Category Archives: North America

Episode 425 Rabbits!

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Thanks to Alyx and Richard from NC for their suggestions this week! Let’s learn about rabbits!

Further reading:

Why your pet rabbit is more docile than its wild relative

FOUND: Small enigmatic rabbit with black tail lost to science for more than 120 years rediscovered hopping around mountain range in Mexico

The Omiltemi cottontail rabbit, as caught on a camera trap [photo taken from second article linked above]:

Show transcript:

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

This week we’re going to talk about bunnies, and also learn about how a wild animal differs from its domesticated counterpart. Thanks to Alyx for suggesting this excellent topic. Thanks also to Richard from NC who alerted me to a rediscovered rabbit we’ll discuss too.

Thanks for all the well wishes in the last few weeks about my surgery. It went just fine and all I have now is a cool-looking new scar, although I was seriously hoarse for about a week. It’s pretty weather here in East Tennessee and officially it’s spring in the northern hemisphere, so let’s talk about some springtime bunnies!

Collectively rabbits and hares are called leporids after their family, Leporidae. Leporids are famous for hopping instead of walking, and they’re able to do so because their hind legs are longer than their front legs and have specialized ankle joints. Ancestors of leporids developed this ankle as much as 53 million years ago, but their legs were much shorter so they probably ran instead of hopped. Hares have longer legs than rabbits and can run faster as a result, but both rabbits and hares are known for their ability to bound at high speeds. When a rabbit or hare runs, it pushes off from the ground with the tips of its long hind toes, and its toes are connected with webbed skin so they can’t spread apart. If the toes did spread apart, they would be more likely to get injured. Rabbits and hares also don’t have paw pads like dogs and cats do. The bottom of its foot is covered with dense, coarse fur that protects the toes from injury. Its long claws help it get a good purchase on the ground so its feet won’t slip.

Leporids eat plants, including grass, weeds, twigs, and bark. Animals that eat grass and other tough plants have specialized digestive systems so they can extract as many nutrients from the plants as possible. Many animals swallow the plants, digest them for a while, then bring up cuds of plants and water to chew more thoroughly. Rabbits and hares don’t chew their cud in that way, but they do have a system that allows them to twice-digest the plants they eat.

After a leporid eats some plants, the plant pieces go into the stomach, naturally, and then travel into the first part of the large intestine, called the cecum. The cecum separates the softer parts of the plants from the harder, less digestible parts. The hard parts are compressed into hard pellets that the rabbit poops out. But the soft parts of the plants, which are most nutritious, develop into softer pellets. These are called cecotropes, and as soon as the rabbit poops out the cecotropes, it immediately eats them again. This allows the digestive system to get a second round to extract more nutrients from the plants.

Hares aren’t domesticated, but rabbits have probably been domesticated many times in different places over the last several thousand years, first for food and fur, and then as pets. The domesticated rabbit we have today is descended from the European rabbit, also called the cony. If other species of rabbit were ever domesticated, we don’t have record of it. The rabbit has also been introduced into the wild in places it has no business to be, like Australia, where it’s an invasive species. You know where else the European rabbit has been introduced? The British Isles. It’s native to mainland Europe, not England, Scotland, Ireland, Wales, and smaller islands nearby. Historians think the rabbit was introduced to England soon after the year 1066, but it got really common a few hundred years later.

We discussed domestication way back in episode 106, mostly in relation to dogs. An interesting thing happens with domestication. Certain physical traits come along with the behavioral traits of reduced aggression and willingness to treat humans as surrogate parents. In the case of dogs, these often include a puppy-like appearance, including floppy ears, curled tail, smaller adult size, and a rounder head with smaller jaws. White patches of fur start to show up too.

This is true in rabbits as well as dogs. Because humans wanted to breed rabbits that weren’t scared of people, domesticated rabbits are less anxious and aggressive in general than their wild counterparts. When traits like white patches, lop ears, and a more rounded face appeared in the domesticated population, people would keep those rabbits to breed because they’re extra cute, which has led to over three hundred different breeds recognized today by rabbit enthusiasts.

Because domesticated rabbits are calmer and more trusting than wild rabbits, they can’t survive long in the wild. A domesticated rabbit doesn’t know how to escape from predators or avoid cars, and it’s not used to cold weather. If you decide to adopt a bunny, make sure you do research ahead of time to know what to expect, and as with most animals it’s best to adopt two so they won’t be lonely. Rabbits are social animals and need a rabbit friend. There are even pet rescues that specialize in rabbits who need homes.

We talked about giant rabbits in episode 115, and the tiny volcano rabbit in episode 356, so let’s finish this episode with a medium-sized rabbit called the Omiltemi cottontail. Cottontail rabbits are native to the Americas and most have fluffy white fur on the underside of their tails. The Omiltemi cottontail doesn’t have any white fur at all, and is reddish-brown and black in color with some lighter gray on its face. It’s large for a wild rabbit, about 18 inches long, or 45 cm, although it’s actually smaller than other rabbits that live in the area. It lives only in Mexico, specifically in a single part of the Sierra Madre del Sur mountain range, in what is now the Omiltemi Ecological State Park.

It was first described in 1904 and then reportedly wasn’t seen again, although the local people knew all about it. Even though it lives in a protected area, poaching is still a big problem. When an expedition to find the rabbit got underway in 2019, local hunters provided pelts to the scientists when they asked about the rabbit, since they didn’t know they weren’t supposed to kill the local rabbits. They certainly didn’t know they had an incredibly rare species of rabbit living in their back yards.

The team used camera traps, drone surveys, and the knowledge of local people to find and identify the Omiltemi cottontail. It turns out that the rabbit is mostly nocturnal and prefers higher elevations, which made it harder to find. We still don’t know how many there are left, but now that scientists are certain that it’s not extinct, it can be better protected.

You can find Strange Animals Podcast 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 for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 424 Old-Timey Giant Snakes

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Show transcript:

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

Recently I read about a giant snake supposedly seen in Tennessee in 1908. The story seemed a little suspicious so I dug into it, and it got a lot more complicated than I expected.

On July 25, 1908, the St. Louis (Missouri) Globe-Democrat ran an article about a giant snake in Loudon, Tennessee. Loudon is a town half an hour’s drive away from Knoxville in East Tennessee, although it took longer to get there from Knoxville in 1908. According to the article, the snake was “at least twenty-five feet in length, eight inches in diameter and twenty-four inches in circumference.”

The longest snake ever reliably measured is a reticulated python named Medusa, who was measured as 25 feet 2 inches long in 2011, or 7.67 meters. Medusa holds the world record for the longest snake in captivity. Reticulated pythons are constrictors, which are non-venomous snakes who kill their prey by squeezing them until blood flow is shut off to the organs, causing cardiac arrest and death. As a result, they’re incredibly strong snakes. The reticulated python is native to southern Asia and not likely to be found running loose in East Tennessee even today, and certainly not in 1908.

The famous Boa constrictor and other snakes in the genus Boa are all native to Central and South America, while the closely related anaconda is from tropical South America. These snakes are also constrictors.

The anaconda is rumored to grow over 30 feet long, or 9 meters, although the longest specimen ever reliably measured was 17 feet long, or 5.2 meters. Since snake skin is stretchy, though, preserved skins of huge size are often provided as proof of snakes much longer than the known maximum. While the anaconda isn’t as long as the reticulated python, it’s much bulkier, so a 25-foot anaconda would be much heavier and larger around than a 25-foot reticulated python.

The 1908 article claims that the snake “has been seen off and on for the last twenty-eight years, but not until this summer has it caused any serious alarm.” I don’t know about you, but even as someone who likes animals and thinks snakes are neat, if I saw a 25-foot snake I would be a little bit alarmed even if it wasn’t doing anything. The article then describes how the snake had knocked down a fence while climbing over it and that it had taken a lamb. One man even managed to shoot the snake, although only with “small shot,” and the article claims that the snake, “in a frenzy from the pain, tore up saplings in getting away.”

The article finishes by reporting that women and children were barricaded in their homes while men organized a posse to hunt down the giant snake, which was rumored to live in a cave overlooking the river.

The same article ran in various newspapers around the country for months, but there was no follow-up to let readers know if the snake had been found. But the story didn’t appear in any Tennessee newspapers.

The only 1908 article about a giant snake in Tennessee that appears in a Tennessee newspaper is from August 21. The Chattanooga, Tennessee Daily Times reported that a blacksnake “fully six feet long and two inches in diameter” had been spotted eating young pigeons above the Birmingham railway station. A police officer shot and killed it, but its body couldn’t be recovered from the steep hillside above the tunnel.

“Blacksnake” is a term used for two snakes that are common throughout the southern United States: the eastern black kingsnake and the North American racer. Both are black in color and can grow more than 6 feet long, or 1.8 meters. Both are non-venomous and eat small animals like mice, frogs, and lizards, while the kingsnake also sometimes eats other snakes.

The longest snake found in Tennessee, which also lives throughout much of eastern North America, is the gray ratsnake, which is frequently 6 feet long and sometimes longer. One unverified report of a captive snake 8 feet 10 inches long, or almost 2.5 meters, comes from Tennessee. It’s a mixture of dark and light gray with a lighter belly. It’s non-venomous and is actually a constrictor, although it’s not dangerous to humans. If it feels threatened, it will sometimes pretend to strike and rattle the tip of its tail against dead leaves or whatever else might be underneath it, which produces a buzzing sound that mimics a rattlesnake’s rattle. You’re not fooling anyone, gray ratsnake.

The eastern racer will also vibrate its tail against leaves to imitate a rattlesnake’s rattle, but the eastern racer is such a fast-moving snake that it doesn’t usually need to convince potential predators it’s dangerous. It just runs away. Despite its name of Coluber constrictor, it’s not actually a constrictor, although it will pin an animal to the ground with its body until it can swallow it whole. It and the gray ratsnake can both climb trees and will eat bird eggs and young birds when they find them.

