Category Archives: sharks

Episode 163: Three Weird Fish

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Thanks to Nathan for his suggestions! This week we’re going to learn about three strange and interesting fish!

A northern snakehead:

A giant snakehead:

A Greenland shark, fish of mystery:

The upside-down catfish is indeed upside down a lot of the time (this is actually a picture of Synodontis nigriventris, closely related to the upside-down catfish we talk about in the episode):

An ancient Egyptian upside-down catfish pendant that ladies wore in their hair:

Show transcript:

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

We haven’t done a fish episode in a while, so this week let’s learn about three weird fish. Thanks to Nathan for suggesting the first two fish, the snakehead and the Greenland shark.

The snakehead is a freshwater fish that gets its name because while it’s an ordinary-looking fish for the most part, it has a flattened head that looks a little bit like a snake’s. Different species of snakehead look different in other ways, of course, so let’s examine a couple of typical species.

The northern snakehead is native to Asia, but it’s been introduced into other parts of the world by accident or as a food fish. It’s one of the largest species, with reports of some specimens growing up to five feet long, or 1.5 meters. It’s usually no more than three feet long, though, or 1 meter. It’s brown with darker blotches and has sharp teeth that it uses to catch fish, frogs, and other small animals.

Like other snakeheads, the northern snakehead can breathe air and survive out of water for several days as long as it stays damp. Young snakeheads can even wriggle considerable distances on land to find water. It likes stagnant or slow-moving water.

Because it’s a fierce predator that can find its way to new waterways, introduced snakeheads are invasive species that can cause havoc to populations of native fish. The northern snakehead has been introduced into many waterways in the United States in the last twenty years, as a result of people releasing unwanted aquarium fish and accidental release of snakeheads in fish-farming operations. Since snakeheads reach mature age quickly and females can lay thousands of eggs at a time, snakeheads are illegal to own in many places now and release snakeheads into the wild is even more against the law.

The giant snakehead also grows up to five feet long, or 1.5 m, and is from parts of southeast Asia. Young giant snakeheads are red, but when they grow up they’re black and white with a thick black stripe down each side. It’s also been introduced into a lot of places as a food fish and a game fish, but since it’s a tropical species it can’t survive colder weather and isn’t as invasive as a result, at least not outside of tropical and subtropical areas.

The giant snakehead can be aggressive, though, especially when it’s guarding its nest. Both parents act as guards of the eggs and the newly hatched babies, which follow their mother around wherever she goes. That’s actually really cute.

Next let’s talk about the Greenland shark. We covered it briefly in episode 74, about colossal squid and the things that eat them, but mostly we talked about its close relative the sleeper shark. The Greenland shark is similar in some ways but it’s much bigger than the sleeper shark. It lives in the North Atlantic and Arctic Oceans where the water is barely warmer than the freezing point and it grows up to 24 feet long, or 7.3 meters, with females being larger than males.

But despite how enormous it is, it’s not a shark you need to worry about. First of all, what are you doing swimming in water that cold? Second, the Greenland shark is a slow swimmer, no more than about 1 ½ miles per hour, or 2.6 km/h. You can walk faster than that without even trying. You can probably dog-paddle faster than that.

And yet, the Greenland shark manages to eat seals and fish and other animals that move quickly. Since no one’s actually observed a Greenland shark hunting, no one knows how they catch prey. Some researchers speculate that it sneaks up on sleeping seals and grabs them. It also eats a lot of carrion, including dead moose and reindeer and polar bears that fall into the water and drown. One shark was found with an entire reindeer in its stomach.

The Greenland shark spends winter in shallow water where it’s warmer, but in summer it spends more time in deep water. At least one submersible observed a Greenland shark 7,200 feet below the surface of the ocean, or 2,200 meters. Occasionally a Greenland shark travels more widely, usually in deep water where the water is cold. In 2013 one was caught by researchers in the Gulf of Mexico, which is way far away from the Arctic. It was swimming at over 5,700 feet deep, or 1,750 meters.

The Greenland shark is adapted to the cold and pressure of the deep sea in many ways. Its blood contains three types of hemoglobin, which help it absorb as much oxygen as possible from water that’s poorly oxygenated to start with. Its muscles and other tissues contain high levels of urea and other compounds that increase its buoyancy, so that it doesn’t need to work as hard to stay in one place. But the presence of urea in its muscles means that the Greenland shark not only tastes horrible, it’s toxic. In Iceland Greenland sharks are considered a delicacy, but only after the toxins have been removed from the meat by long treatment. This includes burying it in the ground for weeks, partially fermenting it, and drying it for several months afterwards. Most people don’t bother and any commercial fishing boats that catch Greenland sharks just toss them back overboard.

The Greenland shark has a very slow metabolism and grows extremely slowly too. That’s okay, though, because it lives a very long time. A VERY long time. The biggest Greenland sharks may be as much as 600 years old. Researchers examine the crystals in dead Greenland shark eyeballs to determine when they were hatched.

And speaking of Greenland shark eyeballs…some of you know where this is going. I hope you’re not eating grapes or anything right now. There’s a type of copepod, a crustacean, that acts as a parasite of the Greenland shark and the Pacific sleeper shark, its close relative. The copepod grows to about an inch long, or 28 mm, and attaches itself to the shark’s cornea, which is part of the eyeball. This impairs the shark’s vision but it doesn’t seem to care and it doesn’t seem to have any trouble finding food.

Okay let’s stop talking about that. Our third and final weird fish for this episode is a type of catfish that’s sometimes kept in aquariums. It’s called the upside-down catfish.

There are actually a number of closely-related catfish known as upside-down catfish, but the one we’ll talk about today is Synodontis batensoda. It lives in parts of Africa in marshy areas and slow-moving water. It grows to a little over a foot and a half long, or 50 cm, and eats plankton, algae, mollusks, insects and larvae, and crustaceans.

But the upside-down catfish gets its name from its habit of swimming upside down. Because it’s kept as an aquarium fish so often, many people assume that the upside-down swimming is something it developed because it’s kept in an enclosed aquarium habitat. But that’s actually not the case.

The catfish used to be well-known in Egypt, and there’s even an Egyptian tomb carving depicting a catfish swimming upside down, dating to the Middle Kingdom around 4,000 years ago. The upside-down catfish was often depicted in jewelry, too, including hair ornaments so beautifully made that the species of catfish can be determined. Young women in Egypt traditionally wore fish ornaments to decorate their braids. There’s a story about one young woman who was helping row a king across a lake when her fish pendant fell into the water. She stopped rowing, naturally, which messed up the other rowers. The king wanted to know why the boat had stopped, and when the woman explained, he offered to give her a new fish pendant. But no, she said, she wanted that one, the one that was now at the bottom of the lake. But the king had a magician who said no problem, and caused the water to fold back like a blanket, exposing the lake’s bottom so the pendant could be retrieved. I didn’t make that story up, either. It’s from the Westcar Papyrus that dates to around the 17th century BCE.

So why does the upside-down catfish swim upside down? Like other catfish, its mouth is angled downward so it can find food in the mud at the bottom of the water. So when it wants to grab an insect on the water’s surface, or eat algae off the bottom of a submerged leaf, it can only do so by turning upside down.

So that’s it for this week’s episode. I don’t know what else to say because I’m just sitting here trying to imagine how I’d manage if someone told me I had to swim upside down. But then, I can barely swim right side up. Good job, upside-down catfish!

You can find Strange Animals Podcast online at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at patreon.com/strangeanimalspodcast 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 153: The White River Monster

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Let’s start out the new year with a bona fide mystery animal, the White River Monster from Arkansas! Is it a real animal? If so, is it a known animal or something new to science? If it’s a known animal, what could it be? Lots of questions, maybe a few answers! Happy new year!

Further listening:

MonsterTalk

The not exactly useful picture supposedly of the White River Monster, taken in 1971:

A northern elephant seal, AKA Mr. Blobby:

A Florida manatee:

A bull shark:

Two bottlenose dolphins:

An alligator gar (below) and a human (above):

Alligator gar WEIRD FISH FACE:

Gulf sturgeon:

Show transcript:

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

If you’ve listened to the final episode of 2019 last week, you’ll remember it was about some mystery water animals of various kinds. Well, I’ve got another water mystery for you today to start off the new year, the White River monster. I heard about this one in a recent episode of MonsterTalk, which is a great podcast I recommend if you don’t already listen to it.

The White River is in North America, originating in the mountains in northwestern Arkansas and flowing from there through Missouri, then back into Arkansas where it joins the Mississippi River. In 1915 a man near the small town of Newport, in the central Ozarks region of Arkansas, saw an enormous animal with gray skin in the river.

A few other people saw it too, but it wasn’t until July of 1937 that things really heated up. The monster returned, and this time a lot of people saw it. News of it hit the local papers and spread throughout the country, and people started showing up to look for it. Some people came prepared to kill or catch it while others just wanted to see it.

Estimates of the monster’s size varied quite a bit. A man named Bramlett Bateman, who owned a lot of the farmland along that stretch of the river, was quoted in several newspaper articles. He described the monster as being the length of three cars in one article, but in another his estimate was smaller, only 12 feet long, or 3.7 m, and four or five feet wide, or 1.2 to 1.5 meters. But it doesn’t seem that he or anyone else got a really good look at it.

It was described by numerous people as being gray-skinned. Bateman said it had “the skin of an elephant…with the face of a catfish.” I dug into as many original newspaper articles as I could find without actually paying for access to them, and very few of them have a real description of the animal. The only description given in a New York Times article from July 23, 1937 is this:

“Half a dozen eye-witnesses…reported seeing a great creature rise to the surface at rare intervals, float silently for a few minutes and then submerge, making its presence known only by occasional snorts that bubbled up from the bottom.”

Another article quotes Bateman as saying he saw the monster “lolling on the surface of the water.”

Bateman decided he was going to blow the monster up with dynamite. What is it about people whose go-to solution to seeing an unidentified animal is to throw dynamite in the water? The local authorities said, uh no, you cannot just throw dynamite into the river, but other people brought machine guns and other weapons and patrolled the river looking for the monster. A plan to make a giant net and catch the monster petered out when people found out that making and deploying a net that big is expensive and difficult.

The monster was mostly reported in an eddy of the river that stretched for about a mile and was unusually deep, about 60 feet deep, or 18 meters. The river is about 75 feet wide at that point, or 23 meters. The Newport Chamber of Commerce hired a diver from Memphis named Charles B. Brown, who brought an eight-foot harpoon with him when he descended into the river. He didn’t find anything, but the tourists had fun.

Suggestions as to what the monster might be ranged from a sunken boat that sometimes bobbed briefly to the surface to a monstrous catfish. Many people were convinced it was a huge fish of some kind, especially an alligator gar.

Eventually sightings tapered off and the excitement died down until June of 1971, when it started being seen again. Again the size estimates were all over the place, with one witness saying it was the size of a boxcar, which would be about 50 feet long, or 15 meters, and 9 feet wide, or 2.8 meters. Another witness said it was only 20 feet long, or 6 meters. Some witnesses said it had smooth skin that looked like it was peeling all over, had a bone sticking out of its forehead, and it made sounds that one witness described as similar to both a horse’s neigh and a cow’s moo. On July 5, 1971, three-toed tracks 14 inches long, or 36 cm, were also found on an island together with crushed plants that showed a huge animal had come out of the water.

