Strange Animals Podcast

Further reading:

Identifying the beasts in Caesar’s forest

Reindeer:

Show transcript:

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

After the glaciers retreated from Europe at the end of the last ice age, around 11,000 years ago, forests grew wherever there was enough soil to support a tree. As these new forests spread, they joined forests that had survived the glaciations. By the time ancient Romans were writing about the things they encountered while exploring western Europe, around 2,000 years ago, the forest stretched across much of the continent and was considered a wild, dangerous place. They called it the Hercynian [her-SIN-ian] forest and it was supposed to be full of peculiar animals.

An account of the forest appears in the book Commentarii del Bello Gallico, the first edition of which was published just over 2,000 years ago in 49 BCE. It was written by Julius Caesar, or at least he was involved in it even if he didn’t actually write it personally, since it was about his military campaigns. In one section of the book he discusses the Hercynian forest and three remarkable animals that lived in it.

The first was called the uri, which were supposed to look like bulls but were almost the size of elephants, and were incredibly aggressive. This is probably the same animal often called the aurochs, which we talked about in episode 58. The aurochs was probably the wild ancestor of the domesticated cow and could stand almost six feet tall at the shoulder, or 1.8 meters. It had already gone extinct in most places 500 years before Caesar wrote his book, but it still lived in parts of Europe.

The second animal is a lot harder to identify. The alces looked like a big goat that either didn’t have horns or had very short ones, but its legs didn’t have joints. If an alces fell over, it couldn’t get up again. Caesar explained that hunters used this to their advantage. Because the alces couldn’t lie down at night, it would sleep by propping itself against a tree. The hunters would note which tree an alces preferred, and during the day they’d cut a notch in the trunk. When the alces leaned against it at night to sleep, the tree would topple over, taking the animal with it. The waiting hunters would then be able to just stroll up and kill the alces.

Naturally, this story doesn’t make any sense. All tetrapods have jointed legs. But the story of an animal without joints in its legs crops up in various stories from around this time, including the part where hunters cut a notch in a tree trunk to knock the animal over. It’s a story once told about the elephant and the Eurasian elk, among others, and the alces was probably based on the Eurasian elk. That’s the Eurasian population of the animal called the moose in North America. Because the story specifies that the alces either didn’t have horns or had very small ones, it’s possible that Caesar based his story on the female elk, which doesn’t have antlers.

Incidentally, we’re so certain that the alces was the same animal as the Eurasian elk that its scientific name is actually Alces alces.

Finally, the Hercynian deer was likewise large and had a single horn. A translation of the passage states: “There is an ox with the shape of a deer; projecting out of its forehead, in the middle, between the ears, is a single horn, which is both longer and more upright than those horns we are used to seeing.” Other sources that talk about this animal also say that the horn branched at the end, and Caesar notes that both males and females had these horns.

This gives us a big clue as to what animal might have inspired the account. Unlike most deer, both male and female reindeer have antlers. Unlike caribou, the North American reindeer species, the European reindeer often has relatively long and straight main shafts on its antlers that then enlarge at the end in what’s called a palmate structure. That basically means it’s shaped like a hand.

But reindeer have two antlers, not one. It’s possible that the story of the Hercynian deer was inspired by the unicorn legend, which was based on the rhinoceros. It might also have been inspired by Caesar sighting a reindeer that had dropped one antler but hadn’t yet lost the other one, since like other deer, reindeer shed their antlers and regrow them every year.

The reason Caesar wrote about the animals of the Hercynian forest in the first place was to underline how strange and uncivilized the people living in the area were. The people in question are what today we would call Germans. Caesar stresses that all these animals are ones never seen anywhere else, and he might easily have added exotic details from other fabulous animals to make these animals seem extra weird.

These days most of the Hercynian forest is long gone, chopped down for people to turn into farmland and towns. While the Eurasian elk and the reindeer are still around, they no longer live as far south as Germany. The last aurochs went extinct in 1627 in Poland. But the German people are doing just fine, and they’re a lot more civilized than Caesar gave them credit for 2,000 years ago.

