Tag Archives: raven

Episode 333: Robins and Ravens

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Thanks to Liesbet, Simon, and Thea for their suggestions this week! Let’s learn about some birds!

Further reading:

Blue Tits and Milk Bottle Tops

Ravens parallel great apes in flexible planning for tool-use and bartering

Further watching:

A Raven Calling [this is a great video of a raven making all sorts of interesting sounds–I only used a tiny clip of it in the episode but it’s worth watching the whole thing]

The European robin:

The American robin and a worm that is having a very bad day:

A blue tit [photo By © Francis C. Franklin / CC-BY-SA-3.0, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=37675470]:

A blue tit about to get the cap off that milk bottle [photo from link above]:

The Eastern bluebird:

A raven:

An American crow:

Show transcript:

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

This week we have suggestions from Liesbet, Simon, and Thea, who suggested some relatively common birds that you may already think you know all about, but there’s lots to learn about them!

We’ll start with Liesbet’s suggestion, about the European robin and bluebird, and while we’re at it we’ll learn about the American robin and bluebird. The European and American birds are completely different species. The reason they have the same names is because when Europeans first started paying attention to the birds of North America, they needed names for the birds. The native peoples had names for them, of course, but the Europeans wanted names in a language they understood, so in a lot of cases they just borrowed names already in use at home.

Let’s start with the robin, which we also talked about way back in episode 81.

The European robin is a little bitty bird, only around 5 inches long, or 13 cm, with a brown back, streaked gray or buff belly, and orange face and breast. It has a short black bill and round black eyes. It eats insects, worms, berries, and seeds. The eggs are pale brown with reddish speckles.

It lives throughout much of Eurasia, but robins in Britain tend to be fairly tame, probably because they were traditionally considered beneficial in Britain and Ireland, so farmers and gardeners wouldn’t hurt them. In other parts of Europe they were hunted and are much more shy. European robins are also common on Christmas cards in Britain and Ireland, possibly because in the olden days, postmen used to wear red jackets. The postmen started to be called robins as a result, and since postmen bring Christmas cards, the bird robin became linked with card delivery and finally just ended up on the Christmas cards. Plus, their orange markings are cheerful in winter.

This is what the European robin sounds like:

[robin song]

The American robin is a type of thrush. It lives year-round in most of the United States and parts of Mexico, spends summers in much of Canada, and winters in parts of Mexico. It’s very different from the European robin. The European robin is tiny and round and adorable, while the American robin is big and always looks kind of angry. It grows around 10 inches long, or 25 cm. It’s dark gray on its back, with a rusty red breast, white undertail coverts, and a long yellow bill. It also has white markings around its eyes. Young birds are speckled. It mostly eats insects, worms, and berries.

If you see a bird on the ground, running quickly and then stopping, it’s probably a robin. Mostly the robin hunts bugs by sight, but it has good hearing and can actually hear worms moving around underground. You can sometimes see a robin with its head cocked, listening for a worm, before pouncing and pulling it out of the ground, just like in a cartoon.

American robin eggs are a light teal blue, so common and well-known that robin’s-egg-blue is a typical description of that particular color. In the spring after eggs hatch, the mother robin will carry the eggshells away from the nest to drop them, so predators won’t see the shells and know there’s a nest nearby. That’s why you’ll sometimes see half a robin eggshell on the sidewalk. It doesn’t mean something bad happened to the baby, just that the mother bird is doing her job. Both parents feed the chicks, and the parents also carry off the babies’ droppings to scatter them away from the nest.

This is what an American robin’s song sounds like.

[robin song]

Liesbet also wanted to learn about the European bluebird, more commonly called the Eurasian blue tit. We haven’t talked about it or the American bluebird before, even though they’re both beautiful birds.

The blue tit lives throughout Europe and parts of western Asia. It grows around 4 and a half inches long, or 12 cm, and has a bright blue crown on its head with blue on its wings, tail, and back. Its face is mostly white but it has a black streak that crosses its eye and a black ring around its neck. In fact, if you’re familiar with the blue jay of North America, the blue tit looks a lot like a miniature blue jay. It even has a little bit of a crest that it can raise and lower.

