Episode 347: Two (Sort of) Spooky Amphibians

Thanks to Max for suggesting one of our slightly spooky amphibians this week!

Further reading:

New crocodile newt discovered in Vietnam

Further watching:

Brave Wilderness Giant Screaming Frog!

The new Halloween-y crocodile newt discovered in Vietnam [photo by Phung My Trung and taken from the article linked above]:

A smoky jungle frog:

A screenshot from the video linked above:

Show transcript:

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

It’s the end of September and you know what that means: we’re about to start Monster Month! This year I have so many awesome ideas for episodes that we’re starting monster month early, with a non-spooky episode about two sort of spooky-looking amphibians. Thanks to Max for suggesting one of the animals we’re about to talk about!

Instead of rating the monster month episodes on a spookiness scale from one to five ghosts, this year we’re rating them on a spookiness scale of one to five bats, which seems more appropriate. This episode is only one bat, meaning even our younger listeners shouldn’t find it scary.

But first, a quick correction. Thanks very much to Mary for catching a mistake I made in last week’s rhinoceros episode. I said that black rhinos can weigh 18 kilograms, when I should have said 1800 kilograms. 18 kg is about 40 pounds, so I think you can agree that I made a BIG mistake.

Now, on to the “spooky” amphibians.

Lots of amphibians live in southeast Asia, many of them never seen by scientists. In 2018, a team of scientists were studying crocodile newts in Vietnam when they discovered one that didn’t look like any of the many other crocodile newts that live in Asia. Since there are over 30 species known, with new ones being discovered all the time, including seven others from Vietnam alone, they suspected this might be a species new to science.

The new newt lives in high elevations in the central highlands in Vietnam, much farther south and in much higher elevations than the other known crocodile newt species. After the initial finding in 2018, the lead scientist, an amphibian and reptile expert named Phung My Trung (apologies because I probably pronounced his name wrong) spent four years searching for more specimens and learning about them before he described it as a new species.

One thing I love is that he was quoted as saying that the adult newts “were so beautiful that I was shaking and could hardly believe I was holding a live specimen in my hand.” And it is absolutely a gorgeous animal. It’s black with orangey-red markings on its back, lovely Halloween colors, and in fact the markings sort of look like the skull, backbone, and ribs of a cartoon skeleton. Females are bigger than males, and a big female can grow as much as 3 inches long, or 7.5 cm, from snout to vent, not counting its tail that’s almost as long as its body.

That’s pretty much all we know so far about this newt. Because it appears to have such a restricted range, it’s most likely endangered due to habitat loss and climate change, but now that we know it’s there, scientists and conservationists can work to keep it and its habitat safe.

Our other amphibian this week is one suggested by Max. Max, by the way, is an incredible artist who specializes in making reptiles and amphibians out of clay. Max asked specifically about the giant screaming frog, which definitely sounds like a Halloween-themed animal.

The giant screaming frog isn’t the actual name of the frog, or at least I couldn’t find a frog with that specific name. I think it’s from an awesome video posted in 2017. I’ll put a link in the show notes if you want to watch the video, which is a YouTube channel called Brave Wilderness. In the video, a man called Coyote Peterson catches a giant frog called the Smoky Jungle Frog. When he does, the frog makes this sound:

[screaming frog!]

That doesn’t actually sound all that spooky. But it is a warning call so I bet other smoky jungle frogs think it’s terrifying!

The smoky jungle frog lives in tropical and subtropical areas of Central and northern South America, where it lives in swamps, ponds, and even rivers, especially in rainforest environments. It’s a bit unusual in that males are larger than females, although only slightly. Both males and females grow about 7 inches long from snout to vent, or 18 cm, and are a mottled brown with darker spots and stripes that help them blend in with dead leaves on the forest floor.

The smoky jungle frog is nocturnal, and during the day it stays hidden in a burrow or buries itself in fallen leaves. At night it comes out to find food, and because it’s such a big, strong frog, it eats animals much larger than insects. It’s been observed eating small birds, especially baby birds, bats, snakes up to 19 inches long, or 50 cm, lizards, and sometimes even other frogs, including poison dart frogs. How embarrassing would that be if you were a bat, with strong wings and the amazing ability to echolocate, and you got eaten by a frog.