Thanks for your support, and thanks for listening!

This week let’s look at the work of a really astonishing number of spiders!

Further reading:

Megaweb!

Some of the webs:

Show transcript:

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

Baltimore, Maryland is a city in the northeastern United States, in North America, with a population of 2.8 million people. In 1993 a new wastewater treatment plant was built called the Back River Wastewater Treatment Plant, which filters water through big sand beds to trap any particles remaining in it after it’s been filtered and treated in other facilities. The plant consists of 48 big sand beds with a corridor down the middle, and in order to keep the sand beds as clean as possible, the whole area has a big metal roof over it held up with steel columns. It doesn’t have walls, though, just a roof. The whole thing covers four acres, or 1.6 hectares, which I think is a metric term. It’s just over 16,000 square meters. It’s big, in other words, and the roof is pretty tall, up to 24 feet high over the walkway, or 7.5 meters.

Obviously, I’m telling you about this place in detail because of an animal that got into the water treatment plant and caused a lot of alarm. It wasn’t a big animal like a bear, though. It wasn’t even a dangerous animal. It was, in fact, a really small animal that’s mostly harmless to humans, various species of orbweaver spider. The problem wasn’t the spider itself but just how many spiders were in the water treatment plant.

The plant had always had problems with lots of orbweavers, but in 2009 there were so many spiders that the workers were worried for their safety. In late October 2009, the managers called for help about “an extreme spider situation.” The problem was way beyond anything that an ordinary pest control business could deal with, so the city put together a team of arachnologists, entomologists, and experts in urban pest control to figure out the best course of action.

The team didn’t just charge in, say, “Wow, that’s a lot of spiders, let’s hose the whole place down.” They were scientists and studied the situation methodically. They consulted the architectural plans of the plant to determine just how much volume was available under the roof, they took samples of the webs and stored them for study, they took over 300 photos, and basically they got as much data as they could.

There were so many spiders that their webs blended together into thick mats that filled almost every space the spiders could reach. These cobweb mats were attached to the rafters, the walkways, everywhere, with the older mats starting to detach and fray. Light fixtures hung down from the tallest point of the roof that were 8 feet long, or 2.44 meters, and there were so many webs attached to them that they were pulled out of alignment. And all the webs were filled with spiders.

The spiders in the web samples were removed and preserved, then examined to see what species they belonged to. The team identified specimens from nine genera in six families, but most of the spiders caught were the species Tetragnatha guatemalensis. This is a type of long-jawed orbweaver native to North and Central America. Females are much larger than males, with a legspan up to 2 inches across, or about 5 cm. Long-jawed orbweavers have long, thin bodies, and one of the ways it hides is by stretching out on a blade of grass or a twig with its legs out straight. It especially likes marshy areas, such as in the rafters above 48 giant sand beds full of water.

A conservative estimate of the number of spiders in the Back River Wastewater Treatment Plant in the first week of November, 2009 was 107 million. 107 million spiders! Since a big percentage of the spiders were newly hatched, there were probably a lot more in the facility than the scientists estimated from the samples they took, so there might easily have been several hundred million spiders total. The sheets of webbing in the ceiling covered an estimated 2 acres total, or about 8,000 square meters, while the cloud-like masses of webbing in other areas was about half that size and would have filled 23 railroad boxcars.

The really interesting thing is that orbweaver spiders are usually solitary. Spiders may build webs near each other, but not usually like this. But these orbweavers lived in a place protected from wind and weather, and close to water, which attracted lots of midges and other small insects, and the presence of humans probably kept a lot of potential spider predators away, like birds. Life was good for these spiders and the scientists observed that they weren’t acting aggressively to each other, even when they were of different species.

After studying the water treatment plant and its spiders, the team came to several conclusions. Since the spiders are harmless to humans, and are doing a really good job controlling the midge population, the scientists decided that pest control was not necessary and would even be a bad idea since the pesticides would inevitably get into the water. Instead, they recommended that web removal be implemented as a normal course of action when the webs started building up too much. They even suggested that the workers should be proud of their record-breaking webs, and that the plant was an ideal site for scientists to study the spiders in detail.