This time, at least, no one tried to dynamite or even net the monster. Instead, in 1973 Arkansas passed a law creating the White River Monster Refuge along that section of the river, to protect the monster. But no one has seen it since.

There is a photo of the monster taken in 1971, but it’s a blurry Polaroid that was reproduced in a newspaper and the original lost. The photo was taken by a man named Cloyce Warren, who was out fishing with two friends. Warren said it had “a spiny ridged backbone and [was] splashing all around.”

So what could the White River Monster be? Is it a misidentified known animal, a completely unknown animal, or just a hoax?

Obviously people are seeing something in that part of the White River. But it’s reportedly so big that if there was a population living anywhere in the river, it would be spotted all the time. So maybe it’s an animal that only sometimes strays into the White River and actually lives in the much larger Mississippi River—or even in the Gulf of Mexico, where it sometimes swims upriver.

Cryptozoologists and other interested people have made suggestions over the years. One suggestion is that it’s an elephant seal. The northern elephant seal is an enormous animal, although it’s nowhere near 50 feet long. The male is much larger than the female, up to 16 feet long, or 4.8 meters, and bulky with blubber that keeps it warm when diving deeply for food in the Pacific Ocean where it lives.

But wait, the Pacific Ocean? You mean it doesn’t live in the Gulf of Mexico?

Nope, the endangered elephant seal only lives in the Pacific. And the Pacific Ocean is separated from the Gulf of Mexico by a whole lot of the North American continent.

A man named Joe Nickell, who’s a paranormal investigator and who was interviewed on MonsterTalk episode 204, has suggested the White River Monster is a manatee—specifically the Florida manatee, which is a subspecies of West Indian manatee. In the winter it mostly lives around Florida but in summer many individuals travel widely. It’s sometimes found as far north as Massachusetts along the Atlantic coast, and as far west as Texas in the Gulf of Mexico.

The manatee is large, up to 15 feet long, or 4.6 meters, with females being somewhat larger than males. Its skin is gray but since it moves slowly, it can look mottled in color due to algae growing on its skin, and it sometimes also has barnacles stuck to it the way some whales do. It has a pair of front flippers with three or four toenails, no hind legs, and a paddle-like tail. It eats plants and only plants, and is completely harmless to humans, fish, and other animals. Also because it moves slowly and spends a lot of time at the surface, since it’s a mammal and has to breathe air, it’s vulnerable to being injured by boats.

In the 1970s there were only a few hundred manatees alive and it nearly went extinct. It was listed as an endangered species and after a lot of effort by a lot of different conservation groups, it’s now only considered threatened. So while people might recognize a manatee these days, back in the 1970s it was practically unknown everywhere except southern Florida since it was so rare. And in the decades before 1971, people didn’t travel as much and didn’t know much about increasingly rare animals that didn’t live in their particular part of the world.

In other words, it’s completely possible that people from Arkansas would see a manatee in 1915, 1937, and 1971 and not know what it was. But could a manatee really travel that far from the ocean and survive?

The Mississippi River empties into the Gulf of Mexico in Louisiana in the United States. Texas is to the west of Louisiana, then Mississippi, Alabama, and Florida to the east. In other words, it’s well within the known range of the Florida manatee. Manatees are known to sometimes travel up the Mississippi. This happened most recently in October of 2016 when a manatee traveled as far as Memphis, Tennessee before it was found dead in a small lake connected to the river. That’s a distance of 720 miles, or 1,158 km, and that was with wildlife officials trying to capture it to return it to the Gulf. That same year a manatee also traveled as far as Rhode Island along the Atlantic coast. Memphis is actually much farther up the Mississippi than the White River is, so if the manatee had branched off into the White River it might have led to new sightings of the White River Monster.

The manatee can live in fresh water perfectly well. One species, the Amazonian manatee, is a fully freshwater animal that never leaves the South American rivers where it lives. But despite its size, the manatee doesn’t have a lot of blubber or fat to keep it warm. The farther away it travels from warm water, the more likely it is to die of cold.

But while an errant manatee might explain some White River Monster sightings, it doesn’t fit with all of them. Other animals from the Gulf of Mexico sometimes find their way up the Mississippi too. It’s a huge river, and since an ocean animal doesn’t understand what a river is, it doesn’t know it’s never going to reach the ocean again unless it turns around. Most marine animals can’t survive for long in fresh water, but some animals, like the manatee, can tolerate fresh water much better. That’s also the case for the bull shark.

In 1937, the same year the White River Monster was spotted for the second time, a five-foot bull shark, or 1.5 meters, was caught in Illinois, which is even farther upstream from the Gulf of Mexico than Tennessee and Arkansas. Bull sharks live throughout much of the world’s oceans in warmer water near coasts and are often found in rivers and lakes, although they don’t live as long in fresh water as they do in salt water. The largest bull shark ever measured was 13 feet long, or 4 meters, so a large one is about the size of a manatee.

Occasionally a dolphin travels up the Mississippi River, but marine dolphins can’t survive for long in fresh water and will die soon if they can’t make their way back to the ocean. A dolphin in fresh water starts to develop skin lesions and then the skin begins to peel, leading to bacterial infection and death. Remember that some witnesses in 1971 described the White River Monster as a gray animal with peeling skin.

Nine different species of dolphin and many species of whale live in the Gulf of Mexico. Of those, only the bottlenose dolphin lives close to the coast and is usually the species that accidentally travels into fresh water and can’t find its way out. The bottlenose dolphin isn’t any larger than the manatee, up to about 13 feet long, or 4 meters.

1971 was an active hurricane year, including the category 5 Hurricane Edith that killed 37 people in mid-September. Marine animals that can travel quickly, like dolphins and sharks, will flee to calmer waters when a hurricane approaches, and while that usually means out to sea, it wouldn’t be out of the question for a frightened dolphin or other large marine animal to make its way into the Mississippi by accident ahead of a hurricane, especially a hurricane as big as Edith.

Another possible identity for the White River Monster is one that was suggested in 1937, the alligator gar. It’s a freshwater fish that lives throughout the Mississippi River and other rivers and lakes in the southern United States and parts of northern Mexico. The alligator gar gets its name because of its toothy jaws, which do resemble an alligator’s, and it can grow up to ten feet long, or 3 meters. It’s a really weird fish and eventually I’ll probably do a full episode on it and its relatives, just as I have a full episode planned about the manatee. It has gills like other fish, but it can also breathe air through its swim bladder, which is lined with lots of blood vessels that absorb oxygen. Every so often an alligator gar will come to the surface and gulp air to replenish the oxygen in its swim bladder, so it would be seen at the surface briefly but periodically as was described by many witnesses. This is also the case for the manatee and dolphin, who breathe air.

The alligator gar is an ambush predator, which means it waits in the water without moving much at all until an animal approaches. Then it shoots forward and grabs it. It mostly eats small fish, invertebrates of various kinds, and waterfowl like ducks.

The final possibility of the White River Monster’s identity is the gulf sturgeon. It’s a subspecies of the Atlantic sturgeon that lives in the Gulf of Mexico, although it’s also known from various rivers in the southeastern United States. The reason it’s found in rivers is that the gulf sturgeon is anadromous [a-NADro-mus], the term for a fish that migrates from the ocean into fresh water to spawn. The salmon is the most famous anadromous fish, which fights its way upriver to spawn and then die. In the case of the gulf sturgeon, it hatches in fresh water and lives there for the first two years or so of its life before making its way downstream to the ocean. Then it returns to freshwater to spawn every spring, usually the same river where it was hatched, and goes back to the ocean in autumn.

The gulf sturgeon fits a lot of the descriptions of the White River Monster sightings. It’s covered with five rows of scutes that project from the back and sides in a sort of low sawtooth pattern, which fits the “spiny ridged backbone” that Cloyce Warren reported seeing in 1971, and its elongated snout has sensory barbels like a catfish, which matches Bramlett Bateman’s 1937 description of the monster having the face of a catfish. It’s gray, gray-green, or brownish in color with a lighter belly, and it can grow up to 15 feet long, or 4.5 meters, although most are about half that length.

The gulf sturgeon usually migrates in groups, but occasionally one can get separated from its group and find its way into a stretch of water by itself. It also doesn’t eat much during the summer when it’s in freshwater. In the winter it lives just off the coast in shallow water, where it’s a bottom feeder. It sucks up invertebrates from the sea floor, feeling for them with their barbels. It gains lots of weight during the winter and then loses it all in the summer. Sturgeons do sometimes jump out of the water, especially in summer–as much as fix feet out of the water. No one’s sure why. Also during the summer, the sturgeon makes a sound like a creaky hinge.

I think it’s probable that the White River Monster sightings are of more than one type of animal, and while we can make an educated guess as to which animals might have been spotted and misidentified, we can’t know for sure. So while at least some of the sightings may have been of a manatee or a gulf sturgeon or another of the animals we talked about today, there’s also the possibility that something else occasionally swims up the Mississippi from the Gulf and into the White River. Hopefully, next time the White River Monster appears, someone gets a really good look at it and some good pictures so we know for sure.

This is what a sturgeon sounds like, by the way:

[sturgeon creaky sound]

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

Thanks for listening!

Episode 152: The Freshwater Seahorse and Other Mystery Water Animals

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This week let’s look at some (mostly) smaller mystery animals associated with water! Thanks to Richard J., Janice, and Simon for the suggestions!

Further reading:

What Was the Montauk Monster?

The black-striped pipefish. Also, that guy has REALLY BIG FINGERTIPS:

The Pondicherry shark, not looking very happy:

A ratfish. What BIG EYES you have!

The hoodwinker sunfish, weird and serene:

The Montauk monster, looking very sad and dead:

Show transcript:

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

Let’s finish off the year with an episode about a few mystery animals, specifically a few mystery animals associated with water. Thanks to Richard, Janice, and Simon for the suggestions!

We’ll start off with a mystery suggested by Richard J, but not the Richard J. who is my brother. A different Richard J. Apparently half the people who listen to my podcast are named Richard, and that’s just fine with me.

Richard wanted to know if there are there such things as freshwater seahorses. We’ve talked about seahorses before in episode 130, but seahorses are definitely marine animals. That means they only live in the ocean. But Richard said he’d heard about a population of seahorses native to Lake Titicaca in Bolivia, which is in South America. I put it on my suggestions list, but Richard was on the case. He sent me a link to an article looking into the mystery, which got me really intrigued, so I bumped it to the top of my list. Because I can do that. It’s my podcast.

Freshwater seahorses are supposedly known in the Mekong River and in Lake Titicaca, and sometimes you’ll see reference to the scientific name Hippocampus titicacanesis. But that’s actually not an official scientific name. There’s no type specimen and no published description. Hippocampus is the generic name for many seahorse species, but like I said, they’re all marine animals and there’s no evidence that any live in freshwater at all. Another scientific name supposedly used for the Mekong freshwater seahorse is Hippocampus aimei, but that’s a rejected name for a seahorse named Hippocampus spinosissimus, the hedgehog seahorse. It does live in parts of the Indo-Pacific Ocean, including around Australia, especially in coral reefs, and sometimes in the brackish water at the Mekong River’s mouth, but not in fresh water.

