate a little blood for the hungry bat to eat. New mother bats may be fed this way by her colony for as much as two weeks after she’s given birth so that she doesn’t have to hunt. Baby vampire bats drink their mother’s milk just like any other mammal.

If a mother bat doesn’t return from hunting, other colony members will take care of her baby so it won’t die. Colony members groom each other and are generally very social. Even the male bats that aren’t part of the colony are allowed to roost nearby. Nobody fights over territory. These are nice little guys.

Vampire bats do sometimes carry rabies, but it’s pretty rare compared to infection rates in dogs. They are more dangerous to livestock than to humans. Attempts to kill off vampire bat colonies to stop the spread of rabies actually has the opposite effect, since bats from a disturbed colony will seek out another colony to join.

Vampire bats have considerable resistance to rabies and frequently recover from the disease, after which they’re immune to reinfection, and there’s some preliminary evidence to suggest that native human populations in areas where vampire bats are common may also have developed some resistance to rabies. Researchers hope that this finding will lead to better treatment of rabies in the same way that the draculin anticoagulant in vampire bat saliva led to advances in blood-thinning medications.

I like to imagine a vampire bat hanging out with a vampire squid. The bat would sip blood from a tiny wineglass and fidget with its jewelry while it tries to conversation. The squid would just stare at the bat. Then it would eat a globule of crap. The bat would pee on itself and the whole evening would just be a bust. Also, one of them would drown but if I can imagine a tiny wineglass I can imagine a tiny bat-sized bathysphere or something. Never mind.

You can find Strange Animals Podcast online at That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at We also have a Patreon at if you’d like to support us and get twice-monthly bonus episodes for as little as one dollar a month.

Thanks for listening!

Episode 006: Sea Monsters

This week’s episode is all about sea monsters: mysterious sightings, possible solutions, and definitely discovered monsters of the world’s oceans!

The giant oarfish! Try to convince me that’s not a sea serpent, I dare you.

The megamouth shark. Watch out, krill and jellyfish!

The frilled shark. Watch out, everything else including other sharks!

A giant isopod. Why are you touching it? Stop touching it!

Sorry, it’s just a rotting basking shark:

Recommended reading:

In the Wake of Bernard Heuvelmans by Michael A. Woodley

In the Wake of the Sea-Serpents by Bernard Heuvelmans

The Search for the Last Undiscovered Animals by Karl P.N. Shuker

Episode 003: The Tuatara and the Sea Lamprey

In this week’s episode, we look at a couple of so-called living fossils: the tuatara and the lamprey. One of them hasn’t changed appreciably in almost 400 million years. Tune in to find out which one and learn about how gross it is and how cute the other one is! (I may be biased.) (re-recorded audio)

The adorable tuatara! It eats anything, including baby tuataras. Not cool, lizardy guy:

A face not even a mother could love. The sea lamprey:

A recently discovered fossil lamprey, complete with impression of its body:

Show transcript:

Welcome to Strange Animals Podcast. I’m your host, Kate Shaw.

This week’s episode is about my favorite reptile and a revolting sea creature, and just to be clear, those are two different animals.

If you look at a tuatara, it appears pretty ordinary. It’s a brownish-grayish-green lizard with lighter-colored spines along its back, and it can grow to about two feet long, or 61 cm. It’s a hefty lizard, sure, but you’d probably think it was nothing special. But dang, is it special.

First of all, it’s not strictly a lizard. It’s the only surviving member of its own order, Rhynchocephalia. It also has many physical traits not shared by lizards—or any other living reptile. Or mammal. Or bird. Or anything else.

Its teeth, for instance. The tuatara has two rows of teeth in the upper jaw, one in the lower, with the lower jaw’s teeth fitting neatly between the two upper rows. Some snakes have two upper rows of teeth and one lower row, but not arranged like the tuatara’s. Not to mention that the tuatara’s teeth aren’t even teeth at all. They’re just pointy projections of the jaw bone.

The tuatara also chews in a literally unique way. When the lower teeth mesh between the upper rows of teeth, the animal moves its jaw forward and back. This slices its food against the sharp tooth edges.

The tuatara also has a third eye. I’m not making this up. It legit has a photoreceptor on top of its head called the parietal (pahRAYetal) eye with a lens, cornea, retina, and so forth. Hatchling tuataras have a translucent patch of skin above the eye, but as the hatchling grows and molts its skin, the patch darkens until the third eye is no longer visible. Researchers think it may help with thermoregulation and hormone production. The tuatara isn’t the only creature with a third eye, but it has the most well developed one.

Like the turtle, the tuatara has a primitive auditory system. It has no external ears and no eardrum, although it can hear. Its skeleton has some features apparently retained from its fish ancestry, such as its spine and some aspects of its ribs. Males don’t have a penis—but a lot of birds don’t either and we still have lots of birds, so obviously they make it work.

Because it has such a slow metabolism—the lowest body temperature of any other reptile—the tuatara grows slowly. It won’t reach breeding age until it’s ten to twenty years old, and females only lay eggs about once every four years. The average lifespan of a tuatara is 60 years. Researchers believe it could live to 200 years in captivity.

Baby tuataras are active in the daytime, probably so their parents won’t eat them. Tuataras eat pretty much anything they can catch. Adult tuataras are active at night, and sleep during the day in dens. Sometimes a tuatara digs its own den, sometimes it shares a den with burrowing seabirds. The birds leave in the morning and the tuatara comes home to sleep until night, when the birds return.