When a frog feels threatened, it has several ways to deter potential predators. It can make itself look even bigger by puffing its body up and standing up higher on its legs instead of sitting in a typical frog squat. It also secretes a toxin through its skin, which not only makes it really slippery but also makes it taste awful. It’s not dangerous to humans but can result in a painful burning sensation and rash if the toxin gets into a cut on the skin. If any of the mucus gets into your eyes, they will swell up painfully for hours.

The frog will also give its alarm call if something grabs it. Let’s listen to it again:

[frog ‘screaming’]

During mating season, the male develops little spikes near his wrists and on his chest. This helps him grasp a female without slipping off so he can fertilize her eggs as she lays them. The male uses his back legs to churn up the water and mix it with mucus and sperm to create a foamy nest for the female’s eggs, which protects the eggs from predators and makes sure they won’t dry out. The eggs hatch a few days later, and the tadpoles stay in the nest at first where they eat…well, they eat each other. The tadpoles that hatch first eat the other eggs, and the bigger tadpoles eat the smaller tadpoles. Soon, though, rain washes them out of the nest into open water, where they spend the next month or so eating small insects and algae until they metamorphose into little frogs that live on land. Unlike many frogs, the toes of the smoky jungle frog aren’t webbed since they don’t spend much time in the water.

So many times in this podcast I have to explain that an animal is endangered, so I’m happy to report that the smoky jungle frog is doing just fine. It’s a common animal throughout its range.

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 260: Danger! Newts!

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Thanks to Enzo for suggesting this week’s topic, newts from least dangerous to most dangerous!

Further reading:

One snake’s prey is another’s poison

The Corsican brook salamander is not toxic (photo by Paola Mazzei, from iNaturalist):

The smooth newt is a little bit toxic (photo by Fred Holmes and taken from this site) – this is a male during breeding season:

The Hong Kong warty newt has an orange-spotted belly and is toxic:

The chonky Spanish ribbed newt will stab you with its own toxin-covered bones (photo by Eduardo José Rodríguez Rodríguez, taken from this site):

Yeah maybe don’t touch the Japanese fire belly newt if you don’t need to:

Warning! Do not eat the California newt:

The safest newt to handle is this toy newt. I really want one:

Show transcript:

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

This week’s topic is a suggestion from Enzo, who wants to learn about newts “from least dangerous to most dangerous.” There are at least 60 species of newt known with more being discovered every year, but I’ll do my best to hit the highlights.

A newt is a type of salamander, specifically a semi-aquatic salamander in the subfamily Pleurodelinae. All newts are salamanders but not all salamanders are newts. Newts live throughout much of the northern hemisphere, including northern Africa and the Middle East, Eurasia, and North America.

Female newts lay their eggs in freshwater, usually attaching them to vegetation or in little crevices in rocks. A few weeks later, the eggs hatch into larvae with external gills. The larvae are called tadpoles like frog larvae, and they mostly eat algae and tiny insects. They metamorphose over several months just like frogs do when they develop from tadpoles, but where frogs develop their hind legs first, newt tadpoles develop front legs first. The newt tadpole finally absorbs its gills and grows lungs instead, at which point it emerges from the water as an immature newt called an eft. Efts are juvenile newts and live exclusively on land, although like other amphibians they have to keep their skin damp so you’ll usually find them in leaf litter and under rotting logs. Efts that live in North America return to the water when they become full adults, but most newts in other parts of the world stay on land the rest of their lives except during breeding season. Efts and adult newts eat worms, insects and insect larvae, slugs, frog tadpoles, and any other small animals they can catch.

The Corsican brook salamander is a type of newt that lives on the island of Corsica in the Mediterranean Sea. It grows about five inches long at most, or 13 cm, and is brown or olive-green, sometimes with a mottled pattern of orange or red on its back. It’s an exception to the rule that newts outside of North America usually live their adult lives on land. Not only does the Corsican brook salamander live in freshwater most of the time as an adult, it doesn’t even have working lungs. It spends most of its time in fast-moving streams and rivers in higher elevations, where it absorbs oxygen from the water through its skin.

As Enzo undoubtedly knows, many newts produce toxins. This is why it’s not a good idea to handle a newt, or any other amphibian for that matter, unless you’re absolutely certain it’s a species that’s not toxic. In most cases, a newt’s toxin won’t hurt you if it just touches your skin, but if it gets in a cut or if you have some of the toxin on your finger and then rub your eye or put your finger in your mouth, the toxin can make you really sick. Some newts are even deadly.