On the other hand, there’s no reason why a seahorse couldn’t adapt to freshwater living. A few of its close relatives have. There are a few species of freshwater pipefish, and in the world of aquarium enthusiasts they are actually sometimes called freshwater seahorses. The pipefish looks like a seahorse that’s been straightened out, and most of them are marine animals. But some have adapted to freshwater habitats.

This includes the black-striped pipefish, which is found off the coasts of much of Europe but which also lives in the mouths of rivers. At some point it got introduced into the Volga River and liked it so much it has started to expand into other freshwater lakes and rivers in Europe.

The pipefish is closely related to the seahorse, but while it does have bony plates like a seahorse, it’s a flexible fish. It swims more like a snake than a fish, and it can anchor itself to vegetation just like a seahorse by wrapping its tail around it. It mostly eats tiny crustaceans and newly hatched fish, since it swallows its food whole. It usually hides in vegetation until a tiny animal swims near, and then it uses its tube-shaped mouth like a straw to suck in water along with the animal. Just like the seahorse, the male pipefish has a brooding pouch and takes care of the eggs after the female deposits them in his pouch.

So where did the rumor that seahorses live in the Mekong come from? The Mekong is a river in southeast Asia that runs through at least six countries, including China, Thailand, Cambodia, and Vietnam. Parts of it are hard to navigate due to waterfalls and rapids, but it’s used as a shipping route and there are lots of people who live along the river. Like all rivers, it’s home to many interesting animals, including a type of giant softshell turtle that can grow up to six feet long, or 1.8 meters, a type of otter, a bunch of enormous fish, including three species of catfish that can grow up to almost ten feet long, or 3 meters, and a giant freshwater stingray that can grow up to 16 feet long, or 5 meters, and of course lots more animals that aren’t as big or as impressive, but which are still important to the river’s biodiversity. But there’s no evidence of seahorses anywhere throughout the Mekong’s 2700 mile length, or 4,350 km.

But there is a hint about where the rumor of a Mekong seahorse could have come from. One researcher named Heiko Bleher chased down the type specimens of the supposed Mekong seahorse in a Paris museum, which were collected in the early 20th century by a man named Roule. Roule got them in Laos from a fisherman who had nailed the dried seahorses to his fishing hut. The fisherman told Roule the seahorses were from the Mekong, but when they were further studied in 1999 Roule’s specimens were discovered to actually be specimens of Hippocampus spinosissimus and Hippocampus barbouri. Both are marine fish but do sometimes live in brackish water at the mouth of the Mekong. So the fisherman wasn’t lying, but Roule misunderstood what he meant.

As for the freshwater seahorse supposedly found in Lake Titicaca, that one’s less easy to explain. Titicaca is a freshwater lake in South America, specifically in the Andes Mountains on the border of Bolivia and Peru. It’s the largest lake in South America and is far, far above the ocean’s surface—12,507 feet above sea level, in fact, or 3,812 meters. It’s also extremely deep, 932 feet deep in some areas, or 284 meters. It’s home to many species of animal that live nowhere else in the world. Why couldn’t it be home to a freshwater seahorse too?

Titicaca was formed when a massive earthquake some 25 million years ago essentially shoved two mountains apart, leaving a gap—although technically it’s two gaps connected with a narrow strait. Over the centuries rainwater, snowmelt, and streams gradually filled the gaps, and these days five rivers and many streams from higher in the mountains feed water into the lake. Water leaves the lake by the River Desaguadero and flows into two other lakes, but those lakes aren’t connected to the sea. Sometimes they dry up completely. So Titicaca isn’t connected to the ocean and never was, and even if it was, seahorses are weak swimmers and would never be able to venture up a river 12,000 feet above sea level. Some 90% of all fish in the lake are found nowhere else in the world. There’s just simply no way a population of seahorses could have gotten into the lake in the first place, even if they could survive there.

That doesn’t mean there aren’t any freshwater seahorses out there ready to be discovered, of course. But I don’t think you’re going to find any in Lake Titicaca. And I have no idea how the rumor got started that any live there.

From a tiny seahorse let’s move on to a small shark, another topic suggested by Richard J. The Pondicherry shark grows to about 3.3 feet, or 1 meter, and once lived throughout the Indo-Pacific, especially in coastal waters. It’s considered critically endangered, but it’s so rare these days that we hardly know anything about it except that it’s harmless to humans, eats small fish and other small animals, and was once common. But until the mid-2010s, scientists were starting to worry it was already extinct. Then in 2016 two different Pondicherry sharks were photographed in two different places—and not where anyone had expected to find it. Some tourists took a photo of one in a river called the Menik and a freshwater fish survey camera caught a photo of one in the Kumbuk River. Both rivers are in Sri Lanka. Since then researchers have spotted a few more. The shark is protected, and hopefully the excitement around the shark’s rediscovery has helped people in the area learn about it so they know not to bother it. Some sharks tolerate fresh water and brackish water quite well, so it’s not surprising that the Pondicherry shark has moved into the rivers where it has less competition from commercial fishing boats.

Our next water mystery is actually not really a mystery, just a really strange-looking fish related to sharks. This one was suggested by my aunt Janice who doesn’t actually listen to the podcast but who likes to send me links to strange animal articles that she comes across on the internet. This one is called Chimaera Monstrosa, sometimes called the rat fish.

The rat fish mostly lives in the deep sea, although it’s sometimes seen in shallower water, and can grow up to 5 feet long, or 1.5 meters. It’s mostly brown but has white markings. Its body looks more or less like a regular plump shark-like fish, but it has great big round green eyes, relatively long pectoral fins, and a very long tail that tapers to a point. The tail gives it its common name, since it kind of resembles a rat’s tail. It eats whatever it can catch on the ocean floor, including crustaceans and echinoderms.

Ratfish, and other chimaeriformes, are most closely related to sharks, and like sharks they have skeletons that are made of cartilage instead of bone. Since they’re rarely seen and look really weird, every so often someone catches one and posts about it online, and then my aunt sends me a link. They are really interesting fish, though.

Simon also sent me an article about an interesting fish a while back, the hoodwinker sunfish. We talked about the sunfish, or mola mola, in episode 96. The hoodwinker sunfish, or mola tecta, was only discovered in 2017 despite its large size. So far it’s known to live in the South Pacific around New Zealand, Australia, South Africa, and Chile, but only off the southernmost parts of those countries. But in early 2019 one washed up in Southern California.

The mystery sunfish was measured at almost 7 feet long, or 2.1 meters. An intern at the University of California at Santa Barbara found it, but didn’t know what it was. But once photos of the fish were posted online, two experts from Australia recognized it immediately—but because it showed up so far out of its known range, they were cautious about IDing it from just a photo. That’s despite the fact that one of the experts, Marianne Nyegaard, was actually the person who named the species. She asked for samples and more photos, and when she got the results, it really was a hoodwinker sunfish. But what was it doing in the warm waters of the northern Pacific instead of the cold southern waters? No one knows except the sunfish.

Let’s finish with another mystery animal you may have heard of. On July 12 or 13, 2008, depending on which source you consult, three friends visited Ditch Plains Beach, two miles away from the little town of Montauk in New York state in eastern North America. It was a hot day and the beach was crowded, and when the three noticed people gathered around something, they went to look too. There they saw a weird dead animal that had obviously washed ashore. One of the three took a picture of it, which appeared in the local papers and then the local TV news along with an interview with the three. From there it went viral and was dubbed the Montauk monster.

The monster was about the size of a cat, but with shorter legs and a chunkier body, and a relatively short tail. It didn’t have much hair but it did have sharp teeth, and the front part of its skull was exposed so that it almost looked like it had a beak. Its front paws were elongated with long fingers, almost like little hands.

So what was the monster? People all over the world made guesses, everything from a sea turtle without a shell to a diseased dog or just a hoax. Some people thought it was a mutant animal that had been created in a lab on one of the nearby islands, escaped, and died trying to swim to the mainland.

But while no one knows what happened to the animal’s body, scientists have studied the photo and determined that it was probably a dead raccoon that had been washed into the ocean. The waves had tumbled the animal’s body around through the sand long enough to rub off most of its remaining fur and some of its facial features, and then it washed ashore during the next high tide. It was also somewhat bloated due to gases building up inside during decomposition. It’s the animal’s teeth and paws that made the identification possible, since both match a raccoon’s exactly. Remember that raccoons have clever front paws that help them open locking trash bins, as we learned in episode 138.

So the Montauk monster isn’t actually a mystery, except what happened to it, but don’t be discouraged. There are still lots of genuinely mysterious animals in the ocean, from misplaced sunfish to creatures no one has ever seen yet. Maybe you’ll be the one to discover them.

You can find Strange Animals Podcast online at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon at Patreon.com/strangeanimalspodcast if you’d like to support us and get twice-monthly bonus episodes.

Thanks for listening!

Episode 151: Fossils with other fossils inside

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Thanks to Pranav who suggested this week’s amazing topic, animals that fossilized with the remains of their last meal inside!

Indrasaurus with a lizard inside. Yum!

Baryonyx:

Rhamphorhynchus (left, with long wing bones) and its Fish of Doom (right):

The fish within a fish fossil is a reminder to chew your food instead of swallowing it alive where it can kill you:

The turducken of fossils! A snake with a lizard inside with a bug inside!

Show transcript:

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

This week we have a listener suggestion from Pranav, who has sent me so many amazing suggestions that he has his own page on the ideas spreadsheet. When he emailed me about this one, he just suggested cool fossils, but the links he provided had a really interesting theme that I never would have thought about on my own. This week we’re going to learn about some fossil animals that have fossils of their last meal inside them!

We’ll start with a recent discovery of a new microraptor species, Indrasaurus wangi, which lived about 120 million years ago. It was an interesting animal to start with, because it had arms that were very similar to bird wings, although with claws, but its hind legs also had long feathers that made it almost like a four-winged animal. It was found in 2003 in northeastern China, but when researchers were studying it in 2019 they found something amazing. Not only did it have an entire lizard skeleton where its stomach once was, showing us that it swallowed its prey whole, the lizard itself was a species new to science.

We know what else Indrasaurus ate because more Indrasaurus fossils have been found in the area, many of them so well preserved that its fossilized stomach contents have been preserved too. It ate mammals, birds, lizards, and fish—basically anything it could catch.

Another species that was similar to Indrasaurus, called Anchiornis, also called a four-winged bird-like dinosaur, was found with what appears to be a gastric pellet in its throat. The pellet contains the bones of more than one lizard and was probably ready to be horked up the way many carnivorous birds still regurgitate pellets made up of the indigestible parts of their prey, like bones, scales, and fur.

The fossilized remains of food inside a fossilized organism has a term, of course. It’s called a consumulite. It’s a type of bromalite, which is a broader term for any food or former food found in a fossilized organism’s digestive tract. The term bromalite also includes coprolites, which are fossilized poops.

Naturally, it requires a high degree of preservation for consumulites to form, and a high degree of skill to reveal the often tiny and delicate preserved details. And consumulites are important because they let us know exactly what the animal was eating.