There is another article about a giant snake in a Tennessee newspaper from 1908. The Chattanooga Star reported on August 20 that a 12-foot, or 3.6 meter, rattlesnake was attacked by a boar when it tried to enter a hog pen. The farmer managed to shoot the snake, which had 29 rattles. The snake was referred to as “Big Jim” in the area. But that story was supposed to have happened in Sullivan, Indiana, not in Tennessee.

But Indiana newspapers don’t run this account. A July 22, 1908 article in the Indianapolis News reports that a rattlesnake with 26 rattles was killed in Nashville, Indiana, but that snake was not quite six feet long, or 1.8 meters.

The “Big Jim” account does appear in one Indiana newspaper, the Hamilton County Times from August 21, 1908. But that article is headlined “Some Hoosier ‘Nature Fakes’” and says Big Jim was first spotted in the neighboring state of Illinois but had been discovered attacking a farmer’s chickens in Sullivan County, Indiana. This must be the same as Sullivan, Indiana reported in the Tennessee paper. But Big Jim was only ten feet long in the Indiana story, or 3 meters, and wasn’t killed. The article says the local farmers were organizing to hunt it down, but then goes on to talk about some other stories of huge snakes and a giant fish. It seems clear that the Indiana article is meant to be amusing, not factual.

The largest rattlesnake species is the eastern diamondback rattler, and the largest one ever reliably measured was 7.8 feet long, or 2.4 meters. That’s big, but it’s not Big Jim big. The eastern diamondback also doesn’t live anywhere near Indiana or Illinois. It’s native to the southeastern United States, especially along the coast.

Newspaper reporters weren’t always scrupulous in the olden days, sometimes making up stories to fill space and entertain the reader. Stories of huge snakes are so common in old newspaper reports that the term “snake story” was once used interchangeably with “fish story” to indicate an animal of improbable size that was supposedly spotted or killed, but without any proof.

In 1935, the Statesville (North Carolina) Record and Landmark ran an article titled “Giant Snake Story Proves To Be Hoax.” No kidding! In this case, though, the story was about a snake skin 16 feet long, or nearly 5 meters, which was supposed to be from a rattlesnake killed in a local swamp. The article revealed that the two men who claimed to have shot the rattlesnake had later confessed the skin was from a python, and had been sent to one of the men by a relative in South America. At least that one was from a real snake.

Thanks for your support, and thanks for listening!

Episode 423: Pack Rats and Busy Mice

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Further reading:

Mouse filmed moving items in man’s shed in Bristol

The pack rat:

Show transcript:

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

This week I’m sharing a Patreon episode from last year because I have surgery scheduled. Don’t worry, it’s minor thyroid surgery and I’ll be fine, but my doctor said that a side effect might be hoarseness while I recover. Rather than risk sounding like an old frog, and to allow myself lots of time to rest afterwards, I’ve scheduled Patreon episodes for this week and next week.

At the beginning of this year, in early January 2024, you may have heard about a man in Wales who had an interesting visitor to his work shed. Rodney Holbrook is 75 years old and a retired postal worker, and at the end of 2023 he started noticing something weird. Things in his work shed kept being moved, and not in a way that suggested another person was getting in.

Initially Rodney noticed that some bird food had been moved into an old pair of shoes. This wasn’t just a one-time thing that would suggest an accident, like maybe Rodney had absent-mindedly decided to store the bird food in his shoes, or maybe it just fell there. The bird food kept ending up in the shoes.

Other things kept getting moved too. Small items that Rodney had left out while making and repairing things at his work bench kept getting put into a box, like tools and nuts and bolts. It happened almost every night.

Fortunately, Rodney is also a wildlife photographer, and he just happened to have a night vision camera. He set it up in the shed to find out what on earth was going on.

A mouse was going on, that’s what was going on. This actually wasn’t a huge surprise to Rodney, because years before, in 2019, a friend of his had had the same thing happen.

His friend was Steve Mckears who lived near Bristol, England. Steve kept crushed peanuts in a tub to use as bird food, but he started to notice other things mixed in with the peanuts. First it was just one screw, then it was lots more things that he’d left around his shed. He couldn’t figure out a solution, because he always locked his shed at night.

As Steve said at the time, “I was worried. I’m 72 and you hear of things going wrong with 72-year-old gentlemen in the mind.” Fortunately, Steve’s friend Rodney set up a camera and proved that there was nothing wrong with Steve’s mind or with the shed’s lock. It was just a mouse who was tidying up.

The question is why are these mice tidying up someone else’s shed? Don’t the mice have sheds of their own to clean up? It’s probable that the mice are actually living in the sheds and are wondering why some humans keep barging in every day and making a mess.

Rodents of all kinds do tend to tidy up as part of the foraging and nesting process. Sometimes that means moving debris so the animal can find important items more easily, sometimes it means bringing items back to its nest. House mice and rats will steal small items from humans to make nests, like socks and facecloths. Some rodents are attracted to shiny things and will stash them away or even bury them.

One animal, the pack rat, is so famous for storing items that we call a person who likes to collect things a pack rat. The pack rat lives throughout much of North and Central America and is related to mice and rats. It’s bigger than a mouse but smaller than most rats, and some species have furry tails like ground squirrels. It builds a den out of whatever materials are available where it lives, and its den is complex and usually well hidden. Desert species like to build under a cactus, while others live in cliffs or among rocks, in abandoned buildings or sometimes non-abandoned buildings, under bushes, in the tops of trees, or even in the entrances to caves. The den can be quite large and contains numerous rooms used for food storage, sleeping, and storing all the interesting things the pack rat finds while foraging.

A pack rat constructs a debris pile to hide its den, referred to as a midden. “Midden” is an old-fashioned word used to describe a place where household waste used to be thrown. Archaeologists love middens because you can learn a lot about people by the things they throw away, and other scientists love pack rat middens for the same reason. Some pack rat middens have been discovered preserved for 50,000 years, which has allowed scientists to learn a lot about what plants were growing in the area at the time. Since the middens also contain the pack rat’s fecal pellets, the scientists can also learn a lot about what the rat was eating, how big it was, and so forth.

Pack rats especially like shiny objects and will steal from people. In 2017 when historians were restoring an old home in Charleston, South Carolina dating back to 1808, they discovered several old pack rat middens in the walls of the kitchen. The middens contained buttons, marbles, sewing pins, and even some scraps of paper, including bits of newspaper with a readable date from November 1833. But some of the other bits of paper were torn from a writing primer, a book for people learning how to read or write. That’s not much of a surprise until you remember that this was the early 19th century, that the house was owned by a slave trader, and that the kitchen in particular would have been staffed by enslaved people, who were not supposed to learn how to read. Thanks to the pack rats, we know that at least one person was secretly learning how to read and write. I just hope the rats didn’t do too much damage to their book.

The pack rat is also sometimes called a trader rat, because it can only carry one thing at a time. If it’s carrying an acorn home and it chances upon a shiny gold ring, it will drop the acorn and carry the ring home. But you wanted an acorn, didn’t you, instead of that ring?

As for mice tidying up, we don’t really know why they do it, but it’s probably actually quite common. It just happens at night when people aren’t around, and in the morning they don’t know why all the nails have been moved into the box of nails, but hey, isn’t that handy? It reminds me of the stories of little house spirits called brownies, which were supposed to work at night cleaning and tidying. When the family woke up the next morning, the house or workshop was, ahem, squeaky clean, and all the family had to do was leave out a little cake or cream every night for the brownie.

Thanks for your support, and thanks for listening!

Episode 413: The Great American Interchange

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Thanks to Pranav for suggesting this week’s massive topic!

Further reading:

When did the Isthmus of Panama form between North and South America?

Florida fossil porcupine solves a prickly dilemma 10-million years in the making

Evidence for butchery of giant armadillo-like mammals in Argentina 21,000 years ago

Glyptodonts were big armored mammals:

The porcupine, our big pointy friend:

Show transcript:

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

This week, at long last, we’re going to learn about the great American interchange, also called the great American biotic interchange. Pranav suggested this topic ages ago, and I’ve been wanting to cover it ever since but never have gotten around to it until now. While this episode finishes off 2024 for us, it’s the start of a new series I have planned for 2025, where every so often we’ll learn about the animals of a particular place, either a modern country or a particular time in history for a whole continent.

These days, North and South America are linked by a narrow landmass generally referred to as Central America. At its narrowest point, Central America is only about 51 miles wide, or 82 km. That’s where the Panama Canal was built so that ships could get from the Atlantic Ocean to the Pacific and vice versa without having to go all around South America.

It wasn’t all that long ago, geologically speaking, that North and South America were completely separated, and they had been separated for millions of years. South America was part of the supercontinent Gondwana, while North America was part of the supercontinent Laurasia.

We’ve talked about continental drift before, which basically means that the land we know and love on the earth today moves very, very slowly over the years. The earth’s crust, whether it’s underwater or above water, is separated into what are called continental plates, or tectonic plates. You can think of them as gigantic pieces of a broken slab of rock, all of the pieces resting on a big pile of really dense jelly. The jelly in this case is molten rock that’s moving because of its own heat and the rotation of the earth and lots of other forces. Sometimes two pieces of the slab meet and crunch together, which forms mountains as the land is forced upward, while sometimes two pieces tear apart, which forms deep rift lakes and eventually oceans. All this movement happens incredibly slowly from a human’s point of view–like, your fingernails grow faster than most continental plates move. But even if a plate only moves 5 millimeters a year, after a million years it’s traveled 5 kilometers.

Anyway, the supercontinent Gondwana was made up of plates that are now South America, Africa, Australia, Antarctica, and a few others. You can see how the east coast of South America fits up against the west coast of Africa like two puzzle pieces. Gondwana actually formed around 800 million years ago, then became part of the even bigger supercontinent Pangaea, and when Pangaea broke apart around 200 million years ago, Gondwana and Laurasia were completely separate. North America was part of Laurasia. But Gondwana continued to break apart. Africa and Australia traveled far away from South America as molten lava filled the rift areas and helped push the plates apart, forming the South Atlantic Ocean. Antarctica settled onto the south pole and India traveled past Africa until it crashed into Eurasia. By about 30 million years ago, South America was a gigantic island.