Thanks for your support, and thanks for listening!

DRAMA! Bird drama! Here are some further-reading links if you want to verify that I’m not vilifying anyone:

Buff-breasted Buttonquail: An image claimed to be of this species revealed

Buff-breasted Buttonquail: Smoke & Mirrors

A review of specimens of Buff-breasted Button-quail Turnix olivii suggests serious concern for its conservation outlook

A painted button quail:

Show transcript:

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

Back in episode 136 we talked about the button quail, because that episode was about tiny animals and the button quail is really tiny. But let’s revisit the button quail this month, because we have a mystery associated with a particular species of button quail.

Button quails generally live in grasslands and are actually more closely related to shore and ocean birds like sandpipers and gulls than to actual quails, but it’s not very closely related to any other living birds. It can fly but it mostly doesn’t. Instead it depends on its coloring to hide it in the grass where it lives. It’s mostly brown with darker and lighter speckled markings, relatively large feet, and a short little tail. It eats seeds and insects along with other small invertebrates.

The button quail is especially interesting because the female is more brightly colored than the male, although not by much. In some species the female may have bright white markings, while in others her speckled markings are crisper than the males. The female is the one who calls to attract a male and who defends her territory from other females. The female even has a special bulb in her throat that she can inflate to make a loud booming call.

The male incubates the eggs and takes care of the chicks when they hatch. Baby button quails are fuzzy and active like domestic chicken babies but they’re only about the size of a bumblebee. In many species, as soon as the female has laid her eggs, she leaves them and the male and goes on to attract another male for her next clutch of eggs.

The various species of button quail live in different areas, including Africa, Asia, and Australia. The species we’re talking about today is the buff-breasted button quail, which is native to one small area of Queensland, Australia. It grows about 9 inches long, or 23 cm, which is big for a button quail, most of which are closer to the size of sparrows, and it’s reddish-brown with darker and lighter speckles. It’s critically endangered due to habitat loss and introduced animals like cats and cattle. There are only an estimated 50 individuals alive today.

But that’s only an estimate, because no one has actually for sure seen a buff-breasted button quail since 1922. Also, I’m going to call it the BBBQ from now on because that name is hard to say.

The 1922 specimen was shot by a naturalist who was collecting specimens for a museum, which was regrettably common at the time and led to a lot of endangered species being driven to extinction. The bird was already rare in 1922 and that was the last anyone saw of it until 1985, when someone reported seeing one. People flocked to the area in hopes of spotting it, but while there were lots of sightings, no one got a good picture of a BBBQ. All the pictures, and all the recordings of its calls, turned out to be of another species of button quail, a very similar bird called the painted button quail.

It’s been 100 years since the bird was last seen, so while we have lots of museum specimens, we don’t have any modern sightings. That means two things. Either the buff-breasted button quail is probably extinct…or it never actually existed in the first place.

There are two other species of button quail that live in the same areas where the BBBQ is found, the painted button quail and the brown quail. They’re smaller but otherwise look very similar, especially the painted button quail. Maybe people were mistaking larger individuals of painted button quails as a different species.

In 2018, a team of scientists from the University of Queensland conducted a search for the BBBQ. All they found were painted button quails. But they discovered something surprising that had never been documented before. During the breeding season, the female painted button quail’s feathers are much more reddish-brown, while the rest of the year the feathers on her back are more gray-brown.

The team also studied as many BBBQ skins as they could track down from museums, where they learned something else surprising. It turns out that it’s not any larger than the painted button quail, which grows up to 8 inches long, or 20 cm. So the birds are the same size and during part of the year, they have almost identical plumage. Hmm.

That doesn’t mean the buff-breasted button quail never existed. One very distinctive difference between the painted and the buff-breasted species is eye color, with the former having red eyes and the latter having yellow. As far as I know a genetic study hasn’t been carried out on the museum specimens, but it’s likely that at least some of the specimens—maybe all of them—really are BBBQs. Scientists and bird enthusiasts are still looking for the bird, and that has led to a strange controversy.