Consumulites aren’t limited to prey animals, either. A small armored dinosaur, a type of ankylosaur, called Kunbarrasaurus, which lived around 115 million years ago in what is now Australia, was a herbivore. The type specimen of the species, which was described in 2015, was incredibly well preserved—almost the entire skeleton, most of its body armor, and the contents of its stomach. Paleontologists can determine not just what kinds of plants it had eaten—which include ferns and seeds—but how it was processing its food. Most herbivorous dinosaurs swallowed leaves and other plant parts whole, then crushed the food in a powerful gizzard or gizzard-like organ along with rocks or grit. The rocks helped break up the plant material, and we have lots of these rocks associated with fossilized dinosaurs. The rocks are called gastroliths and are usually worn smooth. But Kunbarrasaurus didn’t have any gastroliths, and the plant material was so well preserved that researchers could see the cut ends of the plants where Kunbarrasaurus had bitten them. And all the pieces were small. Kunbarrasaurus therefore probably chewed its food, which meant it also probably had lips and cheeks of some kind to help keep the food in its mouth while it was chewing.

Another example of an animal with a consumulite that helped solve a mystery about its diet is Baryonyx. Baryonyx is a type of spinosaurid, a theropod dinosaur that grew at least 33 feet long, or 10 meters. It was discovered in 1983 in Surrey, England, and was described in 1986. It lived around 125 million years ago. It walked on its hind legs and probably used its arms to tear its prey into bite-sized pieces, because its first finger had a huge claw 12 inches long, or 31 cm.

But its skull was the real puzzle. Most theropods are meat-eaters, although a few evolved to eat plants. But Baryonyx had a long, relatively slender snout with a lot of close-growing teeth, and a sort of bulb at the end of its snout called a rosette. It looks more like the skull of a crocodilian called a gharial than a theropod. But as far as anyone knew when Baryonyx was discovered, there were no fish-eating theropods.

Until 1997, that is, when paleontologists studying Baryonyx spotted some overlooked details. In addition to a gastrolith in its belly area, they found some fish scales and teeth that showed evidence of being damaged by digestive acids. It probably hunted by wading through shallow water like a heron, catching fish and other animals with its long toothy snout.

It’s not just dinosaurs that are found with consumulites. Animals of all kinds eat all the time, so as long as the conditions are right to fossilize the remains of an animal, there’s a chance that whatever food was in the digestive tract might fossilize too. For instance, the same part of China that has yielded amazingly well preserved feathered dinosaurs has also produced other animals—including a carnivorous mammal called Repenomamus that grew more than three feet long, or one meter. I think we’ve talked about Repenomamus before, because we have evidence that it actually ate dinosaurs—at least baby ones, or it might have scavenged already dead dinosaurs. Either way, it lived around 125 million years ago and was shaped sort of like a badger with a long tail, although it wasn’t related at all to badgers or any other modern mammal. It probably laid eggs like monotremes still do. The reason we know what Repenomamus ate is because one specimen was found with pieces of a young Psittacosaurus in its stomach.

In at least one case it’s hard to tell which animal should be considered the eater and which should be considered the eaten. A fossil slab found in Southern Germany and described in 2012 contains a Rhamphorhynchus associated with two different fish.

Rhamphorhynchus lived around 150 million years ago and was a type of pterosaur with a long tail. Its wingspan was about six feet across, or 1.8 meters. It mostly ate fish, which it probably caught not by flying down to grab fish out of the water, like eagles do, but by floating like a goose and diving for fish. It had large feet and short legs, which would have helped it take off from the water just like a goose.

A fish that lived at the same time as Rhamphorhynchus was called Aspidorhynchus, and it grew up to two feet long, or 60 cm. It had long jaws filled with teeth, with the upper jaw, or rostrum, extending into a pointy spike.

In the fossil found in Germany, a Rhamphorhynchus has a small fish in its throat that it had probably just caught. While it was still swallowing it, an Aspidorhynchus fish attacked! But things obviously went wrong for everyone involved. Researchers suggest that the fish’s rostrum cut right through the flying membrane of Rhamphorhynchus’s left wing. The fish bit down but its teeth became tangled in the tissue. It started thrashing to free itself and Rhamphorhynchus was thrashing around too trying to get away, which only got them more tangled up together. The fish dived, drowning Rhamphorhynchus, and the weight of its body dragged Aspidorhynchus into deep water where there wasn’t enough oxygen for it to survive. It died too, and its heavier body lay partially across Rhamphorhynchus, holding it down so it wouldn’t drift away. The fossil shows Rhamphorynchus, Aspidorhynchus, and the tiny fish that Rhamphorhynchus never did get to finish swallowing.

Another fish, Cimolichthys, lived around 75 or 80 million years ago and grew a little over six feet long, or two meters. Its body was heavily armored by large scutes and it had several rows of teeth. It may have been related to modern salmon. It lived in what is now North America and Europe, and ate fish and squid. We know it ate fish and squid because, of course, we have the remains of various last meals found with preserved fossil Cimolichthys. For instance, one specimen was found with the internal shell of a cephalopod lodged in its throat. Researchers suspect the fish had tried to swallow a Tusoteuthis that was too big to fit down its throat. The Tusoteuthis got stuck and blocked the flow of water over the fish’s gills, basically drowning it. Tusoteuthis, by the way, could possibly grow up to 36 feet long, or 11 meters, although that depends on whether it had long feeding tentacles like modern squid or not. If it didn’t have long feeding tentacles, it was probably only about 19 feet long, or 6 meters, which is pretty darn big anyway. I wouldn’t want to have to swallow that thing whole. Not even if it was deep-fried first.

Another fish called Xiphactinus, which grew up to 20 feet long, or 6 meters, lived in the late Cretaceous period. It died out at the same time as the non-avian dinosaurs. It had massive fangs and was a terrifying predator, but sometimes that backfires. The fossil of a 13 foot, or 4 meter, Xiphactinus was found with a 6 foot long, or 1.8 meter, fish called Gillicus inside it. Paleontologists think Xiphactinus swallowed its prey whole, which thrashed around so much inside it that it ruptured an organ and killed the predator fish. Both fish sank to the bottom of the shallow Western Interior Seaway in North America until it was discovered in 1952.

Let’s finish with two even more incredible fossils. In 2008 paleontologists found a fossilized freshwater shark they dated to 250 million years ago. Right before it died, it had eaten two animals called temnospondyls. Temnospondyls were common animals, with many species found throughout the world, and researchers still aren’t sure if they were the ancestors of modern amphibians or a similar type of animal that died out without any descendants. One of the temnospondyls that the shark ate had the well digested remains of a spiny fish in its stomach.

But a few years later researchers in Germany found something even better. It’s a fossilized snake called a Palaeopython, related to boas. It was about three feet long, or one meter, and was still young. If it had lived to grow up, it would have doubled in size. It lived in trees but also hunted along the edges of rivers and lakes. About 48 million years ago, this particular snake caught a lizard that’s related to modern basilisk lizards. It swallowed the lizard headfirst. But then the snake died, possibly asphyxiated by a cloud of carbon dioxide from the volcanic lake nearby. We have a lot of incredibly detailed fossils from that lake, known as the Messel Pit.

Researchers aren’t sure how the snake made it into the lake. Maybe it was already in the shallow water when it died, or on the bank, and a wave washed it into the water. Maybe the wave was actually what killed the snake, washing it into the lake where it drowned. However it died, it sank into deep water and was covered in sediment that preserved it. Then, 48 million years later, paleontologists found it.

When the fossil was cleaned and prepared for study, researchers found that the lizard was preserved inside it. But there was another surprise inside the lizard! Right before it had been eaten by the snake, the lizard had eaten an insect. And the insect was so well preserved that researchers could tell it had an iridescent exoskeleton.

If I was fossilized right now, paleontologists from the far future would find a lot of chocolate in my stomach. Happy holidays to everyone, whatever your reason for celebrating at this time of year!

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

Thanks for listening!

Episode 137: The Orca, Jolly Terror of the Seas

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Thanks to Pranav for this week’s topic, the orca or killer whale!

Further reading:

https://www.nationalgeographic.com/animals/2019/07/killer-whales-orcas-eat-great-white-sharks/

Save Our Seas Magazine (I took the Jaws art below from here too)

An orca:

Orcas got teeth:

Starboard and Port amiright:

Show transcript:

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

This week let’s return to the sea for a topic suggested by Pranav, the orca. That’s the same animal that’s sometimes called the killer whale. While it is a cetacean, it’s more closely related to dolphins than whales and is actually considered a dolphin although it’s much bigger than other dolphin species.

The orca grows up to 26 feet long, or 8 meters, and is mostly black with bright white patches. The male has a large dorsal fin that can be 6 feet tall, or 1.8 meters, while females have much shorter dorsal fins that tend to curve backwards more than males’ do. Some orcas have lighter coloring, gray instead of black or with gray patches within the black.

The orca lives throughout the world’s oceans although it especially likes cold water. It eats fish, penguins and other birds, sea turtles, seals and sea lions, and pretty much anything else it can catch.

Everything about the orca is designed for strength and predatory skill. It has good vision, hearing, sense of touch, and echolocation abilities. It’s also extremely social, living in pairs or groups and frequently hunting cooperatively.

Some populations of orca live in the same area their whole lives, traveling along the same coastline as they hunt fish. These are called resident orcas and they’re closely studied since researchers can tell individuals apart by their unique markings, so can keep track of what individuals are doing.

Other populations are called transient because they travel much more widely. Transient and resident orcas avoid each other, so they may be separate species or subspecies, although researchers haven’t determined whether this is the case yet. There’s even a newly discovered population of orcas found off the tip of South America that may be a new species. Researchers are analyzing DNA samples taken from the South American orcas with little darts. Fishers had reported seeing odd-looking small orcas in the area for over a decade, but recent photos taken by tourists gave researchers a better idea of what they were looking for. The new orcas have rounder heads and different spotting patterns than other orca populations.

Transient orcas eat more mammals than resident orcas do. Resident orcas mostly eat fish. They have clever ways of catching certain fish, too. A pod of orcas can herd herring and some other fish species by releasing bubbles from their blowholes, which frighten the fish away. A group of orcas releasing bubbles in tandem can make the school of fish form a big ball for protection. Then each orca slaps the ball with its tail. This stuns or even kills some of the fish, which the orca then eats easily. Pretty clever. An orca may also stun larger fish by smacking it with its powerful tail flukes.

But the orca is also good at catching seals and sea lions. Some orcas learn to beach themselves safely when chasing seals, since the seal will often try to escape onto land. Another hunting technique is called wave-hunting, where a group of orcas swim in a way that causes waves to slop over an ice floe. Any animal or bird resting on the ice floe is washed into the water.

Because transient orcas mostly hunt mammals that can hear the orcas’ echolocation clicks and other vocalizations, they tend to stay silent while hunting so they don’t alert their prey. Resident orcas don’t have to worry about noise as much, since most of the fish they eat either can’t hear or their calls or don’t react to them. Resident orcas are much more vocal than transient orcas as a result.

But all orcas have calls they use socially. These are calls that help members of the pod stay in contact, help them coordinate hunting activities, and identify themselves to members of other pods. A pod is usually made up of several family groups, usually ones that are related in some way. You know, like the orca equivalent of an extended family—you and your mom and siblings, maybe your dad, and your mom’s sister and her babies, and so on. Each pod has its own dialect, with their own calls not heard in other pods.