It’s easy to think that all this happened just like taking puzzle pieces apart, but it was an incredibly long, complicated process that we don’t fully understand. To explain just how complicated it is, let’s talk for a moment about marsupials.

Marsupials are mammals that are born very early and finish developing outside of the mother’s womb, usually in a special pouch. Kangaroos, wallabies, koalas, wombats, and Tasmanian devils are all marsupials, and all from Australia. But marsupials didn’t originate in Australia and are still present in other parts of the world.

The oldest known marsupial appears in North America about 65 million years ago, which was part of the other supercontinent on Earth at the same time as Gondwana, called Laurasia. About the time marsupials were spreading out across Laurasia, from North America all the way to China, Laurasia and Gondwana were connected for a while along the northern edge of South America. Animals were able to cross from Laurasia to Gondwana before the two supercontinents split apart again. Marsupials spread from Laurasia and across Gondwana before the continent of Australia separated about 50 million years ago. Marsupials did so well in Australia that researchers think that before Australia was fully separated from Gondwana, marsupials actually started spreading back out of Australia and into Gondwana again.

While marsupials were doing extremely well in Australia, in South America, birds were the dominant vertebrate for a long time. We talked about terror birds in episode 202. Phorusrhacidae is the name for a family of flightless birds that lived from about 62 million years ago to a little under 2 million years ago. They were carnivores and various species ranged in size from about 3 feet tall to 10 feet tall, or 1 to 3 meters, and had long, strong legs that made them fast runners. The terror bird also had a long, strong neck, a sharp hooked beak, and sharp talons on its toes.

Other birds in North America were likewise huge, but could fly. Those were the teratorns, which are related to modern New World vultures. Since they had huge wingspans and could fly long distances easily, they could just fly between North and South America if they wanted to, so teratorns were found on both continents starting around 25 million years ago. They only went extinct around 10,000 years ago. The largest species known, Argentavis magnificens, lived in South America around six million years ago. It’s estimated to have a wingspan of at least 20 feet, or 6 meters, and possibly as much as 26 feet, or 8 meters. That’s the size of a small aircraft.

In addition to giant predator birds, South America had crocodilians that could grow over 30 feet long, or 9 meters, and possibly as much as 40 feet long, or 12 meters. And, of course, it had ancestral forms of animals we’re familiar with today, like sloths, anteaters, armadillos, opossums, monkeys, capybaras, and lots more. Some of these were incredibly large too, like the giant ground sloth that was as big as an African elephant and the glyptodon that was related to modern armadillos. Glyptodon had a huge bony carapace and rings of bony plates on the end of its thick tail that made it into a club-like weapon, and it was the size of a car. Both the giant ground sloths and the glyptodonts were plant-eaters, as were the notoungulates.

The notoungulates are an extinct order of hoofed animals that lived throughout South America. They were probably most closely related to rhinoceroses, horses, and other odd-toed ungulates, but they’re completely extinct with no living descendants. Some were tiny and actually looked and probably acted more like rabbits than horses, while others were massive. We talked about trigodon in episode 387, and it and many of its close relations in the family Toxodontidae were the size and build of a modern rhinoceros. Trigodon even had a small horn on its forehead. A closely related group, Litopterna, is also a completely extinct order of ungulates, which were mostly smaller and more deer-like than the notoungulates.

The Pleistocene is also called the ice age, but it’s more accurate to say that it was a series of ice ages with long periods of warmer weather in between–tens of thousands of years of warmer climate, then a colder cycle that lasted tens of thousands more years. When the glaciers were at their maximum, with ice sheets covering some parts of the world over a mile thick, or a kilometer and a half, sea levels were considerably lower because so much of the world’s water was frozen solid. That exposed more land that would ordinarily be partially or completely underwater, and it also led to a dryer climate overall. At the same time, volcanic activity in the ocean separating what is now North and South America had been building up volcanic islands for millions of years. All these factors and more combined to form the Isthmus of Panama, also called Central America, that is basically a land bridge connecting the two continents.

This started around 5 million years ago and the isthmus was fully formed by about 3 million years ago, or at least that’s the most accepted theory right now. A 2016 study suggested that the land bridge started forming far earlier than that, possibly as early as 23 million years ago, possibly 6 to 15 million years. Studies are ongoing to learn more about the timeline.

What we do know is that once the land bridge opened up, animals started migrating into this new area. Animals from North America migrated south, and animals from South America migrated north. It didn’t happen all at once, of course. It was a slow process as various animal populations expanded into Central America over generations. Some animals had trouble with the climate or couldn’t find the right foods, while others did really well and expanded rapidly.

The ancestors of some animals that made it to North America and are still around include the Virginia opossum, the armadillo, and the porcupine. Meanwhile, the ancestors of llamas, horses, tapirs, deer, canids, felids, coatis, and bears traveled to South America and are still there, along with many smaller animals like rodents. Many other animals migrated, survived for a while, but later went extinct. This included a type of elephant called the gomphothere and saber-toothed cats that migrated south, while ground sloths, terror birds, glyptodonts, capybaras, and even a type of notoungulate migrated north.

You may notice that more animals that migrated south survived into modern times. South America was much warmer overall than North America, and most animals that traveled north had trouble adapting to a colder climate and competing with animals that were already well-adapted to the cold. Animals traveling south encountered warmer climates early, and if they were able to tolerate hot weather they didn’t have to worry about any climactic shocks on the rest of their journey south. As a result, North American animals were able to establish themselves in larger numbers, which helped them adapt even faster since more babies were being born and surviving.

One South America to North America success story is the porcupine. Porcupines are rodents, and there are two groups, referred to as old world and new world porcupines. Those are not great terms but that’s what we have right now. The old world porcupines are found in parts of Africa, Asia, and Italy, although they were once more widespread in Europe, while new world porcupines are found in parts of North and South America. Old world porcupines live exclusively on the ground and are larger overall than new world ones, which spend a lot of time in trees. Surprisingly, the two groups are only distantly related. They evolved spines separately. They’re also only very distantly related to hedgehogs.

The one thing everyone knows about the porcupine is that it has quills, long sharp spines that make hedgehog spines look positively modest. Porcupine quills are dangerous. They’re modified hairs, and actual hair grows in between the quills, but they’re covered in strong keratin plates and are extremely sharp. They also come out easily and regrow all the time. A porcupine can hold its spines down flat so it won’t hurt another porcupine, which is what they do when they mate.

Only one species of porcupine lives in North America, called the North American porcupine. It lives throughout much of the northern and western part of the continent, from way up in the far north of Canada down to central Mexico, although it doesn’t live in most of the southeast. We don’t know if the North American porcupine developed after South American porcupines migrated north, or if it developed much earlier, around 10 million years ago. Porcupine experts have been arguing about this for years, because there aren’t very many porcupine fossils to study.

Then a nearly complete fossil porcupine was discovered in Florida. It was such a big deal that the scientific team that discovered it decided to create an entire college course for paleontology students to help study the specimen. The resulting study was published in May of 2024, and the results suggest that the North American porcupine evolved a lot longer ago than the Isthmus of Panama formed.

The North American porcupine had to change a lot to withstand the intense cold when its ancestors were tropical animals. The North American porcupine is very different from its South American cousins. It spends less time in trees and doesn’t have a prehensile tail, it eats a lot of bark instead of mostly leaves, and it has thick insulating fur between its quills. The fossilized specimen discovered in Florida still had a prehensile tail and didn’t have the strong jaw it needed to gnaw bark off trees, but it already showed a lot of adaptations that are seen in the North American porcupine but not in South American species.

Ultimately, of course, a lot of large animals went extinct around 12,000 to 10,000 years ago, the end of the Pleistocene. Animals like mammoths that were well-adapted to cold died out as the climate warmed, and so did their predators, like dire wolves and the American lion. The notoungulates and other megaherbivores in South America went extinct too.

One animal that I haven’t mentioned yet that migrated south successfully was Homo sapiens. Maybe you’ve heard of them. Until very recently, the accepted time frame for humans migrating into South America was about 16,000 years ago, although not everyone agreed. But in July of 2024, a new study pushed that date back to 21,000 years ago.

The study examined glyptodont fossils found in what is now Argentina. The fossils were found on the banks of a river and were determined to show butchering marks from stone tools. The bones were dated to almost 21,000 years ago, which means that humans probably moved into South America a lot earlier than that. It takes time to travel from Central America down to Argentina.

One detail most people don’t know about when it comes to the Great American Interchange is how marine animals were affected. It was exactly opposite for them. Instead of a new land to explore, which caused very different animals to encounter each other for the first time, the Isthmus of Panama cut populations of marine animals from each other. They’ve been evolving separately ever since. So I guess whether a land bridge is bad or good depends on your point of view.

You can find Strange Animals Podcast 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 for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 412: Whales and Dolphins

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Thanks to Elizabeth, Alexandra, Kimberly, Ezra, Eilee, Leon, and Simon for their suggestions this week!

Further reading:

New population of blue whales discovered in the western Indian Ocean

An Endangered Dolphin Finds an Unlikely Savior–Fisherfolk

The humpback whale:

The gigantic blue whale:

The tiny vaquita:

The Indus river dolphin:

The false killer whale:

Show transcript:

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

This week we’re going to have a big episode about various dolphins and whales! We’ve had lots of requests for these animals lately, so let’s talk about a bunch of them. Thanks to Elizabeth, Alexandra, Kimberly, Ezra, Eilee, Leon, and Simon for their suggestions.

We’ll start with a quick overview about dolphins, porpoises, and whales, which are called cetaceans. All cetaceans alive today are carnivorous, meaning they eat other animals instead of plants. This includes the big baleen whales that filter feed, even though the animals they eat are tiny. Cetaceans are mammals that are fully aquatic, meaning they spend their entire lives in the water, and they have adaptations to life in the water that are simply astounding.