In early 2022, a naturalist named John Young published a photo on Facebook of what he said was a male buff-breasted button quail on a nest, a photo taken by a camera trap in a secret location. The location had to be secret so that no one would try to find the birds and scare them away or damage a nest. Young said he had 16 other photos of BBBQs but wasn’t going to share them until he was ready to publish his findings. He was also raising money to continue his studies at the site.

Another naturalist thought there was something fishy about the photo. He discovered that the picture is actually a cropped and flipped photo of a painted button quail bird and nest reportedly taken at a different site—published in 2018 by John Young himself and labeled by him as a painted button quail. Young had reused one of his own photos and assumed no one would notice.

But it gets worse. Back in 2013, Young got photographs of another extremely rare Australian bird, the night parrot. One day we’ll have an episode about it. It was such a big deal that he was offered a job by the Australian Wildlife Conservancy, or AWC, to study the night parrot and the buff-breasted button quail. He documented sightings and produced photos of both birds, but he didn’t stay in that job too long. That’s because some people started getting suspicious of his parrot photos. After an inquiry into the night parrot photos, the AWC concluded that the eggs in a photo of a night parrot nest were probably fake.

And Young’s dubious photos go back even farther. In 2006 he claimed to have discovered a new species of parrot in Queensland, but while initially the Queensland government supported learning about the new species, it withdrew its support when the photo turned out to be…suspicious. It looked like Young had altered the coloration of a bird to make it look like a new species. When an expert requested the original photographs, Young said he’d deleted them.

More recently, the 2018 painted button quail photo and the supposed 2022 BBBQ photo were examined by a forensic photography expert. Young had removed the metadata from both so no one could tell where they were taken, but there’s a little white stone in both pictures that’s identical, along with many other identical details.

The problem with fake sightings and photographs is that it’s actually making things worse for the buff-breasted button quail. The AWC and other conservation groups are trying to get the bird listed as endangered, which means funding for research and conservation. Now all that is in jeopardy because it’s not clear if there have actually been any sightings of the bird at all.

Hopefully the buff-breasted button quail is still around and someone will get genuine photos of it soon so it can be protected and studied. That’s assuming it’s a real bird in the first place.

Thanks for your support, and thanks for listening!

This week let’s learn about some blue frogs!

Further reading:

Scientists make chance discovery of rare blue skin mutation in Kimberley magnificent tree frog

White’s True-Blue Green Tree Frog

Show transcript:

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

When most of us draw a frog, we reach for the green markers, because most frogs are green. That’s true of the magnificent tree frog, also called the splendid tree frog, which is fairly common in the Kimberley region of western Australia. It grows just over 4 inches long, snout to vent, or about 10 and a half cm, and lives in rocky areas. It spends the day hiding in rock crevices, holes in trees, or sometimes in people’s houses, and it comes out at night to hunt for insects and other small invertebrates.

From the name, you might imagine that this is an especially pretty frog, and it is. It’s mostly bright green on top and yellow to white underneath, and it has tiny yellow spots on its head and back. It looks like it has an olive green cap on its head, but that’s actually a large parotoid gland, a skin gland common in frogs and toads that secretes neurotoxins. Most frogs don’t have a parotoid gland at all, and in ones that do you typically will barely notice it, but the magnificent tree frog’s covers the entire top of its head almost to its nostrils and down onto its back.

The skin color of a frog depends on its chemical makeup. Melanophores make black and brown colors, xanthophores make yellow. Blue is different, since it’s not a color that’s actually found in skin pigments. Instead, a green frog’s skin contains iridophores that reflect blue light waves, the same way a bird’s feathers show blue. The combination of yellow and blue makes green, and the addition of melanophore pigments determine how dark or bright the green is.