Orcas are also incredibly intelligent and show social traits that match those of humans and chimpanzees, like playfulness, cooperation, and protectiveness. Their social structure is also complex and similar in many ways to those of humans and other great apes. As you may remember from episode 134 about the magpie, complex social structures lead to intelligence in individuals. Individual orcas have what’s known as signature whistles, a unique vocalization that only applies to that one orca. In other words, orcas have names. Researchers have also identified signature whistles in other dolphin species.

Because orcas are so large, so social, so intelligent, and travel such enormous distances every day—up to 50 miles, or 80 km—it doesn’t make any sense to keep them in captivity. But there are a lot of orcas in captivity. In the last decade or so people have started to realize that maybe this is not good for the orcas. Captive orcas develop mental and physical problems that they don’t have in the wild, including bad teeth. A 2017 study of captive orcas found that all of them had tooth problems and more than 65% of them had teeth so worn that the tooth pulp was exposed. That’s the sensitive part of your tooth, so you can imagine the agony this must cause the orca. It’s so bad that over 61% of the orcas studied had had the pulp removed from some of their teeth, which at least stops the pain but which leaves the orca more prone to infection and disease, plus weakens the tooth and can lead to it cracking. Such awful tooth problems mostly result from the orca chewing on concrete and steel in its tank, and this kind of chewing is due to extreme anxiety and other mental problems due to captivity. It’s not seen in orcas in the wild at all. So no, there shouldn’t be any orcas in captivity, or any other cetaceans, unless it’s for rehabilitation purposes with the goal of releasing the orca back into the wild after it’s healthy again.

The orca can live to be at least 90 years old, possibly older. Females especially live much longer than males overall. Female orcas lose the ability to have babies after about age 40 and enter a stage of life called menopause. Humans do this too, and studies show that it’s for the same reasons. Older females help younger females care for their children, and they’re also group leaders who teach younger orcas where to find food and how to catch it.

The orca is an apex predator, meaning there is nothing in the wild that hunts and eats it. Even the great white shark. On average the orca is larger than the great white, and it has an advantage because it hunts cooperatively. Where there are orcas around, there are usually not any great white sharks. This is partly because the two species eat the same thing and the orca out-competes the shark, but it’s also because the orca can and will eat great white sharks.

Some orcas have figured out that they can turn a shark upside down and keep it there in order to hypnotize it. This is called tonic immobility and researchers aren’t entirely sure why it happens, but the shark remains immobile until it wears off after a few minutes. It doesn’t work in all shark species or for every shark, but it makes the shark a lot easier for the orca to kill since it can’t fight back. In 1997 witnesses saw an orca hold a great white upside down for 15 minutes, trying to hypnotize it. It didn’t work, but since sharks have to keep moving to breathe, since they can’t pump water through their gills otherwise, the shark in question actually suffocated and the orca ate it.

But a pair of orcas have taken predation of great white sharks to a whole new level.

The phenomenon was first spotted in 1997 off the coast of San Francisco in western North America. People in a whale-watching tour saw two orcas attack a great white shark and eat its liver. Just its liver. They knew exactly where the liver was and aimed for it during the attack. A great white’s liver is huge and full of yummy fat.

Later that year, researchers studying elephant seals in the area noticed that all the great white sharks that usually preyed on seal colonies had vanished. They’d actually moved out of the area instead of staying to eat the seals. Studies of tagged great whites determined that they avoided orcas to the point of migrating away from feeding sites entirely if orcas were around.

Twenty years later, a marine biologist in South Africa named Alison Kock studied a pair of orcas named Starboard and Port who were attacking sharks the same way and eating their livers. Initially they targeted sevengill sharks, which can grow up to ten feet long, or 3 meters. But all the sevengill sharks fled and in 2017 the carcasses of great white sharks started to wash ashore with their livers eaten. Dr. Kock was pretty sure Starboard and Port were the culprits. When she studied the dead sharks, she recognized tooth marks from orcas.

Remember how earlier I said there were two types of orcas known, the residential and the transient groups? Plus the newly discovered group? Well, there’s actually a fourth group called the offshore orca. These are populations of orcas that live farther away from shore than most other groups. They travel widely and are the only orcas known in the wild to have teeth that are worn down flat almost like the captive orcas. Researchers think the offshore orcas specialize in hunting sharks and their relatives, and that the tooth wear comes from the sharks’ rough skin. Unlike the captive sharks, the tooth wear doesn’t affect the orcas’ overall health. Studies of offshore orcas have determined that more than 93% of their diet is made up of sharks.

Starboard and Port are now mostly after the bronze whaler shark, which grows up to 11 feet long, or 3.3 meters. No shark is safe.

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

Thanks for listening!

Episode 130: Strangest Small Fish

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This week we’re going to revisit a suggestion from Damian and follow up on episode 96, our strangest big fish episode. This time let’s find out about some weird small fish!

The teeny, newly-discovered American pocket shark:

The brownsnout spookfish wears its mirror sunglasses on the INSIDE:

The goblinfish with a dangerous head and basically a dangerous everything else too:

Two teeny pygmy seahorses. Can you spot them? Hint: they’re the ones with eyes.

The razorfish. Just another sea urchin spine, no fish to see here:

The much-maligned candiru:

The red-lipped batfish:

Gimme kiss:

Show transcript:

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

Ages ago, Damian suggested an episode about weird fish. We covered some weird big fish in episode 96, but now it’s time for some weird little fish.

So, think about sharks for a second. Big, scary, sharp teeth, fast swimmers, black eyes of a pitiless killer of the deep.

But have you perhaps considered that maybe the world needs a very small shark? One that actually kind of looks like a tiny whale? Like, a tiny shark, only about 5 ½ inches long, or 14 cm. Almost, you know, pocket sized. Oh, and it should glow in the dark.

That’s the American pocket shark, a real animal that was only discovered in 2010! It’s called a pocket shark not because it’s pocket sized, although it is, but because it has a sort of pocket on each side near its gills that produces luminous fluid. Researchers aren’t sure whether the shark uses the fluid for attracting prey or avoiding predators. Maybe both. Its head is bulbous and rounded, which kind of makes it look like a tiny whale.

The American pocket shark was discovered in the Gulf of Mexico while scientists were observing sperm whales and tracking them with sonar. When a whale surfaced from a dive, the research team dropped nets to the depth the whale had dived to, hoping to catch the same kind of prey the whales were eating. And one of the things they found in the net was a tiny shark new to science, found at a depth of 3,000 feet, or 914 meters.

In 2013 the tiny shark, which had been frozen for later study, was finally examined. The expert who looked at it had only seen one other shark like it before, a shark discovered in the eastern Pacific in 1979. But this tiny shark had some differences from that tiny shark, and after examining both specimens carefully, they’ve been classified as different species.

So that’s a cute start, but it’s still just a rare little shark that glows. Not really that unusual, right? Let’s look at a really weird fish next. Like, seriously weird.

It’s called the brownsnout spookfish, which is a really terrible name, but it’s not a terrible fish. I mean, it couldn’t hurt you. It grows about 7 inches long, or 18 cm, and eats copepods and other tiny crustaceans. Its snout is long and kind of pointy, its body is slender, and it has elongated pelvic fins. Because it lives in the deep sea, it has eyes that point upward, which help it see predators and prey that might be silhouetted against the far-distant surface of the ocean. But it also has something only one other fish is known to have, an extra structure to the side of the eyeball. It’s called a diverticulum and it does two things. First, it allows the fish to see downward in addition to upward, and second, it allows it to see across a really wide angle. The diverticulum does this because it contains a mirror that reflects light from the main eyeball onto the retina of the diverticulum. A MIRROR IN ITS EYEBALLS. The mirror is made up of tiny crystalline plates.

Some invertebrates like clams and crustaceans contain reflectors in their eyes, but except for the brownsnout spookfish, the only other vertebrate known to have mirrored eyeballs is the glasshead barreleye. Also a terrible name. The glasshead barreleye is a little smaller than the brownsnout spookfish, and not surprisingly, they’re related. But surprisingly, they’re not that closely related and the mirrored diverticulum appears to have evolved independently in each species.

Although the fish has been known to science for over a century, no one realized it had mirrors in its eyes until 2008 when a live one was caught by a deep-sea scientific expedition off the island of Tonga in the Pacific Ocean. Researchers took pictures of the brownsnout spookfish and got a shock when they looked at the photos. The upward-pointing parts of the eye reflected light normally, the typical eyeshine you get when you use a flash to photograph most animals. But the lower parts of the eyes reflected bright light. Researchers think the fish uses its downward-pointing eyes to see the faint bioluminescent flashes of its prey, while the upward-pointing eyes watch for predators approaching from above.

Oh, and I forgot to mention. The brownsnout spookfish is mostly transparent. You can see right through it. Yeah.

After that, the goblinfish that lives around reefs off the southern coast of Australia seems practically normal. It grows up to 8 inches long, or 20 cm, and spends most of its time resting among rocks on the seabed. It hunts at night, eating small crustaceans, and instead of swimming it usually walks along the sea floor with its large pectoral fins.

The goblinfish gets its name from its appearance, which is frankly ugly unless you are another goblinfish. Its head looks sort of turtle-like, including a dip in its body behind its eyes and in front of its dorsal fin that looks like a turtle’s neck. Its eyes are large and orange in color. Its dorsal fin is spiny and runs most of the length of its back. It also has broad pectoral fins that it sometimes spreads like fans. It can change color to blend in with the rocks around it, which makes it hard for divers to see, which is too bad because it’s also venomous.

It’s a type of waspfish, related to scorpionfish and stonefish, all of which are venomous. Like many of those other fish, the goblinfish has venomous spines on its fins, but it also has a spine on each side of its head, underneath its eyes. Only these spines are hidden inside the fish’s head. The spine is called a lachrymal saber, and it acts like a switchblade that the fish can extend with its cheek muscles. The lachrymal saber isn’t venomous, but if you’ve just picked one up by the head and those switchblades come out, you probably aren’t going to be happy anyway. Also, why did you just pick that fish up by its head? What is wrong with you?

Next, let’s talk about the seahorse. It’s a fish although it doesn’t look like an ordinary fish. And in fact nothing about the seahorse is ordinary.

Unlike most fish, the seahorse has a flexible neck. Also unlike almost all other fish it swims vertically, with its head up and its tail down. It has a prehensile tail made up of 36 bony segments, and each segments is made of four pieces connected by tiny joints. The joints make the segments incredibly strong and able to withstand considerable pressure without breaking. The seahorse uses its tail to hold onto seaweed or other items to keep from being swept away in currents, since it isn’t a strong swimmer. It propels itself through the water by fluttering its dorsal fin, using its pectoral fins to steer. Males also fight each other by tail-wrestling and bopping their heads together. The seahorse’s body is protected with an external skeleton of bony plates, which take the place of ribs. The seahorse doesn’t have ribs. It also doesn’t have scales, just the bony plates with thin skin over them.

The seahorse lives in warm, shallow oceans throughout the world, especially in coral reefs and seagrass beds where there’s plenty of cover. The largest seahorse species grow to about 14 inches long, or 35 cm. The smallest species are barely more than half an inch long, or 15 mm. The smallest species are mostly new to science since they’re so hard to find and identify. Seahorses are well camouflaged to blend in with the plants and coral they live in.