Because it eats a lot of insects and other small invertebrates, along with some seeds, the blue tit is an acrobatic bird. It will hang upside down from a twig to reach a caterpillar on the underside of a leaf, that sort of thing. It will also peel bits of bark away from a tree trunk to find tiny insects and spiders hiding underneath it. This habit leads it to sometimes peel bits off of people’s houses, like the putty that holds windowpanes in place. It also once led to the blue tit learning a surprising way to find food, and to learn about that, we have to learn a little bit about how people in the olden days got their milk if they didn’t own cows.

Back in the early 20th century, people used to get milk delivered every morning by a milkman. Refrigerators and ice boxes weren’t common like they are today, and most people didn’t have a way to keep milk cold. That meant it would go bad very quickly, so people would just order how much milk they needed in one day and when they got up in the morning, the milkman would have left the milk and other dairy products on the doorstep for the family.

The milk was always whole milk, also called full-fat, and as it sat in its bottles on the doorstep waiting for the family to wake up and bring the milk in, the cream would separate and rise to the top of the milk. Cream is just the fattiest, richest part of the milk. These days milk is processed differently so even if you buy whole milk, the cream won’t separate from it, and most milk sold today has already had most of the cream separated out. That’s why skim milk is called that, because the cream has been skimmed off the top. It’s sold separately as heavy whipping cream or mixed with milk as half-and-half. But back in the olden days, if you wanted to make whipped cream or clotted cream or some other recipe that calls for cream, you’d just skim the cream off yourself to use it.

The problem is, cream is so rich and full of protein that other animals learned to rob milk bottles, especially the blue tit. Birds can’t digest milk, naturally, since only mammals produce milk and are adapted to digest it, and even most adult mammals have trouble digesting milk. But cream contains a lot less lactose than the milk itself, and lactose is the type of sugar in milk that can cause stomach upset in adults. Blue tits learned that if they peeled the little foil cap off a milk bottle, they could get at the cream, and it became such a widespread behavior that each generation of blue tits became more adapted to digest cream.

These days, of course, most people buy their milk at the grocery store. The blue tits have had to go back to eating bugs and seeds.

This is what a blue tit sounds like:

[blue tit song]

The bluebird is a North American bird that also eats insects and other small invertebrates, along with berries and seeds. It grows around 7 inches long, or 18 cm. There are three species, the eastern bluebird and western bluebird, which look similar with bright blue above and white underneath with rusty red breast, and the mountain bluebird, which is blue almost all over and lives in mountainous areas of western North America. The bluebird is a type of thrush, meaning that it’s actually related to the American robin and used to be called the blue robin.

The bluebird spends a lot of its time sitting on a branch and watching for insects in the grass below. When it spots a grasshopper or beetle or spider or even a snail, it will drop down from its branch to grab it. It prefers open grasslands with trees or brush it can perch in, so it’s common around farmland. The mountain bluebird hunts like this too, but it doesn’t always bother to perch and will just hover above the ground until it spots a bug.

This is what an eastern bluebird sounds like:

[bluebird song]

Next, Simon and Thea wanted to learn about crows and ravens. The raven is another bird we covered a long time ago, in episode 112. I had a really bad cold the week of that episode and not only did I sound awful, I didn’t do a very good job with my research. I’m glad to revisit the topic and correct a few mistakes.

Crows and ravens look similar and are closely related, with both belonging to the genus Corvus. There are lots of species and subspecies of both, but let’s talk specifically about the American crow since it’s closely related to the hooded crow and the carrion crow found throughout Europe and Asia. Likewise, we’ll talk about the common raven since it’s found throughout much of the northern hemisphere.

The American crow can grow up to about 20 inches long, or 50 cm, with a wingspan over 3 feet across, or about a meter. Meanwhile, the common raven has a wingspan of up to 5 feet across, or 1.5 meters, and can grow up to 26 inches long, or 67 cm. Both are glossy black all over with large, heavy bills and long legs.

Crows and ravens both mate for life. Crows in particular are devoted family birds, with the grown young of a pair often staying to help their parents raise the next nest.