All cetaceans alive today belong to either the baleen whale group, which filter feed, or the toothed whale group, which includes dolphins and porpoises. The two groups started evolving separately about 34 million years ago and are actually very different. Toothed whales are the ones that echolocate, while baleen whales are the ones that have extremely loud, often beautiful songs that they use to communicate with each other over long distances. It’s possible that baleen whales also use a limited type of echolocation to navigate, but we don’t know for sure. There’s still a lot we don’t know about cetaceans.

Now let’s talk about some specific whales. Ezra wanted to learn more about humpback and blue whales, so we’ll start with those. Both are baleen whales, specifically rorquals. Rorquals are long, slender whales with throat pleats that allow them to expand their mouths when they gulp water in. After the whale fills its mouth with water, it closes its jaws, pushing its enormous tongue up, and forces all that water out through the baleen. Any tiny animals like krill, copepods, small squid, small fish, and so on, get trapped in the baleen. It can then swallow all that food and open its mouth to do it again. The humpback mostly eats tiny crustaceans called krill, and little fish.

The humpback grows up to 56 feet long, or 17 meters, with females being a little larger than males on average. It’s mostly black in color, with mottled white or gray markings underneath and on its flippers. Its flippers are long and narrow, which allows it to make sharp turns.

The humpback is closely related to the blue whale, which is the largest animal ever known to have lived. It can grow up to 98 feet long, or 30 meters, and it’s probable that individuals can grow even longer. It can weigh around 200 tons, and by comparison a really big male African elephant can weigh as much as 7 tons. Estimates of the weight of various of the largest sauropod dinosaurs, the largest land animal ever known to have lived, is only about 80 tons. So the blue whale is extremely large.

The blue whale only eats krill and lots of it. To give you an example of how much water it can engulf in its enormous mouth in order to get enough krill to keep its massive body going, this is how the blue whale feeds. When it finds an area with a lot of krill floating around, it swims fast toward the krill and opens its giant mouth extremely wide. When its mouth is completely full, its weight—body and water together—has more than doubled. Its mouth can hold up to 220 tons of water. Since the whale is in the water, it doesn’t feel the weight of the water in its mouth.

Blue whales live throughout the world’s oceans, but a few years ago scientists analyzing recordings of whale song from the western Indian Ocean noticed a song they didn’t recognize. It was definitely a blue whale song, but one that had never been documented before. Not long after, one of the same scientists was helping analyze humpback whale recordings off the coast of Oman and recognized the same unusual blue whale song.

After the finding was announced, other scientists checked their recordings from the Indian Ocean and a few realized they had the mystery blue whale song too. The recordings come from a population of blue whales that hadn’t been documented before, and which may belong to a new subspecies of blue whale.

Elizabeth, Alexandra, and Leon all wanted to learn about dolphins. Kimberly also specifically wanted to learn about the Indus River dolphin and Leon about the vaquita porpoise. Dolphins and porpoises are considered toothed whales, but they’re also relatively small and can swim very fast. Orcas are actually dolphins even though they’re often called killer whales.

Even a small cetacean is really big, but the exception is the vaquita. It’s the smallest cetacean alive today, not even five feet long, or 1.5 meters. It lives only in the upper Gulf of California and is gray above and white underneath, with black patches on its face.

The vaquita spends very little time at the surface of the water, so it’s hard to spot and not a lot is known about it. It mostly lives in shallow water and it especially likes lagoons with murky water, since that’s where it can find lots of the small animals it eats, including small fish, squid, and crustaceans.

The vaquita is critically endangered, mostly because it often gets trapped in illegal gillnets and drowns.  There may be as few as ten individuals left alive. Attempts at keeping the vaquita in captivity have failed, but it’s strictly protected by both the United States and Mexico. Some scientists worry that even though vaquita females are still having healthy calves, there are so few of the animals left that they might not recover and are functionally extinct. But only time will tell, so the best thing everyone can do is what we’re already doing, keeping the vaquita and its habitat as safe as possible.

Another small cetacean is the Indus River dolphin, which grows up to 8 and a half feet long, or 2.6 meters. As you can probably guess from its name, it actually lives in fresh water instead of the ocean, specifically in rivers in Pakistan and India. It’s pinkish-brown in color and has a long rostrum, or beak-like nose, which turns up slightly at the end and is filled with sharp teeth that it uses to catch fish and other small animals. Because the rivers where it lives are murky, the dolphin doesn’t have very good eyesight. It probably can’t see anything except light and dark with its tiny eyes, but it can sense its surroundings just fine with echolocation.

Like most cetaceans, the Indus River dolphin is endangered, but it’s doing a lot better these days than it was just a few decades ago. In the 1970s only about 150 of the little dolphins were left alive, and by 2001 there were a little over 600. Today there are around 2,000. Habitat loss, pollution, and accidental drowning in fishing nets are still ongoing problems, but these days the fishing families that live along the river are helping it whenever they can. The fishers rescue dolphins who get stranded in shallow water and irrigation canals, and the government encourages this by paying the fishers a small amount for their help. Since this part of the country is very poor, a little bit of extra money can mean a big difference for the families, and of course their help means a lot to the dolphins too.

One interesting thing is that the Indus River dolphin often swims on its side. That is, it just tips over sideways and swims around as though that’s the most normal thing in the world. Scientists think this helps it navigate shallow water. And the Indus River dolphin isn’t very closely related to other dolphins and whales.

Quite a while ago now, Simon brought the false killer whale to my attention. In 1846 a British paleontologist published a book about British fossils, and one of the entries was a description of a dolphin. The description was based on a partially fossilized skull discovered three years before and dated to 126,000 years ago. It was referred to as the false killer whale because its skull resembled that of a modern orca. Scientists thought it was the ancestor of the orca and that it was extinct.

Or maybe not, because in 1861, a dead but very recently alive one washed up on the coast of Denmark.

The false killer whale is dark gray and grows up to 20 feet long, or 6 meters. It mostly eats squid and fish, including sharks. It’s not that closely related to the orca and actually looks more like a pilot whale. It will sometimes hang out with dolphins, including occasionally hybridizing with bottlenose dolphins, but then again sometimes it will eat dolphins. Watch out, dolphins.

Finally, Eilee wanted to learn about little-known whales, and that definitely means beaked whales. There are 24 known species of beaked whale, but there may still be species unknown to science. We know very little about most of the known species, because they live in remote parts of the ocean. They prefer deep water and are extremely deep divers, with the Cuvier’s beaked whale recorded as diving as deep as 1.8 miles, or almost 3 km, and staying underwater without a breath for 222 minutes. That’s approximately 220 minutes longer than a human can hold their breath.

Let’s finish with Sato’s beaked whale, which was only described in 2019. It’s black with a chunky body and small flippers and dorsal fin. It also has a short beak. It lives in the north Pacific Ocean and was thought to be a darker population of Baird’s beaked whale, which is gray, but genetic studies and a careful examination of dead beached individuals proved that it was a completely different species. It grows up to 23 feet long, or 7 meters, but since no female specimens have ever been found, we don’t know if the female is larger or smaller than the male.

We basically know nothing about this whale except that it exists, and the fact that it is alive and swimming around in the ocean right now, along with other whales, is an amazing, wonderful thing.

You can find Strange Animals Podcast 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 for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 406: Some Turtles and a Friend

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Thanks to Riley and Dean, Elizabeth, and Leo for their suggestions this week!

Further reading:

Groundbreaking study reveals extensive leatherback turtle activity along U.S. coastline

A bearded dragon:

The tiny bog turtle:

The massive leatherback sea turtle:

The beautiful hawksbill turtle [photo by U.S. Fish and Wildlife Service]:

Show transcript:

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

This week we’re going to learn about some reptiles suggested by four different listeners: Riley and Dean, Elizabeth, and Leo.

We’ll start with the brothers Riley and Dean. Dean wants to learn more about the bearded dragon, and that may have something to do with a certain pet bearded dragon named Kippley.

“Bearded dragon” is the name given to any of eight species of lizard in the genus Pogona, also referred to as beardies. They’re native to Australia and eat plants and small animals like worms and insects. They can grow about two feet long, or 60 cm, including the tail, but some species are half that length. Females are a little smaller than males on average.

The bearded dragon gets its name because its throat is covered with pointy scales that most of the time aren’t very noticeable, but if the lizard is upset or just wants to impress another bearded dragon, it will suck air into its lungs so that its skin tightens and the spiky scales under its throat and on the rest of its body stick out. They’re not very sharp but they look impressive. Since the bearded dragon can also change color to some degree the same way a chameleon can, when it inflates its throat to show off its beard, the beard will often darken in color to be more noticeable. Both males and females have this pointy “beard.”

Bearded dragons that are sold as pets these days are more varied and brighter in color than their wild counterparts, although wild beardies can be brown, reddish-brown, yellow, orange, and even white. Australia made it illegal to catch and sell bearded dragons as pets in the late 20th century, but there were already lots of them outside of Australia by then. Pet bearded dragons are mainly descended from lizards exported during the 1970s, which means they’re quite domesticated these days and make good pets.

Like some other reptiles and amphibians, the bearded dragon has a third eye in the middle of its forehead. If you have a pet beardie and are about to say, “no way, there is definitely not a third eye anywhere, I would have noticed,” the eye doesn’t look like an eye. It’s tiny and is basically just a photoreceptor that can sense light and dark. Technically it’s called a parietal eye and researchers think it helps with thermoregulation.

Next, Riley wants to learn about turtles, AKA turbles, and especially wants everyone to know the difference between a tortoise and a turtle. It turns out that while many turtles are just fine living on land, they’re often more adapted to life in the water. Turtles have a more streamlined shell and often flipper-like legs or webbed toes. Tortoises only live on land and as a result they have shells that are more dome-shaped, and they have large, strong legs that resemble those of a tiny elephant.