The seahorse’s mouth is at the end of a long, tubelike snout, and it actually sucks its prey into its snout like a straw. It eats small crustaceans, larval fish, and other small animals. Oh, and its eyes can move independently of each other.

Seahorses don’t mate for life, but they do form bonds that last throughout the breeding season, and it has a long courtship period while the female develops her eggs. The pair participate in courtship dances and spend most of their time together. When the eggs are ready, the female deposits them in a special brood pouch in the male’s belly, where he fertilizes them. They then embed themselves in the spongy wall of the brood pouch and are nourished not only by the yolk sacs in the eggs, but by the male, who secretes nutrients in the brood pouch. So basically the male is pregnant. The female visits him every day to check on him, usually in the mornings. When the eggs hatch after a few weeks, the male expels the babies from his pouch and they swim away, because when they hatch they are perfectly formed teeny-tiny miniature seahorses.

If you’re wondering why I said the seahorse is almost the only fish that swims vertically, there’s some evidence that the oarfish does this too. We talked about the oarfish way back in episode 6, about sea monsters. But there’s another fish that swims vertically, the razorfish—but it swims with its head pointed down and its tail pointed up. It’s a slender fish that grows about six inches long, or 15 cm, with a pointy nose and tiny fins. Its back is protected by bony plates that extend past the tail fin in a spine. It eats tiny animals, including brine shrimp, AKA sea monkeys. When it feels threatened, the razorfish swims to the nearest sea urchin and hides among its spines, blending in with them. Schools of razorfish will swim around together, all of them head-down, because that’s just what they do.

Not all weird fish live in the ocean. A lot of freshwater fish are weird too. For instance, the candiru [kan-DEE-roo]. You’ve probably heard of this one although you may not know what it’s called. It’s native to the Amazon and Orinoco Rivers in South America and it’s actually a type of catfish. Some species grow over a foot long, or around 40 cm, but the species we’re talking about today, Vandellia cirrhosa, grows less than two inches long, or 5 cm. Like the brownsnout spookfish, it’s mostly translucent so it’s hard to see in the water. It has short spines on its gill covers that point backwards.

Unlike other catfish, the candiru eats blood, which gives it its other name of the vampire fish. It parasitizes other fish by lodging itself in their gills and sucking their blood. But the candiru is supposed to do something else, something that happens by accident. The story goes that if someone pees while in the water and a candiru is around, it’ll swim up the stream of urine, attracted by the smell, and lodge itself in the urethra of the person peeing. It’s supposed to do this thinking it’s entering the gills of a fish. Its spines keep it locked in place, causing intense pain to the person, followed by infection and, if the fish isn’t surgically removed, death.

At least, that’s the story. There’s even a 1997 video of a man who had to have a candiru removed from his penis after he peed while wading in a river in Brazil. The doctor filmed the surgery and even kept the fish he removed, preserved in formaldehyde. So it must be true, right?

Maybe not. One study determined that the candiru isn’t interested in the chemicals present in urine and in fact it hunts by sight, not smell. And a study of medical reports throughout South America only found a single instance of anyone reporting a candiru attack. That instance is the same one from 1997 where the surgery to remove the fish was filmed.

But a further study of the surgery, photos, and preserved candiru specimen tell a different story. The human urethra is extremely narrow and the preserved fish was much too large to enter without squishing itself to death, not to mention that the candiru is just not strong enough to muscle its way into anything but a larger fish’s gills. The doctor also said he’d had to cut off the candiru’s spines before removing it, but the specimen is fully intact, spines and all. It sounds like the video may be a hoax of some kind.

Reports of candiru attacks are common in parts of South America today and have been common as far back as recorded history, but they seem to be more of a legend than something that happens a lot or maybe even at all. Still, probably better not to pee into the Amazon River, just in case.

Let’s finish with the red-lipped batfish, a type of anglerfish only found around the Galapagos Islands in the Pacific Ocean. It lives on the ocean floor where the water is fairly shallow, and it grows about 8 inches long, or 20 cm. It’s usually a mottled brown, green, or grey with a white stomach, but its mouth is bright red. It looks like it’s wearing lipstick. It eats fish and other small animals, which it attracts using a lure on its head, a highly modified dorsal fin called an illicium.

The weirdest thing about the red-lipped batfish is actually its fins. It prefers to walk on the bottom of the ocean instead of swim, and it has modified pectoral fins called pseudolegs. The pseudolegs make it look a little bit like a weird frog with a tail, a unicorn horn, and lipstick. It’s like something out of a fever dream, honestly.

Researchers think the red lips may be a way to attract potential mates, presumably ones who are hoping for a big smooch.

You can find Strange Animals Podcast online at strangeanimalspodcast.blubrry.net. That’s blueberry without any E’s. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 122: Strange Shark Ancestors

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This week let’s learn about some ancestors of sharks and shark relatives that looked very strange compared to most sharks today!

Stethacanthus fossil and what the living fish might have looked like:

Two Falcatus fossils, female above, male below with his dorsal spine visible:

Xenacanthus looked more like an eel than a shark:

Ptychodus was really big, but not as big as the things that ate it:

A Helicoprion tooth whorl and what a living Helicoprion might have looked like:

Show transcript:

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

This week we’re going back in time again to learn about some animals that are long-extinct…but they’re not land animals. Yes, it’s a weird fish episode, but this one is about shark relatives!

The first shark ancestor is found in the fossil record around 420 million years ago, although since all we have are scales, we don’t know exactly what those fish looked like. The first true shark was called Cladoselache [clay-dough-sell-a-kee] and lived around 370 million years ago, at the same time as dunkleosteus and other massive armored fish. We covered dunkleosteus and other placoderms back in episode 33. Cladoselache grew up to four feet long, or 1.2 meters, and was a fast swimmer. We know Cladoselache ate fish because we have some fossils of Cladoselache with fish fossils in the digestive system—whole fish fossils, which suggests that cladoselache swallowed its prey whole. Cladoselache also had fin spines in front of its dorsal fins that made the fins stronger, but unlike its descendants, it didn’t have denticles in its skin. It didn’t have scales at all.

The denticles in shark skin aren’t just protection for the shark, they also strengthen the skin to allow for the attachment of stronger muscles. That’s why sharks are such fast swimmers.

[Jaws theme]

Stethacanthidae was a family of fish that went extinct around 300 million years ago. It was related to ratfish and their relatives, including sharks. Stethacanthus is the most well-known of the stethacanthidae. It grew a little over 2 feet long, or 70 cm, and was probably a bottom-dwelling fish that lived in shallow waters. It ate crustaceans, small fish, cephalopods, and other small animals.

We have some good fossils of various species of Stethacanthidae and they show one feature that didn’t get passed down to modern ratfish or sharks. That’s the shape of its first dorsal fin, the one that in shark movies cuts through the water just before something awful happens.

[Jaws theme again]

Stethacanthidae’s dorsal fin was really weird. It was shaped sort of like a scrub brush on a pedestal, with the bristles sticking upwards, which is sometimes referred to as a spine-brush complex. Researchers aren’t sure why its fin was shaped in such a way, but since it appears that only males had the oddly shaped fin, it was probably for display. It also had a patch of the same kind of short bristly denticles on its head. Males also had a long spine that grew from each pectoral fin that was probably also for display. Some researchers think the males fought each other by pushing head to head, possibly helped by the odd-shaped dorsal fin.

In the past, before researchers figured out that only the males had the strange dorsal fin, some people suggested that the fish may have used the fin as a sucker pad to attach to other, larger fish and hitch a ride. This is what remoras do. Remoras have a modified dorsal fin that is oval-shaped and acts like a sucker. The oval contains flexible membranes that the remora can raise or lower to create suction. The remora attaches to a larger animal like a shark, a whale, or a turtle and lets the animal carry it around. In return, the remora eats parasites from the host animal’s skin. But remoras aren’t related to sharks.

Other shark relatives had dorsal spines. Falcatus falcatus lived about the same time as Stethacanthus, around 325 million years ago. It grew up to a foot long, or 30 cm, and ate shrimp, fish, and other small animals. We have so many fossils of falcatus from the Bear Gulch Limestone deposits in Montana that we know quite a bit about it. It probably detected prey with electroreceptors on its snout like many modern sharks do, and it was probably a fast swimmer that could dive deeply. Its eyes are unusually large for a shark too. Females would have looked like a small, slender sharklike fish, but males had a spine that grew forward from just behind its head, sort of like a single bull’s horn. It’s called a dorsal spine and is actually a modified dorsal fin. It was probably for display, although males may have also used it to fight each other. We have a well preserved fossil of a pair of falcatus together, a male and female, where it looks like the female may be biting the male’s dorsal spine. Some researchers suggest the spine was used in a pre-mating ritual, but it’s probable that the fish just happened to die next to each other and no one was actually biting anyone.

Another shark relative with a dorsal spine is Hybodus, which grew up to 6 ½ feet long, or 2 meters. Hybodus was a successful genus of cartilaginous fish that lived from around 260 million years ago up to 66 million years ago. Researchers think its dorsal spine was used for defense since both males and females had the spine. Hybodus would have looked like a shark but its mouth was relatively small. It probably ate small fish and squid, catching them with the sharp teeth in the front of its mouth, but it also probably ate a lot of crustaceans and shellfish, which it crushed with the flatter teeth in the rear of its mouth.

Xenacanthus had a dorsal spine too, but it was a much different shark ancestor from the ones we’ve talked about so far. It lived until about 208 million years ago in fresh water. It grew to about three feet long, or one meter, and would have looked more like an eel than a shark. It was slender with an elongated body, and its dorsal fin was short but extended along the back down to the pointed tail. This suggests it probably swam like an eel, since eels have a similar fin structure. It probably ate crustaceans and other small animals.

Xenacanthus’s spine grew from the back of the skull and, unusually for a shark relation, it was made of bone instead of cartilage. Both males and females had the spine and some researchers suggest that it may have been venomous like a sting ray’s tail spine.

Rays are closely related to sharks, and if you want to see a fish that makes every single weird extinct shark look normal, just look at a sawfish. The sawfish is a type of ray and it’s alive today, although it’s endangered. I’m going to do a whole episode on rays pretty soon so I won’t go into detail, but the sawfish isn’t the only fish alive today with a long snout with teeth that stick out on either side. The sawshark is related to the sawfish but is actually a shark, not a ray. And there’s a third type of fish with a saw, related to both sawfish and sawsharks, called the Sclerorhynchidae. Sclerorhynchids went extinct around 55 million years ago and are considered part of the ray family, although they’re not ancestors of living rays. Sclerorhynchids grew around three feet long, or about a meter, and probably looked a lot like modern sawfish although with a rostrum, or snout, that was more pointed and less broad than most sawfish rostrums. The teeth that stuck out to either side were also relatively small. Researchers think Sclerorhynchids used their saws the same way modern sawfish and sawsharks do, to find small animals living on or near the bottom in shallow water and slash them to death before eating the pieces.

[Jaws theme again]

Most of the shark relatives we’ve talked about so far were pretty small, certainly compared to sharks like the great white or megalodon, which by the way we covered in episode 15 along with the hammerhead shark. But a shark called Ptychodus grew up to 33 feet long, or ten meters. It went extinct about 85 million years ago. Its dorsal fin had serrated spines and its mouth had lots and lots of really big teeth–up to 550 teeth, but they weren’t sharp. Instead, they were flattened with riblike folds that helped Ptychodus crush the mollusks it ate. It probably also ate squid and crustaceans, along with any carrion it might come across. It lived at the bottom of the ocean, but in relatively shallow areas where there were plenty of mollusks but not too many mosasaurs or other sharks that might treat Ptychodus as a nice big meal.