In July of 2024, two land managers were working in the Charnley River-Artesian Range Wildlife Sanctuary. They were in a workshop when one of them noticed a magnificent tree frog sitting on a bench, not that unusual of an occurrence–except that this frog wasn’t green. It was blue!

The condition is called axanthism, where the yellow pigments in the frog’s skin don’t show up the way they should. Most of them time axanthism in frogs means the animal has little patches of blue or bluish coloration, but this specific frog was blue just about everywhere it should have been green. Its parotoid gland was still olive green and it had yellow on its feet, but mainly it was a very attractive dark blue.

The land managers were stunned. They took photos and sent them to pretty much everyone, and frog experts and ecologists hurried to examine the blue frog. But they decided not to keep the frog in captivity. It was released back into the wild to live out its blue froggy life normally.

Some frogs are naturally blue, like some poison dart frogs of South America. The blue poison dart frog’s legs are dark blue and its body a lighter blue with black spots. It grows less than two inches long, or about 4.5 cm. Poison dart frogs collect toxins in their bodies from some of the toxic insects they eat, and the bright coloration signals to predators that this frog will make you really sick if you eat it.

Axanthism is rare but not all that uncommon in frogs. About the same time that the blue magnificent tree frog was hopping into the workshop in Australia, two little girls playing around a pond in Nova Scotia, Canada found a teal-blue frog. Ironically, the frog is actually called the green frog and it’s ordinarily a dark olive-green all over. The girls named the frog Bluey and released it back into the pond. Another blue green frog was found in New Hampshire, in the United States, also in July 2024. In June 2024 a forest ranger spotted a northern leopard frog in Washington state that had splotches of light blue on its head and back. In May of 2024 a light blue Japanese tree frog was found by a couple on a walk.

The Australian green tree frog is closely related to the magnificent tree frog, although it doesn’t have a parotoid gland hat. It’s mostly green with a white or pale gray belly. It’s sometimes called the dumpy tree frog because it’s a little chonk. Actually, for a frog it’s a pretty big chonk, up to 4 and a half inches long, or over 11 cm. It’s also sometimes called White’s tree frog after John White, who described it in 1790. It was the first Australian frog that was ever scientifically described. But that leads us to a little mystery.

John White named the frog Rana caerulea. Its current scientific name is Ranoidea caerulea. But “caerulea” refers to the color blue, not green, as in cerulean blue.

John White collected the frog in 1788, preserved it in alcohol, and finally described it two years later. He refers to it in his writing as a blue frog and the illustration accompanying it shows frogs that are actually blue. But this frog is supposed to be green!

The main suggestion for why a famously green frog was initially described as blue is that the alcohol that White used to preserve the frog’s body actually destroyed the yellow pigment in its skin. This is something that does sometimes happen with frog specimens in museums. But it’s also possible that White ended up with a blue specimen, much like the blue magnificent tree frog we talked about earlier. He wouldn’t have known that the blue frog had a rare color mutation. That would explain why he referred to the frog as blue and gave it a name that means blue.

That might also explain why White described the Australian green tree frog first. Maybe he just thought it was pretty. Everyone likes the color blue.

Thanks for your support, and thanks for listening! I’m at Dragon Con this weekend, where who knows, I might actually see a blue frog. Anything is possible at Dragon Con.

Further reading:

Parallels for cetacean trap feeding and tread-water feeding in the historical record across two millennia

Haggling over the Hafgufa

Many renditions of the hafgufa/aspidochelone:

Show transcript:

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

Back in the olden days, as much as 1700 years ago and probably more, up through the 14th century or so, various manuscripts about the natural world talked about a sea monster most people today have never heard of. In ancient Greek it was called aspidochelone, contracted to aspido in some translations, while in Old Norse it was called the hafgufa. But it seemed to be the same type of monster no matter who was writing about it.

The animal was a fish, but it was enormous, big enough that it was sometimes mistaken for an island. When its jaws were open they were said to be as wide as the entrance to a fjord. A fjord is an inlet from the sea originally formed by glaciers scraping away at rocks, and then when the glaciers melted the sea filled the bottom of what was then a steep valley. I’m pretty sure the old stories were exaggerating about the sea monster’s mouth size.