You can’t always go by an animal’s common name to determine if it’s a tortoise or a turtle, but it’s also not always clear whether an animal is a tortoise or a turtle at first glance. Take the eastern box turtle, for instance, which is common in the eastern United States. It has a domed carapace, or shell, but it’s still a turtle, not a tortoise. And, I’m happy to say, it can swim quite well. This is a relief to find out because when I was about six years old, my mom visited someone who had kids a little older than me. I didn’t know them but they were nice and showed me the swampy area near their house. At one point one of the older boys found a box turtle, took it over to a little bridge over a pond, and dropped it in the water. I screamed, and he was absolutely shocked. He said he thought box turtles belonged in the water and he was helping it, but I thought they couldn’t swim and he’d just killed the poor turtle. I have continued to think he’d killed the poor turtle until just now, when I learned they can swim, and I can’t even tell you how relieved I am. Anyway, eastern box turtles have a domed shell, yes, and stumpy club-like front legs, but their hind legs are less like elephant legs than regular turtle legs. Since box turtles can live to be 100 years old, it’s possible that that one is alive and well even now.

Riley also wants everyone to know not to take a turtle from the woods, which is a very good rule to live by. In fact, it’s important not to take any wild animals from the woods no matter how cute they are. To continue our example, eastern box turtles have small territories that they defend from other box turtles. If you take the turtle out of its territory even for just a few days, when you return it to the woods, another turtle may have already taken over and will chase it away. Turtles don’t travel very fast and are vulnerable to being hit by cars and eaten by lots of different predators, so without a safe territory where it can hide and find food, it can die very quickly.

One of the turtles Leo suggested we learn about was the bog turtle. It’s the smallest turtle in North America, with a carapace barely four inches long, or 10 cm. It lives in a few parts of the eastern United States, and likes marshy areas with slightly acidic water. It spends a lot of time in the water, but also plenty of time on land. It eats worms, slugs, snails, water plants, berries, insects, and even small frogs when it can catch them.

The bog turtle is so small that pretty much anything big enough to swallow it will eat it. Its main defense is to bury itself in soft mud and hide. It’s almost completely black or dark gray in color, but it does have a bright orange spot on each side of its neck.

The bog turtle is critically endangered due to habitat loss, pollution, and poaching for the illegal pet trade. Conservationists are working to improve its habitat, and in the meantime some zoos and aquariums are helping with a captive breeding program. Since a bog turtle isn’t old enough to lay eggs until it’s at least 8 years old, the species as a whole reproduces slowly.

Leo also suggested hawksbill and leatherback turtles, and Elizabeth wants to learn about sea turtles in general. We talked about sea turtles way back in episode 75, so it’s definitely time to revisit the topic.

Seven species of sea turtle are alive today, and you can tell they’re turtles and not tortoises because they have streamlined shells and flippers instead of feet. They migrate long distances to lay eggs, thousands of miles for some species and populations, and usually return to the same beach where they were hatched. Female sea turtles come ashore to lay their eggs in sand, but the males of most species never come ashore. The exception is the green sea turtle, which sometimes comes ashore just to bask in the sun. Once the babies hatch, they head to the sea and take off, swimming far past the continental shelf where there are fewer predators. They live around rafts of floating seaweed call sargassum, which protects them and attracts the tiny prey they eat.

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

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

The hawksbill, or hawkbill sea turtle grows to a much more reasonable size, around three feet long, or 90 cm, and mostly lives around tropical reefs. It has a more pointed, hooked beak than other sea turtles, sort of like a hawk, which gives it its name. You might think it eats fish with a beak like that, but it mostly eats jellyfish and sea sponges. It especially likes the sea sponges, some of which are lethally toxic to most other animals. It also doesn’t have a problem eating even extremely stingy jellies and jelly-like animals like the Portuguese man-o-war. The hawkbill’s head is armored so the stings don’t bother it, although it does close its eyes while it chomps down on jellies. Its meat can be toxic due to the toxins it ingests. People used to kill hawksbill sea turtles for their multicolored shells, but these days it’s a protected species like all sea turtles.

The hawksbill is also biofluorescent! Researchers only found this out by accident in 2015, when a team studying biofluorescent animals in the Solomon Islands saw and filmed a hawksbill glowing like a UFO with neon green and red light. So you never know what other secrets sea turtles might be hiding.

You can find Strange Animals Podcast 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 for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 404: The Kraken and Chessie

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Thanks to Ezra and Leo for suggesting these two sea monsters this week! Happy Halloween!

Further reading:

Legend of Chessie alive, well in Maryland

Here be sea monsters: We have met Chessie and…is it us?

Not actually a kraken, probably:

Not actually Chessie but an atmospheric photo of a toy brontosaurus:

Show transcript:

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

Just a few days remain in October, so this is our Halloween episode and the end of monster month for another year! We had so many great suggestions for Halloween episodes that I couldn’t get to them all, but I might just sprinkle some in throughout the other months too. We have two great monsters to talk about this week, suggested by Ezra and Leo, the kraken and Chessie the sea serpent.

First, as always on our Halloween episode, we have a few housekeeping details. If anyone wants a sticker, feel free to email me and I’ll send you one, or more than one if you like. That offer is good all the time, not just now. I don’t have any new stickers printed but I do have lots of the little ones with the logo and the little ones with the capybara.

I also don’t have any new books out this year, but you can still buy the Beyond Bigfoot & Nessie book if you like. I am actually working on another book about mystery animals, tentatively titled Small Mysteries since it’s going to be all about mysteries surrounding small animals like frogs and invertebrates that often get overlooked. I’m hoping to have it ready to publish in early 2026 or so. I don’t know that I’ll do another Kickstarter for it since that was a lot of work, and I just finished a Kickstarter for more enamel pins and just can’t even think about the stress of doing another crowdfunding campaign anytime soon. Also, I hate to keep asking listeners for money.

Anyway, one of the things I don’t like about Beyond Bigfoot & Nessie is that I didn’t cite my sources properly, so for the Small Mysteries book I’m being very careful to have footnotes on pretty much every page so that anyone who wants to double-check my information can do so easily.

But all that is in the future. Let’s celebrate Halloween now with a couple of sea monsters!

We’ll start with Ezra’s suggestion, the kraken. It’s a creature of folklore that has gotten confused with lots of other folklore monsters. We don’t know how old the original legend is, but the first mention of it in writing dates to 1700, when an Italian writer published a book about his travels to Scandinavia. One of the things he mentions is a giant fish with lots of horns and arms, which he called the “sciu-crak.” This seems to come from the Norwegian word meaning sea krake.

“Krake” is related to the English word crooked, and it can refer to an old dead tree with crooked branches, or tree roots, or something with a hook on the end like a boat hook, or an anchor or drag, or various similar things related to hooks or multiple prongs. That has led to people naturally assuming that the kraken had many arms and was probably a giant squid, and that may be the case. But there’s another possibility, because in many old uses of the word krake, it means something weak or misshapen, like a rotten old dead tree. In the olden days in Norway, people thought that if you spoke about an animal by name, the spirit that protected that animal would hear you. Some historians think that whale-hunters referred to whales as krake so the whale’s protective spirit wouldn’t guess that they were planning a whale-hunt. Who would refer to a huge, strong animal like a whale as weak and crooked, after all?

Whatever its origins, the kraken’s modern form is mainly due to a Danish bishop called Erik Pontoppidan. He wrote about the kraken in 1753, and embellished the story by saying the kraken could reach out of the ocean with its long arms to grab sailors or just pull an entire ship down into the water and sink it. He also said the kraken was so big that when it rested at the water’s surface, sailors would mistake it for an island. This is a common story in many cultures, always referring to whales. Pontoppidan suggested the kraken might be a giant octopus, but also thought it might be a giant starfish or even a giant crab. He seemed to think the word kraken should be krabben, and I swear I didn’t make that up.

Either way, the kraken is a monster of folklore, not a real animal. That’s a relief! Now you don’t have anything to worry about in the ocean at all, right?

Next, let’s learn about another water monster, Chessie, suggested by Leo. Leo also suggested we talk about Chesapeake Bay in general.

Chesapeake Bay is located on the east coast of North America, specifically where the states of Virginia, Maryland, and Delaware meet. On the map it looks sort of like a huge crack in the land, but while rivers and streams empty into it like they would a gigantic lake, it’s connected to the Atlantic Ocean. It’s about 200 miles long, or 320 km, and up to 30 miles wide, or 48 km.

It formed about 35 million years ago when a small meteor struck the area. During the Pleistocene, AKA the ice ages, the Susquehanna River flowed through the crater and into the sea. Around 10,000 years ago, ocean levels rose due to melting glaciers, and flooded the river valley that had started out as an impact crater. Now it’s a bay.

Chesapeake Bay isn’t technically a lake, but it’s also not really part of the ocean. Part of the bay is freshwater from the rivers that flow into it, while at the end that connects to the Atlantic Ocean, it’s salty. In between it’s brackish water that’s kind of salty but not nearly as salty as the ocean. It’s home to hundreds of animals, with many more visiting the bay during migration. Sometimes whales are even spotted in the bay.

We could literally talk about the animals and the history of Chesapeake Bay all day and not run out of topics, so I have plans to revisit some of the animals in future episodes. Today we mainly want to focus on the sea monster known as Chessie.

As you may have already guessed, the name Chessie isn’t just short for Chesapeake, it also echoes the name Nessie, the Loch Ness Monster. The first Nessie sighting was in 1933, leading to a lake monster craze in Scotland and many other parts of the world. Suddenly people were seeing monsters everywhere, such as Champ from Lake Champlain, which we talked about in episode 29 along with Nessie.

No one’s sure when the first Chessie sighting happened. Some people say it was as early as 1936, while others claim it wasn’t until 1980. In 1943 two fishermen reported seeing a strange creature in the water about 75 yards from their boat, or 68 meters. At first they thought there was something black floating in the water, with the visible part of it about 12 feet long, or 3 ½ meters. Then they realized it was alive. Its head was shaped like a horse’s but was only about the size of an American football. It’s not clear if it raised its head completely out of the water like a sea serpent in a cartoon, but the men did say that it turned its head almost all the way around several times.