In episode 33, the one about dunkleosteus, we also talked about helicoprion and some of its relations. Helicoprion looked like a shark but was actually less closely related to true sharks than to ratfish. Helicoprion lived until about 250 million years ago and some researchers estimate it could grow up to 24 feet long, or 7.5 meters.

Instead of a weird dorsal fin, helicoprion had weird teeth. Weird, weird teeth. It had a tooth whorl instead of the regular arrangement of teeth, where its teeth grew in a spiral that seems to have been situated in the lower jaw. It looked like the blade of a circular saw. Now, this is bizarre but it’s not really all that much more bizarre than sawfish teeth, which aren’t even inside the mouth and stick out sideways. But the frustrating thing for researchers is that we still don’t have any helicoprion fossils except for the teeth whorls and part of one skull. Like most sharks and shark relatives, almost all of helicoprion’s skeleton was made of cartilage, not bone, and cartilage doesn’t fossilize very well. So even though helicoprion was widespread and even survived the Permian-Triassic extinction event, we don’t know what it looked like or what it ate or how exactly its tooth whorl worked. But I think it’s safe to say that it would not be good to be bitten by helicoprion.

[stop playing the Jaws theme omg]

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

[Jaws theme again]

Episode 114: The Depths of the Sea of Cortez

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The Gulf of California, AKA the Sea of Cortez, is home to thousands upon thousands of animals, many of them not found anywhere else in the world. New research expeditions in its deep-sea fissures and trenches have turned up some amazing new animals too. Let’s take a look at a few of them!

Thanks to Hally for this week’s topic suggestion!

The lollipop catshark sounds cuter than it is:

The black brotula:

A super creepy grenadier fish. Look at those EYES:

A type of batfish. It uses its stiff fins to walk around on the bottom of the ocean:

Some beautiful hydrothermal chimneys:

Giant tube worms:

Show transcript:

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

It’s been a while since we did a deep-sea episode. This week let’s find out about some strange fish discovered in the Pacific Ocean off the coast of Mexico. Thanks to Hally for the suggestion!

The Gulf of California, also called the Sea of Cortez, is the stretch of water between mainland Mexico and the Baja peninsula. Researchers estimate it started forming over 5 million years ago when tectonic forces separated the strip of land now called Baja peninsula or Baja California from the mainland. It’s still attached to the mainland at its northern edge, where the Colorado River empties into the gulf. The sea is about 700 miles wide, or over 1100 km.

Because the gulf was formed by tectonic forces and undersea volcanos, parts of it are extremely deep—more than 12,500 feet deep in places, or 3,800 meters. It’s full of islands, nearly 1,000 of them, a few of them quite large and some just tiny, some of them volcanic and some not. And it’s rich in ocean life, with many animals found in the Gulf of California that live nowhere else in the world.

For instance, the lollipop catshark! What a cute name. It probably plays ukulele and its best friend plays the xylophone. They should start a band!

The lollipop catshark is actually not super cute, although it is pretty awesome. It’s a small shark, only about 11 inches long, or 28 cm, and it has pinkish gray skin that’s almost gelatinous in texture, although it also has tiny spiky denticles, especially on its back. It gets the name lollipop from its shape. It has a broad head with large gills, but its body tapers to a slender tail so that it’s sort of shaped like a tadpole. Not really lollipop shaped, frankly. Babies are born live instead of hatching from eggs, with a female giving birth to two babies at a time. It eats crustaceans and fish.

The reason the lollipop catshark has such big gills is that it lives at the bottom of the ocean where there’s not much oxygen. The Gulf of California is especially oxygen-poor in its deepest areas, so when a team of scientists sent a submersible to the deepest parts of the gulf in 2015, they didn’t expect to find that many fish or other animals. But not only were there a lot of lollipop catsharks, there were lots of other animals too.

The submersible found the most fish in a part of the gulf called the Carralvo Trough, which is nearly 3,300 feet deep, or 1,000 meters. A few years before, a submersible had discovered the bodies of dozens of dead squid in the trough, and researchers determined that the squid were all females that had laid eggs and then died and sunk to the bottom. The dead squid are usually eaten by scavengers within 24 hours of dying, including crabs and sea stars, brittle stars, and acorn worms, as well as small bottom-dwelling sharks like the lollipop catshark. So it was good timing that the submersible saw so many of them at once.

Another deep-sea animal found in the Gulf of California is the cusk eel. There are lots of species of cusk eel that live throughout the world’s oceans and even some fresh water, and despite the name, cusk eels are fish, not eels. They’re related to cod, although not closely. They live on the bottom of the ocean, usually in shallow water, where they burrow in the sediment and sand at the bottom.

But the cusk eel found in the Carralvo Trough is called the black brotula, and it’s so different from other cusk eels that it has its own genus. The black brotula grows up to 10 inches long, or about 25 cm, and only lives in the depths of the Gulf of California and in some deep areas along the western coast of Mexico and Chile. Not only can it tolerate low-oxygen water, it prefers it. It’s black or dark gray in color–even its intestines are black. And that’s pretty much all we know about it at this point. Cusk eels are generally not very well studied, and the black brotula is hard to study because it lives so deep in the gulf. Researchers don’t even know how it tolerates water with so little oxygen and what it eats down there. We do know that young black brotulas prefer shallower water.

Another deep-sea fish found in the Gulf of California is the grenadier [grin-a-deer]. Grenadiers are some of the most common deep-sea fish in the world, with lots of different species. Some researchers estimate that they may make up as much as 15% of all fish that live in the deep sea. All grendadiers have large heads with big eyes and mouths, slender bodies that taper to such a thin tail that some people call the fish rattail.

The grenadier has barbels under the chin with chemoreceptors on them, and more chemoreceptors on the mouth and head, so it can sense other fish nearby even if it can’t see them. It’s been found as deep as nearly 23,000 feet under the surface, or 7,000 meters, which is just ridiculous. That’s four and a third miles underwater, or seven km. The Gulf of California isn’t that deep, of course, but there are grenadiers swimming around in the deepest areas, eating anything they can catch.

Some grenadiers are eaten, but mostly they have a soft, unpleasant texture and are low in protein. The biggest grenadier, which is common throughout the deep areas of the Pacific Ocean, is the giant grenadier, which can grow to 6 ½ feet long, or 2 meters. It eats vampire squid and other cephalopods. The grenadier most commonly found in the Gulf of California is the smooth grenadier, which only grows to about a foot long, or 30 cm.

A type of batfish that’s common off the western coasts of North, Central, and South America is also found in the deep sea of the Gulf of California. It’s a small type of anglerfish, only about six inches long, or 15 cm, dark in color, with a broad flattened head tapering to a much thinner long tail. Like other anglerfish, it has strong, stiff fins that it uses to crawl around on the ocean floor, where it hunts small animals like polychaete worms and crustaceans as well as fish.

If you look at the pictures I have in the show notes, or if you’ve been paying attention to the descriptions of all these fish, you’ll notice that even though they’re not related, they all share similar features. Their heads are large and usually broad, while their bodies are relatively small with a slender tail. The large head allows the fish to have unusually large gills and eyes, with a broad mouth so it can gulp down any food it finds. You know what this points to? That’s right, convergent evolution, where the fish all share a similar habitat that has influenced certain aspects of the body shape!

Currently, researchers are exploring volcanic vents in the Gulf of California that are the deepest found in the area. The area contains hydrothermal vents, which can heat the water to over 660 degrees F, or 350 degrees Celcius, and cold seeps, which are only called cold because they’re not super heated.

The vents are surrounded by mineral towers called hydrothermal chimneys that are up to 120 feet high, or 37 meters. These deepest vents and chimneys were only discovered in 2015, with others nearby only discovered in 2012. There are two types of chimneys in the area, dark-colored ones that grow the biggest, which are made up of sulfide minerals, and smaller, more delicate ones made up of light-colored carbonate minerals. The only other carbonate chimneys ever found are in the Atlantic. They’re really pretty.

Between the super heated water, the high levels of sulfides and heavy metals from the vents, and the great depth, the area would kill most animal life. But hydrothermal ecosystems are home to extremophiles that thrive in places that are deadly to other animals. The dark-colored chimneys, often called black smokers since they give off plumes of superheated minerals that look like smoke, are home to giant tube worms that can grow nearly eight feet long, or 2.4 meters, although they’re only a little more than an inch and a half wide, or 4 cm.

Giant tube worms don’t have a digestive tract, just a sort of internal pouch to hold the chemosynthetic bacteria that provide nutrients to the worm. The worm gives the bacteria a safe place to live, and the bacteria convert the carbon dioxide, hydrogen sulfide, and other minerals into nutrients that the worm absorbs.

But how do giant tube worms find new hydrothermal vents? Old vents go cold and new ones open up all the time, and giant tube worms can’t move once they’ve attached themselves to a rock or other solid structure. It turns out that newly hatched giant tube worms are free-swimming larvae, and at first they don’t contain any of the symbiotic bacteria that they need later in life. They acquire the bacteria later, when bacteria in the water find the larva and burrow into its skin. The larva swims deeper into the ocean and finds a hydrothermal vent, if it’s lucky, and attaches itself to a rock or something nearby. It then develops rapidly from a larva into the juvenile stage, where its digestive system reforms into a place for the bacteria to live. Then it grows into an adult tube worm.

The carbonate chimneys have a different kind of tube worm that prefers a different range of minerals.

Giant tube worms were only discovered in 1977. No one back then dreamed that anything could live around hydrothermal vents so the team exploring some vents hadn’t even brought along a biologist, just geologists. I like to think that they freaked out when they saw tube worms and other animals living around the vents.

It just goes to show, like they say in Jurassic Park, life finds a way.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. We also have a Patreon if you’d like to support us that way.

Thanks for listening!

Episode 087: Globsters

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It’s October! Let the spooky monster episodes begin! This week we’re starting off with a bang–or maybe a squoosh–with an episode about globsters. What are they? Why do they look like that? Do they smell?

Yes, they smell. They smell so bad.

Trunko, a globster found in South Africa:

A whale shark:

The business end of a whale shark:

A globster found in Chile:

A globster found in North Carolina after a hurricane:

A globster that still contains bones:

Not precisely a globster but I was only a few weeks late in my 2012 visit to Folly Beach to see this thing:

Further reading:

Hunting Monsters by Darren Naish

Show transcript:

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

It’s October, and you know what that means! Monsters! …and have I got a creepy monster for you this week. Grab your Halloween candy and a flashlight while I tell you about something called a globster.

If you live near the seashore, or really if you’ve spent any time at all on the beach, you’ll know that stuff washes ashore all the time. You know, normal stuff like jellyfish that can sting you even though they’re dead, pieces of debris that look an awful lot like they’re from shipwrecks, and the occasional solitary shoe with a skeleton foot inside. But sometimes things wash ashore that are definitely weird. Things like globsters.