The sea monster ate little fish, but it caught them in a strange way. It would open its mouth very wide at the surface of the water and exude a smell that attracted fish, or in one account it would regurgitate a little food to attract the fish. Once there were lots of little fish within its huge mouth, it would close it jaws quickly and swallow them all.

Generally, any sea monster that’s said to be mistaken for an island was inspired by whales, or sometimes by sea turtles. The hafgufa is actually included in an Old Norse poem that lists types of whales, and the aspidochelone was considered to be a type of whale even though the second part of its name refers to a sea turtle. So whatever this sea monster was, we can safely agree that it wasn’t a fish, it was a whale. Up until just a few centuries ago people thought whales were fish because of their shape, but we know now that they’re mammals adapted to marine life.

But the hafgufa’s behavior is really weird and doesn’t seem like something a whale would do. We’ve talked about skim feeding before, where a baleen whale cruises along at the surface with its mouth held open, until it’s gathered enough food in its mouth and can swallow it all at once. But whales aren’t known to hold their mouths open at the surface of the water and just sit there while fish swim in. At least, they weren’t known to do this until 2011.

In 2011, marine biologists studying humpback whales off Canada’s Vancouver Island in North America observed some of the whales catching herring and other small fish in an unusual way. The whales would remain stationary in the water, tails straight down with the head sticking up partly out of the water. A whale opened its mouth very wide and didn’t move until there were a lot of fish in its mouth, which it then swallowed. Soon after, another team of marine biologists studying Bryde’s whales in the Gulf of Thailand in South Asia observed the same activity when the whales were feeding on anchovies at the surface of the water.

The term for this activity is called trap feeding or tread-water feeding, and at first the scientists thought it was a response to polluted water that had caused the fish to stay closer to the surface. But once the two teams of scientists compared notes, they realized that it didn’t appear to have anything to do with pollution. Instead, it’s probably a way to gather food in a low-energy way, especially when there isn’t a big concentration of fish in any particular spot, and when researchers remembered the story of the hafgufa, they realized they’d found the solution to that mystery sea monster.

The only question was whether the accounts were accurate that the hafgufa emitted a smell or regurgitated food to attract fish. Further observation answered that question too, and it turns out that yes, the old stories were at least partially right. The smell has been compared to rotten cabbage, but it isn’t emitted by the whale on purpose. It’s a smell released when phytoplankton is eaten in large numbers, whether by fish or whales or something else, and it does attract other animals.

As for the regurgitation, this is always something that happens to some degree when a baleen whale feeds. The whale fills its mouth with water that contains the fish and other small animals it eats, and it presses its huge tongue upwards to force the water through its baleen, which acts as a sieve. Whatever’s left in its mouth after the water is expelled, it swallows. But baleen is tough and fish are small and delicate in comparison. Often, fish and other small animals get squished to death against the baleen, and parts of them are expelled with the water. This creates a sort of yucky slurry that could be interpreted as a whale regurgitating food to attract more fish. The scientists think that fish are mainly attracted not to any smell or potential food in the water, but to the supposed shelter offered by the whale’s giant mouth.

It appears that trap feeding is a fairly rare behavior in whales, but one that’s been around a lot longer than the last few years. It’s also possible that because whaling drove many species nearly to extinction and whale numbers are only just starting to recover, until recently whales didn’t need to use this feeding strategy. It seems to be used when a preferred food is widely scattered so that chasing after the fish isn’t worth the energy cost, and that’s more likely to happen when there are a lot of whales around.

It’s amazing that this type of feeding strategy has been identified in two different species of whale, and it’s even more amazing that it matches up so well with ancient accounts. It’s easy to assume that in the olden days, people were kind of stupid, but people back then were just as intelligent as people now. They just didn’t have our technology and modern knowledge. They were often extremely observant, though, and luckily for us, sometimes they were able to write their observations down in books that we can still read.

Thanks for your support, and thanks for listening!