There are also reports from 1977, 1978, 1980, 1982, 1997, and 2014. In 1978 a retired CIA officer saw what looked like a 15-foot, or 4 ½ meter, snake swimming in the water. In 1982 a man named Bob Frew took some grainy videocamera footage of something that he described as “a telephone pole that swims.” The video shows a brown object swimming like a marine snake, with a side to side motion.

In the 1980s people in the state of Maryland tried to get Chessie listed as a protected species. It didn’t work, but it did bring attention to the state of the Chesapeake Bay. The bay was increasingly polluted by industrial and agricultural waste that was allowed to enter the bay untreated, leading to algal blooms that deoxygenated the water and killed everything around them. The once-famous oyster reefs in the bay started to be overharvested too, and since oysters are natural water filters, their absence has caused an extra decrease in water quality. With Chessie acting as a mascot for water quality and ecology, people paid more attention to what was happening to the bay.

Chessie the monster doesn’t have a lot of sightings, and most likely they’re all misidentifications of ordinary animals or items, like whales or floating logs. There are some amazing creatures that live in or visit the bay, including a fish called the sturgeon that can grow up to 15 feet long, or 4.6 meters, bull sharks that can grow up to 13 feet long, or 4 meters, bottlenose dolphins, sea turtles, even manta rays. Most people agree that Chessie probably isn’t an actual sea serpent.

But there is another Chessie that’s definitely real, although you can’t actually call him a monster. A Florida manatee was spotted in the summer of 1994 swimming around in the bay and exploring some of the river mouths. Since Chesapeake Bay is nice and warm in summer, the manatee was fine at first. But by October he was still there, and the water was getting too cold for a manatee to tolerate.

Maryland’s Department of Natural Resources worked with the Coast Guard and a lot of volunteers to find the manatee, capture him safely, and get him back to Florida. He was given a clean bill of health by veterinarians and was tagged and released.

The following summer, he swam back to Chesapeake Bay. But who can blame him? It’s a beautiful place!

You can find Strange Animals Podcast 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 for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 402: The Hoop Snake and Friends

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Thanks to Nora and Richard from NC this week as we learn about some scary-sounding reptiles, including the hoop snake!

Further reading:

The Story of How the Giant “Terror Skink” Was Presumed Extinct, Then Rediscovered

San Diego’s Rattlesnakes and What To Do When They’re on Your Property

Snake that cartwheels away from predators described for the first time

Giant new snake species identified in the Amazon

The terror skink, AKA Bocourt’s terrific skink [photo by DECOURT Théo – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=116258516]:

The hoop snake according to folklore:

The sidewinder rattlesnake [photo taken from this article]:

The dwarf reed snake [photo by Evan Quah, from page linked above]:

The green anaconda [photo by MKAMPIS – Own work, CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=62039578]:

Show transcript:

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

As monster month continues, we’re going to look at some weird and kind of scary, or at least scary-sounding, snakes and lizards. Thanks to Nora and Richard from NC for their suggestions this week!

We’ll start with the terror skink, whose name should inspire terror, but it’s also called Bocourt’s terrific skink, which is a name that should inspire joy. Which is it, terror or joy? I suppose it depends on your mood and how you feel about lizards in general. All skinks are lizards but not all lizards are skinks, by the way.

The terror or possibly terrific skink lives on two tiny islets, which are miniature islands. These islets are themselves off the coast of an island called the Isle of Pines, but in French, which I cannot pronounce. The Isle of Pines is only 8 miles wide and 9 miles long, or 13 by 15 km, and is itself off the coast of the bigger island of New Caledonia. All these islands lie east of Australia. Technically the islets where the skink lives are off the coast of another islet that is itself off the coast of the Isle of Pines, which is off the coast of New Caledonia, but where exactly it lives is kept a secret by the scientists studying it.

The skink was described in 1876 but only known from a single specimen captured on New Caledonia around 1870, and after that it wasn’t seen again and was presumed extinct. Colonists and explorers brought rats and other invasive animals to the New Caledonian islands, which together with habitat loss have caused many other native species to go extinct.

But in December 2003, a scientific expedition studying sea snakes around the New Caledonian islands caught a big lizard no one recognized. Once the expedition members realized it was a terror skink, alive and well, they took lots of pictures and videos of it and then released it back into the wild. Since then, more specimens have been discovered during four different expeditions, but only on the islets, not on any of the bigger islands. It’s so critically endangered that its location has to be kept secret, because if someone captures some of the lizards to sell on the illegal pet market, the species could easily be driven to extinction.

The terror skink is gray-brown with darker stripes, a long tail, and a slightly downturned mouth that makes it look grumpy. It grows about 20 inches long, or 50 cm, including its tail. This is really big for a skink, so technically it’s a giant skink.

It gets the name terror skink from its size and from its teeth, which are large and curved like fangs. It mainly eats one particular species of land crab, which is why its jaws are so strong and its teeth are so sharp, so it can bite through the crab’s exoskeleton.

Another lizard with a spooky name that has been presumed extinct is the gray ghost lizard, suggested by Richard from NC. It’s more properly called the giant Tongan ground skink, and it’s native to some more South Pacific islands—specifically, the Tongan Islands. These islands are even farther east from Australia than the New Caledonian islands, and are actually closer to New Zealand than to Australia, although they’re not really very close to either.

The giant Tongan ground skink was described in 1839 from two specimens collected in the late 1820s on Tongatapu Island. They’re the only two specimens known and the lizard is considered extinct, especially considering that these days, the island is almost completed deforested and rats, dogs, and cats have been introduced to it, which has driven many species to extinction.

But after the terror skink was rediscovered, scientists started to wonder if the gray ghost might still be around. It was called the gray ghost because it was so hard to see, since it was dark gray in color. The native Tongan people considered it a good omen if someone saw one, since it was so rare.

A paper published in early 2024 suggests that the gray ghost might be living on some smaller islands where forests still remain, and also suggested that it might be nocturnal and a burrowing skink. That would explain why it was so rarely seen by the people who lived on its island when it was still alive.

We know basically nothing about the gray ghost. Hopefully an expedition to the smaller Tongan islands will rediscover it so we can learn more about it and protect it.

Richard from NC also suggested we talk about the hoop snake, an animal of folklore. I remember reading about it as a kid in a book about American folklore animals, most of which were clearly jokey and not meant to seem real. The hoop snake sounded more realistic.

The hoop snake was supposed to be a long, slender snake that slithered around normally most of the time, but when it needed to move faster, it would grab the end of its tail in its mouth and roll like a wheel, or a hoop. Some versions of the story had the snake rolling along with the tip of its tail pointed forward, and since the tail was supposed to be sharp and venomous, it would roll after you so fast that when its tail stabbed you, you’d drop dead. The only way to escape would be to jump behind a tree. The tail would stab the tree instead and you could run away while the hoop snake was trying to unstick its tail. The venom in its tail was supposed to be so deadly that the tree would turn black and die. Other versions of the story said you had to jump through the snake’s hoop to confuse it, which would allow you to get away safely.

All this is weird, to say the least, but some snakes do have ways of traveling that are unusual. The sidewinder, for instance, is a real species of rattlesnake from the southwestern United States and northwestern Mexico. It grows around 2 ½ feet long, or 80 cm, and has pointy scales, called keeled scales, including a pair above its eyes that make it look like it has little horns. Since it’s a type of rattlesnake, it has a rattle that it can shake to make a loud warning noise. It’s mostly brown in color, or sometimes pinkish, yellowish, or even whitish, with darker stripes or blotches down its back. Its coloration helps camouflage it against the ground, and it will actually change color slightly depending on the temperature. This is something other rattlesnakes can do too.

The sidewinder lives in desert conditions where it has to travel through loose sand, and the sand is also extremely hot. While the snake can travel normally when it wants to, it sidewinds to move quickly over loose sand or very hot sand that might burn it. It lifts most of its body up so that it’s only touching the ground in two places, then undulates its body so that the sections touching the ground constantly move. That way no part of its body has to stay in contact with hot sand for more than a split second. It travels in a path that runs diagonal to the direction its body is pointing. That sounds complicated, but it’s easy for the snake. It’s not even the only snake that can travel by sidewinding. Other desert-living snakes travel across hot sand by sidewinding, including several species from Africa, but just about any snake can do it if they need to. It allows a snake to travel over surfaces that are too slippery for its belly scales to get a grip.

The story of the hoop snake might be based on garbled reports of sidewinders, but it might just be a completely invented animal. The hoop snake story is found in other parts of the world too, especially Australia, although it dates back to at least the late 18th century in the United States.

No snake in the world has the anatomy to allow it to roll like a hoop without hurting itself. But there is one other snake that does something very similar, called cartwheeling. It’s the dwarf reed snake that lives in Malaysia and other parts of southeast Asia. Reed snakes aren’t very well known to science, so this cartwheeling activity wasn’t documented scientifically until recently, with the study published in 2023. Reed snakes are nocturnal and spend most of the daytime hiding under rocks or logs, or buried in dead leaves or sand, so they’re not seen very often by people. The dwarf reed snake is slender and only grows about 10 inches long, or 25 cm.

Some small snakes can jump short distances by pushing their tails against the ground. The dwarf reed snake does something similar, but more complicated. It pushes off with its tail, with its body curved in a sort of S shape. It lands on its head and rolls over completely, head to tail, and then pushes off the ground again with its tail. It can move extremely fast in this way to get away from predators, but it takes a whole lot of energy. But when it’s moving downhill, with gravity on its side, it can continue to cartwheel longer.

Cartwheeling isn’t something the snake does often, and it’s rare that a human would ever observe it. But just like sidewinding, some scientists think cartwheeling might be a motion that more snakes can do if they really need to. Maybe that’s where the hoop snake legend started.

Let’s finish with a suggestion from Nora, who wanted to learn more about the green anaconda. That’s a scary snake for sure, because it happens to be the biggest snake alive today, and almost the longest, as far as we know.

The green anaconda lives throughout much of South America, although not in Patagonia because like most reptiles, it needs warm weather to function. It’s a beautiful olive green with black blotches, and it’s a big, bulky snake. It spends a lot of time in the water, which helps it stay cool in hot weather and helps support its weight comfortably, and its eyes are near the top of its head so it can watch for prey while it’s mostly submerged.