A globster is the term for a decayed animal carcass that can’t be identified without special study. Globsters often look like big hairy blobs, and are usually white or pale gray or pink in color. Some don’t have bones, but some do. Some still have flippers or other features, although they’re usually so decayed that it’s hard to tell what they really are. And they’re often really big.

Let’s start with three accounts of some of the most famous globsters, and then we’ll discuss what globsters might be and why they look the way they do.

The St. Augustine monster was found by two boys bicycling on Anastasia Island off the coast of Florida in November 1896. It was partially buried in sand, but after the boys reported their finding, people who came to examine it eventually dug the sand away from the carcass. It was 21 feet long, or almost 6.5 meters, 7 feet wide, or just over 2 meters, and at its tallest point, was 6 feet tall, or 1.8 meters. Basically, though, it was just a huge pale pink lump with stumpy protrusions along the sides.

A local doctor, DeWitt Webb, was one of the first people to examine the carcass. He thought it might be the rotten remains of a gigantic octopus and described the flesh as being rubbery and very difficult to cut. Another witness said that pieces of what he took to be parts of the tentacles were also strewn along the beach, separated from the carcass itself.

Dr. Webb sent photographs and notes to a cephalopod expert at Yale, Addison Verrill. He at first thought it might be a squid, but later changed his mind and decided it must be an octopus of enormous proportions—with arms up to 100 feet in length, or over 30 meters.

In January a storm washed the carcass out to sea, but the next tide pushed it back to shore two miles away. Webb sent samples to Verrill, who examined them and decided it was more likely the remains of a sperm whale than a cephalopod.

In 1924, off the coast of South Africa, witnesses saw a couple of orcas apparently fighting a huge white monster covered with long hair—far bigger than a polar bear. It had an appendage on the front that looked like a short elephant trunk. Witnesses said the animal slapped at the orcas with its tail and sometimes reared up out of the water. This went on for three hours.

The battle was evidently too much for the monster, and its corpse washed ashore the next day. It measured 47 feet long in all, or 14.3 meters, and the body was five feet high at its thickest, or 1.5 meters. Its tail was ten feet long, or over three meters, and its trunk was five feet long and over a foot thick, or about 35 cm. It had no legs or flippers. But the oddest thing was that it didn’t seem to have a head either, and there was no blood on the fur or signs of fresh wounds on the carcass.

The carcass was so heavy that a team of 32 oxen couldn’t move it. The reason someone tried to move it was because it stank, and the longer it lay on the beach the more it smelled.

Despite its extraordinary appearance, no scientists came to investigate. After ten days, the tide carried it back out to sea and no one saw it again. Zoologist Karl Shuker has dubbed it Trunko and has written about it in several of his books.

Another globster was discovered well above ordinary high tide on a Tasmanian beach in 1960 after a massive storm. It was 20 feet long, or 6 meters, 18 feet wide, or 5.5 meters, and about 4 ½ feet high at its thickest, or 1.4 meters. It stayed on the beach for at least two years without anyone being especially interested in it. It was in a fairly remote area, admittedly. It wasn’t until 1962 that a team of zoologists examined it. They reported that it was ivory-colored, incredibly tough, boneless, and without any visible eyes. The lump had four large lobes, but it also appeared to have gill slits. One of the zoologists suggested it might be an enormous stingray.

So what were these three globsters?

Let’s look at Trunko first. Shuker points out that when a shark decomposes, it can take on a hairy appearance due to exposed connective tissue fibers. But Trunko was fighting two orcas only hours before it washed ashore.

OR WAS IT??

Here’s the thing. No one saw the fight from up close and orcas are well known to play with their food. There’s a very good chance that Trunko was already long dead and that the orcas came across it and batted it around in a monstrous game of water volleyball. That would also explain why there was no blood associated with the corpse.

In that case, was Trunko a dead shark? At nearly 50 feet long, it would have had to be the biggest shark alive…and as it happens, there is a shark that can reach that length. It’s called the whale shark, which tops out at around 46 feet, or 14 meters, although we do have unverified reports of individuals nearly 60 feet long, or 18 meters—or even longer.

Like the megamouth shark, the whale shark is a filter feeder and its mouth is enormous, some five feet wide, or 1.5 meters. But the interior of its throat is barely big enough to swallow a fish. Its teeth are tiny and useless. Instead, it has sieve-like filter pads that it uses to filter tiny plants and animals from the water, including krill, fish eggs and larvae, small fish, and copepods. The filter pads are black and are probably modified gill rakers. The whale shark either gulps in water or swims forward with its mouth open, and water flows over the filter pads before flowing out through the gills. Tiny animals are directed toward the throat so the shark can swallow them.

The whale shark is gray with light yellow or white spots and stripes, and three ridges along each side. Its sandpaper-like skin is up to four inches thick, or 10 cm. It has thick, rounded fins, especially its dorsal fin, and small eyes that point slightly downward. It usually stays near the surface but it can dive deeply too, and it’s a fast swimmer despite its size. Females give birth to live babies which are a couple of feet long at birth, or 60 cm. While no one has watched a whale shark give birth, researchers think a shark may be pregnant with hundreds of babies at a time, but they mature at different rates and only a few are born at once.

The whale shark isn’t dangerous to humans at all, but humans are dangerous to whale sharks. It’s a protected species, but poachers kill it for its fins, skin, and oil.

The whale shark usually lives in warm water, especially in the tropics, but occasionally one is spotted in cooler areas. They’re well known off the coast of South Africa. If the Trunko globster was a dead whale shark, the “trunk” was probably the tapered end of the tail, with the flukes torn or rotted off. Most likely the jaws had rotted off as well, leaving no sign that the animal had a head or even which end the head should be on.

But sharks aren’t the only big animals in the ocean, and the skin and blubber of a dead whale can also appear furry once it’s broken down sufficiently due to the collagen fibers within it. Collagen is a connective tissue and it’s incredibly tough. It can take years to decay. Tendons, ligaments, and cartilage are mostly collagen, as are bones and blubber.

While we don’t know what Trunko really was, many other globsters that have washed ashore in modern times have been DNA tested and found to be whales. In 1990 the Hebrides blob washed ashore in Scotland. It was 12 feet long, or 3.7 meters, and appeared furry, with a small head at one end and finlike shapes along its back. Despite its weird appearance, DNA analysis revealed it was a sperm whale, or at least part of one. Another sperm whale revealed by DNA testing was the Chilean blob, which washed ashore in Los Muermos, Chile in 2003. It was 39 feet long, or 12 meters.

As for the tissue samples of the St Augustine monster, they still exist, and they’ve been studied by a number of different people with conflicting results. In 1971, a cell biologist from the University of Florida reported that it might be from an octopus. Cryptozoologist Roy Mackal, who was also a biochemist, examined the samples in 1986 and also thought the animal was probably an octopus. A more sophisticated 1995 analysis published in the Biological Bulletin reported that the samples were collagen from a warm-blooded vertebrate—in other words, probably a whale. The same biologist who led the 1995 analysis, Sidney Pierce, followed up in 2004 with DNA and electron microscope analyses of all the globster samples he could find. Almost all of them turned out to be remains of whale carcasses, of various different species. This included the Tasmanian globster.

Sometimes a globster is pretty obviously a whale, but one with a bizarre and unsettling appearance. The Glacier Island globster of 1930, for instance, was found floating in Eagle Bay in Alaska, surrounded by icebergs from the nearby Columbia Glacier. The head and tail were skeletal, but the rest of the body still had flesh on it, although it appeared to be covered with white fur. Its head was flattish and triangular and the tail was long. The men who found the carcass thought it had been frozen in the glacier’s ice.

They hacked the remaining flesh off to use as fishing bait, but they saved the skeleton. A small expedition of foresters came to examine the skeleton, which they measured at 24 feet and one inch, or over 7.3 meters. They identified it as a minke whale. The skeleton was eventually mounted and put on display in a traveling show, advertised as a prehistoric monster found frozen in a glacier. In 1931 the skeleton was donated to the National Museum of Natural History in Washington DC, where it remains in storage. Modern examinations confirm that it’s a minke whale.

On March 22, 2012, a rotting corpse 15 feet long, or 4.6 meters, with armor-like scutes along the length of its body, washed ashore on Folly Beach in South Carolina. This isn’t exactly a globster, since it was still fish-shaped, but I’m including it because I was literally at Folly Beach a matter of weeks after this thing washed ashore. I wish I’d seen it. It turned out that it wasn’t a sea monster as people assumed, but a rare Atlantic sturgeon.

Many globsters have stumps that look like the remains of flippers, legs, or tentacles. The Four Mile Globster that washed ashore on Four Mile Beach, Tasmania in 1998 had protrusions along its sides that looked like stumpy legs. It was 15 feet long, or 4.6 meters, and 6 feet wide, or 1.8 meters, with white hair and flippers that were separate from the protrusions. We don’t actually know for sure what this globster was.

In 1988 a treasure hunter found a globster now called the Bermuda blob. It was about eight feet long, or almost 2.5 meters, pale and hairy with what seemed to be five legs. The discoverer took samples of the massively tough hide, which were examined by Sidney Pierce in his team’s 1995 study of globster remains. This was one of the few that turned out to be from a shark instead of a whale, although we don’t know what species.

But sharks don’t have five legs. And the Four Mile Globster had six stumps that were separate from the flippers still visible on the carcass. So what causes these leg-like protrusions? They’re probably flesh and blubber stiffened inside with a bone or part of a bone, such as a rib. As the carcass is washed around by the ocean, the flesh tears in between the bones, making them look like stumps of appendages.

There’s a good reason why so many globsters turn out to be sperm whale carcasses. A sperm whale’s massive forehead is filled with waxy spermaceti oil. The upper portion of the head contains up to 500 gallons of oil in a cavity surrounded by tough collagen walls. Researchers hypothesize that this oil is used both for buoyancy and to increase the whale’s echolocation abilities. The lower portion of the forehead contains cartilage compartments filled with more oil, which may act as a shock absorber since males in particular ram each other when they fight. So much of the head of a sperm whale, which can be as big as 1/3 of the length of the whale, is basically a big mass of cartilage and connective tissue. After a whale dies, this buoyant section of the body can separate from the much heavier skeleton and float away on its own.

Globsters aren’t a modern phenomenon, either. We have written accounts of what were probably globsters dating back to the 16th century, and older oral traditions from folklore around the world. The main problem with globsters is that they’re not usually studied. They smell bad, they look gross, and they may not stay on the beach for long before the tide washes them back out to sea. For instance, after Hurricane Fran passed through North Carolina in 1996, a group of young men found a globster washed up on a beach on Cape Hatteras. They took pictures and estimated its length as twenty feet long, or six meters, six feet wide, or 1.8 meters, and four feet high at its thickest, or 1.2 meters. From the pictures it’s pretty disgusting, like a lump of meat with intestines or tentacles hanging from it. But the men weren’t supposed to be on the beach, which was part of the Cape Hatteras National Park and closed due to hurricane damage. They didn’t mention their find to anyone until the following year, when one of the men learned about the St Augustine Monster in his college biology class. By then, of course, the Cape Hatteras globster was long gone. While it might have been a rotting blob of whale blubber or a piece of dead shark, we don’t know for sure. So if you happen to find a globster on a beach, make sure to tell a biologist or park ranger so they can examine it…before it’s lost to science forever.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. 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

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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:

THAT EYEBALL:

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 strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. 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!