The Corsican brook salamander we just talked about is not toxic, so we’ll call it the least dangerous newt. The smooth newt, on the other hand, produces a relatively mild toxin. You’d have to actually eat a bunch of smooth newts to get sick from its toxins, and why are you eating newts at all? Stop that immediately and have a banana instead.

The smooth newt lives throughout much of Europe and parts of Asia. It grows just over 4 inches long, or 11 cm, and most of the time it’s brown with darker spots. The male also has a bright orange stripe on his belly. During breeding season, though, the male develops a wavy crest down his spine and brighter colors. Both males and females move into the water during breeding season, so both males and females develop tail fins on the top and bottom of their tails to help them swim.

The males of many newt species develop brighter colors and crests during breeding season to attract females. In the case of the Hong Kong warty newt, in breeding season the male develops a white stripe on his tail. He attracts the attention of females by wagging his tail in the water, where the white stripe shows up well even in dim light. The Hong Kong warty newt lives in Hong Kong and grows up to 6 inches long, or 15 cm. It’s brown with orange patches on its belly and its skin appears bumpy like the skin of an orange. If it feels threatened, it sometimes rolls onto its back and pretends to be dead, which not only may deter some predators, it shows off the bright orange markings on its belly. This signals to a potential predator that this newt is toxic, and another thing it does when it plays dead is secrete toxins from its skin. In other words, don’t bite this newt or touch it. It’s also a protected species in Hong Kong so you shouldn’t be trying to eat it anyway. Its eggs are toxic too.

Some newts deliver their toxins to potential predators in a way you might not expect. If an animal tries to bite the Spanish ribbed newt, it secretes toxins from special glands on its sides and then pushes the sharp points of its own ribs out through the tubercles where the poison glands are located. The pointed ribs become coated with toxins as they emerge and are sharp enough to stab a predator right in the mouth. The toxin causes severe pain when injected and can even cause death in small animals. The newt itself isn’t injured by this process, which it can do repeatedly whenever it needs to. Newts, like all amphibians, heal extremely quickly.

The Spanish ribbed newt lives in the southern Iberian Peninsula in Europe and Morocco in northern Africa. It’s larger than the newts we’ve talked about so far, growing up to a foot long, or 30 cm. It’s dark gray with rusty-red or orange spots on its sides, one spot per poison gland. It actually spends most of its adult life in the water and especially likes deep, quiet ponds and wells.

Finally, we’ve reached the most dangerous newt in the world. I’m nominating two newts for this honor because they both secrete the neurotoxin tetrodotoxin, which we’ve talked about before. It’s the same kind of toxin found in pufferfish and some frogs. The toxin can irritate your skin even if you only touch it, and if a little of the toxin gets into a scratch or cut, it can cause numbness, shortness of breath, and dizziness. If you accidentally swallow any of the toxin, you can die within six hours. There’s no antidote.

Our two most dangerous newts are the Japanese fire belly newt and the California newt. The Japanese fire belly newt grows about 5.5 inches long, or 14 cm, and lives in parts of Japan in ponds, lakes, and ditches. It has pebbly skin and is brown or black with red speckles, but its belly is bright orange or red. The California newt has slightly bumpy gray or gray-brown skin on its back but a bright orange or yellow belly. It can grow up to 8 inches long, or 20 cm. It lives in parts of California, especially near the coast and in the southern Sierra Nevada Mountains.

The reason the California newt has such a potent toxin is that its main predator, the common garter snake, has a great resistance to the toxin. Only the most toxic newts are more likely to survive if a garter snake grabs it, and only the most resistant snakes are more likely to survive eating it. It’s a predator-prey arms race that’s been going on for at least 40 million years, resulting in a newt that is boss fight level toxic to most predators but just barely ahead of the game when it comes to garter snakes. It’s likely that something similar has occurred with the Japanese fire belly newt.

If you live in the areas where these toxic newts also live, be especially careful with your pets. Keep your dog on a leash so you can be sure it doesn’t try to bite or play with one of these newts. Some people actually keep the Japanese fire belly newt as a pet, but obviously if you do this you need to be extremely careful, especially if you have pets or small children. Maybe you should get a toy newt instead.

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. If you like the podcast and want to help us out, leave us a rating and review on Apple Podcasts or Podchaser, or just tell a friend. 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!