The anaconda is a member of the boa family and is a constrictor. It’s not venomous, but you really don’t want a hug from a hungry anaconda. Its body is bulky because it’s incredibly strong, and once it starts to contract its muscles, whatever it’s constricting has only minutes left to live. It can kill animals as large as caimans, which are a type of crocodile, tapirs, capybaras, deer, and even jaguars. For the most part, though, an anaconda doesn’t want to bother with prey that could potentially hurt it, so it will stick with smaller animals that are still big enough to make it worth the effort. And yes, it is possible that an anaconda in the wild could kill and eat a human, but there’s no reliable evidence that it’s ever happened.

It’s hard to know exactly how long and how heavy an anaconda can get. There are lots of stories of 30-foot, or 9-meter snakes, but that seems to be a wild exaggeration. Snakes are stretchy, and a healthy live snake doesn’t really want to stretch out straight to be measured. A dead snake is even stretchier than a live snake. A shed snakeskin is the stretchiest of all, and usually has stretched out quite a bit when the snake was shedding. A good estimate is that a big female anaconda can grow about 20 feet long, or 6 meters, and can weigh around 250 lbs, or 114 kg. Males are smaller on average, and a wild snake will weigh less than one kept in captivity.

There are definitely larger individual anacondas, especially considering that reptiles continue to grow throughout their lives, but they’re probably not that much longer. This is only a little shorter than the reticulated python, which can definitely grow up to 23 feet long, or 7 meters.

One important detail about the size of the green anaconda is that the biggest snakes live in the Amazon rainforest–but the Amazon rainforest is really hard for humans to navigate safely and most anacondas killed or kept in captivity lived in other parts of South America. So there might easily be anacondas in the rainforest that are much bigger than the ones scientists have been able to measure so far.

In February of 2024, a journal article was published about a 2022 National Geographic nature documentary and scientific expedition to the Amazon basin to find a rumored population of extra-large anacondas. The expedition was led by hunters from the Waorani people, who consider the snakes sacred, and the hunters and their chief were credited as co-authors of the paper, as they should be since they provided so much information.

The scientists were able to examine several fully grown anacondas and take tiny tissue and blood samples to test later. They were astounded at the size of the snakes they found, including one that measured 20 and a half feet long, or 6.3 meters. The hunters reported seeing snakes that they estimated as over 24 feet long, or 7.5 meters, that might have weighed as much as 500 pounds, or 226 kg.

Beyond mere size, though, is something very interesting, which the scientists learned when they got home and ran genetic tests. The anacondas are actually quite different genetically from other anacondas known to science, that live farther south. They described the snake as a new species, which they refer to as the northern green anaconda, but it has actually resulted in a lot of controversy. Some scientists agree that the northern green anaconda is a separate species, others think it’s only a subspecies of the green anaconda, while others think the genetic differences are minor and separating the northern green anaconda from other anacondas isn’t justified by the evidence.

Obviously scientists need to follow up and learn more about the anacondas, but one thing is clear. There are some really, really big snakes out there in the Amazon.

You can find Strange Animals Podcast 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 for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 399: Bears

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Thanks to Anbo, Murilo, Clay, and Ezra for their suggestions this week! Let’s learn about some bears!

Further reading:

Snack attack: Bears munch on ants and help plants grow

Extinct vegetarian cave bear diet mystery unravelled

Ancient brown bear genomes sheds light on Ice Age losses and survival

The sloth bear has shaggy ears and floppy lips [photo from this site]:

An absolute unit of a Kodiak bear in captivity [photo by S. Taheri – zoo, own work, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=1118252]:

A polar bear:

Show transcript:

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

This week we’re revisiting a popular topic, bears! We’ll talk about some bears we’ve never covered before, with suggestions from Anbo, Clay, Ezra, and Murilo. We’ll even discuss a small bear mystery which has mostly been solved by science.

To start us off, Anbo wanted to learn about bears in general. We’ve had bear episodes before, but our last episode all about bears was way back in 2017, in episode 42. Some of our listeners weren’t even born back then, which makes me feel super old.

Bears live throughout much of the world today, but they evolved in North America around 38 million years ago. These ancestral bears were small, about the size of a raccoon, but they were successful. They spread into Asia via the land bridge Beringia, where they were even more successful than in North America, so successful that by around 30 million years ago, descendants of those earliest bear ancestors migrated from Asia back into North America. But it wasn’t until the Pleistocene around 2 ½ million years ago that bears really came into their own.

That’s because bears are megafauna, and megafauna evolved mainly as an adaptation to increasingly cold climates. As the ice ages advanced, a lot of animals grew larger so they could stay warm more easily. Predators also had to grow larger as their prey became larger, since if you want to hunt an animal the size of a bison or woolly rhinoceros, you’d better be pretty big and strong yourself.

Bears mostly weren’t hunting animals that big, though. Modern studies suggest that overall, bears are omnivores, not fully carnivorous. Bears eat a lot of plant material even if you don’t count the panda, which isn’t very closely related to other bears. Even when a bear does eat other animals, they’re not usually very big ones.

Let’s take Murilo’s suggestion as an example, the sloth bear. The sloth bear lives in India and is increasingly vulnerable due to habitat loss and poaching. It’s probably most closely related to the sun bear that we talked about in episode 234, which also lives in parts of South Asia. Both the sun bear and the sloth bear have long black hair and a white or yellowish V-shaped marking on the chest. The sloth bear’s hair is especially long on its neck and shoulders, like a mane, and its ears even have long hair.

The sloth bear stands around 3 feet high at the shoulder at most, or 91 cm, and a big male can be over 6 feet tall, or almost 2 meters, when he stands on his hind legs. This isn’t gigantic for bears in general, but it’s not small either. Scientists think the V-shaped marking on its chest warns tigers to leave the sloth bear alone, and tigers mostly do. If tigers think twice about attacking an animal, you know that animal has to be pretty tough.

The sloth bear has massive claws on big paws. The claws can measure 4 inches long, or 10 cm, although they’re not very sharp. The bear has an especially long muzzle but its teeth aren’t very large. Like most bears, it’s good at climbing trees and can run quite fast, and it swims well too. It even has webbed toes.

With all this in mind, what do you think the sloth bear eats? I’ll give you some more hints. It has loose, kind of flappy lips, especially the lower lip. It doesn’t have any teeth in the front of its upper jaw. It mainly uses its huge claws to dig.

If you guessed that the sloth bear eats ants, termites, and other insects, you are right! It digs into termite and ant nests and uses its long, flexible lips to slurp up as many insects as it can, giving them a quick crunch with its back teeth before swallowing them down.

Insects are actually quite nutritious, and the sloth bear isn’t the only bear that eats them. All bears snack on ants and other insects sometimes. You may have heard that bears love honey and will tear open beehives to get it, and while that’s true, the bear is mainly after the larval bees because they’re so nutritious. The honey is just, you know, dessert.

Next, Clay wanted to learn about the Kodiak bear, which may be the largest bear in the world. It’s a subspecies of brown bear and is sometimes called the Alaskan brown bear since it lives on some Alaskan islands called the Kodiak Archipelago. It’s light brown or rusty-red in color.

The Kodiak bear has been restricted to these islands for at least 10,000 years, since the end of the Pleistocene when the sea levels rose as glaciers melted. It demonstrates island gigantism, which is actually quite unusual. Because islands have limited resources, but are relatively protected from large numbers of predators, small animals are the ones that generally adapt to island life by growing larger. Animals that start off large generally adapt by growing smaller, called island dwarfism. That’s why some islands have been home to dwarf elephants but giant rodents.

In the case of the Kodiak bear, it has a source of protein that helps it grow so incredibly large, salmon. Five species of salmon spawn in the freshwater on the islands, and the bears are able to put on lots of weight to survive the harsh winter by eating as much salmon as they can catch. They also have lots of nutritious plants to eat. They actually prefer some plants to eating salmon, which makes sense when you think about it. A wild animal needs to conserve energy, and it can take a lot of energy to catch fish. It’s a lot easier to eat berries, which can’t swim away.

So how big can a Kodiak bear get? A big male can stand up to 10 feet tall on his hind legs, or 3 meters, and be 5 feet tall, or 1.5 meters, when standing on all fours. Bears kept in captivity can grow even larger. That’s much bigger than a grizzly and about the same size as the closely related polar bear, which brings us to Ezra’s suggestion.

Ezra wanted to learn about the polar bear, which lives in the Arctic and areas near the Arctic. It doesn’t live near the Antarctic, or south pole, which means polar bears don’t eat penguins, because penguins live around the Antarctic. The polar bear does eat a whole lot of other animals, though, and is the most carnivorous of all bears. It especially likes eating seals, and will also catch and kill walruses, caribou, and beluga whales. That’s right, the polar bear can actually kill an entire whale. The beluga is fairly small for a whale and relies on breathing holes in the ice, and sometimes when it comes up to breathe, there’s a polar bear waiting for it. Most of the time, though, the polar bear eats much smaller animals.

The polar bear spends a lot of its time on sea ice, and a lot of the time in the sea. It swims incredibly well and spends so much time in the water that some people consider it a marine animal. It’s certainly semi-aquatic. Its kidneys are adapted to filter excess salt out of its blood from seawater, and its small eyes are closer to the top of its head than in other bears. This helps it see above water while swimming.

The polar bear is closely related to the brown bear and will sometimes interbreed with the brown bear where their ranges overlap. The resulting hybrid bear is usually light brown in color. The polar bear is famously white, although its fur becomes yellowish as the year goes on. It sheds its winter coat in the spring and the new hair that grows in is white.

Actually, the polar bear’s fur is transparent, but it looks white because of the way it scatters light. The guard hairs are long and coarse, protecting a shorter, softer undercoat that helps keep the bear warm even on bitterly cold nights. Unlike other bears, the polar bear doesn’t hibernate, except for pregnant females.