The Tuatara is native to New Zealand, and in an all-too-common situation, when people showed up, the tuatara promptly went extinct on the mainland. It was restricted to 35 islands where it was mostly safe from introduced rats, until its reintroduction in the fenced Karori Sanctuary in 2005. Tuataras have begun to breed in the sanctuary.

One thing I didn’t know about New Zealand—one of many many things, since pretty much all of my New Zealand knowledge comes from watching the Lord of the Rings movies, is that it was underwater for millions of years. Some 82 million years ago, New Zealand separated from Gondwana, the chunk of land that eventually separated into the southern continents we know today. The entire continent containing New Zealand was partially drowned some 25 million years ago, and for a long time scientists thought New Zealand was completely underwater. In the late 2000s, though, a fossil tuatara was found in New Zealand that was dated to about 18 million years ago. If New Zealand was underwater for a few million years, how did the tuatara recolonize it after the sea receded? Tuataras are not good swimmers, and it’s a long distance to float on driftwood without water.

Researchers now think that the highest elevations of New Zealand remained above sea level, allowing tuataras and some other species of plants and animals to survive the inundation.

You’ll see the tuatara referred to as a living fossil in a lot of articles. The media loves to call things living fossils. The tuatara has been around for 225 million years, but so have crocodiles and alligators. In fact, crocs and gators are found in the fossil record even earlier, 250 million years ago. The tuatara in particular has a lot of modern adaptations, including a number of cold-weather adaptations. A 2008 study discovered that the tuatara has the highest molecular evolution rate of any animal ever measured.

Basically, you can’t keep the tuatara down. Drown its entire continent? No problem. Run a couple of ice ages through there? It’ll adapt. And now we realize that this isn’t even its final form.

I take you now from a chunky little lizardy thing eating crickets in New Zealand to a two-foot-long monstrosity that drills into living creatures to drink the blood and bodily fluids it rasps from their tissues, the sea lamprey.

What does the tuatara have to do with the sea lamprey? I mean beyond the fact that the tuatara would happily slurp up any lampreys it could get into its mouth? Well, if the tuatara is the most rapidly evolving creature ever studied, the lamprey has remained basically unchanged for at least 360 million years.

Lampreys are eel-like parasites that lack jaws. Instead, they have a circular mouth rimmed with rows and rows of rasping teeth, for lack of a better word. I saw this described in one paper as a feeding apparatus, and it’s as good a description as any although it doesn’t convey the utter, utter horror that is the lamprey’s mouth. I may be showing my prejudices here.

Those aren’t teeth, by the way, they’re made of cartilage. The lamprey doesn’t have any bones at all, but it does have a cartilage tooth-studded tongue used to drill into its prey once it’s clamped on with its sucker-like mouth. Dear God.

Not all lampreys are parasitic. Some are filter feeders as larva and don’t eat at all once they grow up, just live on their bodily reserves until they breed and die, but I’m just talking about parasitic lampreys today because they’re gross. The most common parasitic lamprey is the sea lamprey, which lives in the Atlantic Ocean, parts of the Mediterranean and Black Seas, and in the Great Lakes as an introduced pest. The sea lamprey can grow up to four feet long, or 120 cm.

Because of their lack of bone, lampreys don’t fossilize well, but one fossil found in South Africa has revealed a lot about the lamprey. In a 2006 paper in Nature, researchers describe a beautifully preserved lamprey dated to 360 million years ago. Not only are the gills and mouth perfectly visible, so is an impression of its body. It was the oldest lamprey fossil found at the time, and it shows that the lamprey basically hasn’t changed ever since. If anything deserves to be called a living fossil, it’s the lamprey.

Back when the lamprey first evolved, it wasn’t preying on true fish. There weren’t any yet. The lamprey has held fast through at least four major extinction events. It’s a vertebrate, but has never evolved those things other vertebrates—except the hagfish, which is just weird—have developed: jaws, scales, paired fins. On the other hand, some lampreys do have a third eye.

Because lampreys are so primitive from an evolutionary standpoint, scientists can study them to learn how other vertebrates evolved. For instance, the lamprey has seven pairs of gill arches. In other vertebrates, the interior pair of gill arches evolved into upper and lower jaws and middle ear bones. That includes us.

Lampreys today prefer fresh water that’s not too warm, although the sea lamprey spends most of its adult life in the ocean, although it will also be fine in fresh water. The sea lamprey migrates upriver to spawn. After the female lays her eggs, she and the male both die. When the eggs hatch, the larvae migrate downstream to quiet water where they feed on plankton until they metamorphose into adult lampreys. Then they continue their migration downstream to the ocean or lake. They live about a year before returning upstream to spawn and die.

Lamprey larvae live as filter feeders, and until about 2014 scientists didn’t know if this was a recent development or not. Then some fossilized lamprey larvae were discovered in inner Mongolia rocks dating back 125 million years, and they look identical to modern larvae.

Old and “primitive” as it is, the lamprey is able to tolerate all sorts of environments. Most water animals can either live in saltwater or freshwater, not both, but the sea lamprey does just fine in either. In the Great Lakes, sea lampreys are so damaging to the native fish that researchers have been trying for decades to get rid of them. The sea lamprey can also feed on fish that are toxic to pretty much any other predator.

In many cultures, lamprey is considered a delicacy, and it’s supposed to taste quite good, but make sure you clean those things well. Their mucus is a toxin. You will not catch me eating lamprey if I can possibly avoid it.

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Thanks for listening!