There used to be a bear of similar size that lived in Europe and Asia during the Pleistocene and only went extinct about 24,000 years ago. The cave bear gets its name because so many of its remains have been found in caves. It may have hibernated in caves like some bears do today, or it might have used caves as shelters year-round.

Scientists think the cave bear was most closely related to brown bears and polar bears. The males were much larger than females, and a big male was as big as a Kodiak or polar bear. But this giant bear probably wasn’t too much of a problem for our ancient ancestors and Neandertal relations, because it was almost entirely vegetarian.

Scientists have studied the wear pattern on cave bear teeth and determined that it was eating a whole lot of fruit, especially berries. It probably did eat at least some meat, but it’s likely that most of it came from scavenged carcasses. The cave bear didn’t even have all the teeth that other bears have.

All this talk about huge bears brings us to a mystery. It may even be a mystery you were wondering about yourself. How did bears survive the end of the Pleistocene when so many other megafauna went extinct, from the mammoth and giant ground sloth to the dire wolf and sabertooth cat?

A team of scientists from Denmark and Japan decided to examine the genetics of ancient brown bears, to learn how individuals were related and therefore how bears migrated across the world over time. They extracted genetic material from the remains of bears that lived as much as 60,000 years ago and as recently as 3,800 years ago and compared them to each other and to bears alive today.

Scientists already knew that brown bears used to live in more parts of the world than they do today. The prevailing view was that as the climate warmed after the ice ages, the bears retreated into colder parts of the world where they were more comfortable. But the team learned something surprising from the study, which was published in January of 2024.

Brown bears that lived before the end of the Pleistocene, approximately 11,000 years ago, had much broader genetic diversity than the bears that lived more recently. That means that bears that lived as far south as Japan and Ireland during the Pleistocene didn’t move to colder parts of the world, they died out. Each population that went regionally extinct made the brown bear gene pool that much smaller.

Most likely it was a combination of luck and adaptability that allowed bears to survive the end-Pleistocene extinctions. Just think how sad it would be if I ended this episode by saying that bears went extinct 11,000 years ago. Instead, we can still go to the zoo and see all kinds of bears whenever we want to.

You can find Strange Animals Podcast 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 for as little as one dollar a month and get monthly bonus episodes.

Thanks for listening!

Episode 391: Welcome to Snake Island

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Follow the enamel pin Kickstarter here!

Let’s learn about some snakes this week! Thanks to Eilee, BlueTheChickenWing, and Richard from NC for their suggestions.

Further Reading:

Snake Island’s Venomous Vipers Find a New Home in Sao Paulo

‘Rarest Snake’ in the U.S. Hatches at Tennessee Zoo

The golden lancehead [picture from first article linked above]:

The Martinique lancehead/fer-de-lance:

The Louisiana pine snake, and a pine cone:

Show Transcript:

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

After today, the next four weeks will be all about invertebrates, or animals without a backbone, because it’s almost Invertebrate August! But this week let’s learn about some animals that are basically nothing but backbones, snakes! Thanks to Eilee, BlueTheChickenWing, and Richard from NC for their suggestions!

Also, if you like enamel pins even slightly as much as I do, I’m starting a Kickstarter in a few weeks to make some more. These will be bigger than the ones I made a few years ago and will include an aye-aye. Where else are you going to get an aye-aye enamel pin? There’s a link in the show notes if you want to sign up for an email reminder when the campaign goes live in mid-August. https://www.kickstarter.com/projects/kateshaw/familiar-friends-enamel-pins

Anyway, let’s start with Snake Island, suggested by Eilee. Snake Island is off the coast of Brazil in South America, and it’s quite small, only about 106 acres total, or 43 hectares. It’s hilly and a little over half of it is covered with a temperate rainforest, while the rest is grassy or just bare rocks. No one lives there these days and it’s a protected area that only scientists are allowed to visit, with the exception of members of the Brazilian navy who occasionally stop by to maintain the lighthouse that keeps ships from smashing into the rocky coast. Lots of birds live on the island or visit there, but other than that it’s mostly just snakes.

Specifically, the critically endangered golden lancehead pit viper lives on Snake Island and nowhere else in the world. It can grow nearly four feet long, or 118 cm, and is pale gold or golden-brown in color with darker splotches. It’s also incredibly venomous—but no one has ever been bitten by one as far as we know. If somehow you were bitten by one, it probably wouldn’t be a pleasant situation but you also probably wouldn’t die. That’s mainly because the golden lancehead’s venom is adapted to kill birds and reptiles, not mammals. And that’s because there are no mammals living on Snake Island.

The golden lancehead spends most of its time in trees or bushes, hunting for birds. It mainly eats two particular species of small bird that live on the island, although it will also eat other birds, lizards, and invertebrates like insects. Some reports say it will even eat smaller golden lanceheads. There’s another snake that lives on the island, Sauvage’s snail-eater, and the golden lancehead might occasionally snack on one of those. The snail-eater is also present on mainland Brazil and isn’t venomous. You can probably guess that it mainly eats snails. It’s small and thin, lives in trees, and is brownish-yellow with darker stripes and splotches.

The issue with Snake Island and its snakes is that there isn’t that much land available for the snakes to live on, and the forest has been damaged by human activity. Big chunks of forest were cleared by fire when people decided to try growing bananas on the island, which didn’t work very well. No one lives there now, but poachers do occasionally visit the island to catch snakes for the illegal wildlife trade. The golden lancehead is starting to show signs of inbreeding and disease as a result. As if that wasn’t bad enough, because the island is so close to the coast of Brazil, and mainland Brazil has its own problems with deforestation, fewer birds are migrating through the area every year. That means fewer birds stop at Snake Island and the snakes have less to eat.

Some reports claim that the island is so overrun by snakes that you’d encounter one with every step if you visited, but that’s not actually true. The snakes don’t live everywhere, and they spend almost all their time in trees. Recent studies estimate that around 2,000 to 4,000 snakes live on the island, which sounds like a lot until you remember that these are the only golden lanceheads in the whole world! Fortunately, rumors that anyone who sets foot on the island is at risk of being bitten and dying horribly from the golden lancehead’s venom keep a lot of people away. A captive breeding program in São Paulo, Brazil is also working to help the snakes.

The golden lancehead is a type of pit viper, closely related to other pit vipers found in Brazil. Its ancestors were trapped on the island when ocean levels rose at the end of the Pleistocene, around 11,000 years ago, and it’s been evolving separately ever since. Species in the genus Bothrops are also called fer-de-lance snakes, and that brings us to our next suggestion from BlueTheChickenWing.

BlueThe ChickenWing left us a nice review a while back and made two suggestions, one of which is the fer-de-lance. Fer-de-lance is a French term meaning spearhead, or lancehead, as in golden lancehead. The golden lancehead belongs to the genus Bothrops, pit vipers that are found throughout much of Central and South America as well as some Caribbean islands. We’re only going to talk about one other species of fer-de-lance this week, though, Bothrops lanceolatus, also called the Martinique lancehead. It too lives on an island, in this case the Caribbean island of Martinique.

The Martinique lancehead can grow up to 5 feet long, or 1.5 meters, with unverified reports of individuals twice that length. It’s light brown with darker speckles and a paler belly. It lives in forested areas and spends most of its time hidden, waiting for an animal to happen by. Then it strikes! It eats pretty much anything it can catch, including frogs and rats, bats and birds, rabbits, lizards, other snakes, and even large insects. Its venom isn’t as potent as the golden lancehead’s but it’s still dangerous to humans, and unlike the golden lancehead, it can and does occasionally bite people.

The Martinique lancehead is endangered due to habitat loss and poaching. People are naturally afraid of the snake and will kill it when they can, when all it wants is to be left alone to eat animals like rats and other snakes that people don’t want around either. Hospitals in Martinique keep antivenin in stock to treat the 20 or 30 people who are bitten by a fer-de-lance every year. Most people are fine after receiving treatment, but those who can’t get to the hospital in time or who try to treat the bite at home sometimes die.

The Martinique lancehead gives birth to live young, as is the case for other fer-de-lance snakes. The eggs remain inside the mother until the babies hatch, at which point the mother delivers them and they slither away to live on their own.

Speaking of snakes having babies, let’s finish with a suggestion by Richard from NC, who sent me an article that was only published literally two days ago as this episode goes live. This is not about a snake that lives on an island, but it’s so interesting I wanted to include it. It’s about the Louisiana pine snake, which is not venomous, but which is one of the rarest snakes in North America.

The pine snake is a type of constrictor, and like other constrictors it can grow quite large. The largest individual ever reliably measured was over 5 and a half feet long, or 1.8 meters. It’s tan or yellowish in color with a darker brown pattern.

It lives in open pine forests and grasslands in parts of western Louisiana and east Texas, but even when it wasn’t so rare, hardly anyone ever saw one because it spends most of its time underground. It’s specialized to eat a little rodent called Baird’s pocket gopher, and when it’s not actually hunting the gopher, it hangs out in the gopher’s old burrows to stay cool and safe. In winter it hibernates in a gopher burrow, and there’s nothing the gopher can do about that.

Baird’s pocket gopher looks a little bit like a small guinea pig because of its large head, tiny ears and eyes, chunky body, and short legs. It has long claws that help it dig rapidly in the sandy ground it prefers. While the Louisiana pine snake mostly eats the gophers, it will also eat other small animals like frogs, rabbits, and bird eggs when it finds them. The snake is threatened by habitat loss, especially the problem of roads being built through its habitat. A lot of snakes are killed by cars while trying to cross the road. Since the snake usually only lays a few eggs a year, rarely more than five, it’s hard for populations to grow.

Fortunately, the Memphis Zoo in Tennessee is headquarters for a careful captive breeding program of the pine snake. And a few days ago, a baby snake hatched and is doing great! Hopefully more will hatch soon. The babies will be cared for until they’re big enough to be safe from most predators, and then they’ll be released into the wild. So far around 300 captive-born snakes have been released into the wild, increasing the Louisiana pine snake’s chance for long-term survival.

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