Both crows and ravens are omnivores, which means they eat pretty much anything. They will eat roadkill and other carrion, fruit and grain, insects, small animals, other birds, and eggs. They’re also extremely smart, which means a crow or raven can figure out how to get into trash cans and other containers to find food that humans think is secure.

Both also sometimes make and use tools, especially sticks that they use to dig out insects in places where their beaks can’t reach. But ravens in particular show a lot of tool use. Ravens sometimes throw pinecones or rocks at people who approach too close to their nests, and will even use sticks to stab at attacking owls. A few ravens have been observed to hold big pieces of bark in their feet while flying in strong winds, and they use the bark as a sort of rudder to help them maneuver. Other cognitive studies of ravens show that they have sophisticated and flexible problem-solving abilities where they can plan at least one step ahead, similar to great apes. Other corvids show similar abilities.

The raven can imitate other animals and birds, even machinery, in addition to making all sorts of calls. It can even imitate human speech. If a raven finds a dead animal but isn’t strong enough to open the carcass to get at the meat, it may imitate a wolf or fox to attract the animal to the carcass. The wolf or fox will open the carcass, and even after it eats as much as it wants, there’s plenty left for the raven.

Ravens also communicate non-vocally with other ravens. A raven will use its beak to point with, the way humans will point with a finger. They’ll also hold something and wave it to get another raven’s attention, which hasn’t been observed in any other animal besides apes.

The raven is much larger and heavier than a crow, and you can also distinguish a crow from a raven by their calls. This is what an American crow sounds like:

[crow call]

And this is what a raven sounds like:

[raven call]

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!

Episode 112: The Bullfrog and the Raven

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I am sick and sound like a frog, or possibly a raven, so here’s a croaky episode about both!

Thanks to Corbin Maxey of Animals to the Max and Simon for their suggestions!

A bullfrog:

A common raven:

A baby raven:

NOT a baby raven (it’s probably a corncrake):

Show transcript:

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

Guess who has a cold! That’s right, I do! If this is the first episode you’ve ever listened to, I promise I don’t ordinarily sound like this.

Because my voice is such a mess, let’s have a short episode this week and learn about two animals that sound kind of like I do right now: the bullfrog and the raven. Thanks to Corbin Maxey of the great podcast Animals to the Max who suggested frogs, and friend of the pod Simon who suggested ravens, both of them in response to my complaining on Twitter that I had a sore throat. Little did they know what I would sound like a few days after that tweet!

Let’s start with the bullfrog. The American bullfrog is a species of frog. You probably figured that out without me needing to tell you. It originally only lived in eastern North America, but it’s been introduced in many other parts of the world. The reason it’s been introduced elsewhere is that it’s raised as food—specifically, it’s raised for its hind legs, which are considered a delicacy. It’s also sometimes kept as a pet. Sometimes it escapes from captivity and sometimes it’s just released into the wild by people who don’t know any better. In many places it’s become an invasive species that outcompetes native amphibians.

The bullfrog is a big, heavy frog. It can grow up to eight inches long from nose to butt, or 20 cm, but the hind legs are much longer. It can also be up to 1.8 pounds in weight, or 800 grams. Because the bullfrog has such long, strong legs, it can jump up to ten times the length of its own body.

The bullfrog is olive green in color, sometimes with darker blotches or stripes. The belly is pale and the lower part of the nose along the upper edge of the mouth is often bright green. Males usually have yellow throats, or technically yellow gular sacs. This is the sac the male inflates in order to make his loud croak.

Male bullfrogs have territories in swampy areas that they defend from other males, but the territories aren’t very large, maybe 20 feet apart from each other at most, or 6 meters. The males tend to move around and gather in groups during the breeding season, though, which is usually spring and early summer. The males croak loudly to attract females, and sometimes wrestle each other to show who’s stronger.

The female bullfrog lays her eggs in shallow water with plenty of plant cover. If the temperature isn’t too warm or too cold, the eggs hatch in about five days into tadpoles. The tadpoles have gills and teeth, although at first they don’t use their teeth for anything. They eat algae and other tiny food at first, and as they grow bigger, they start catching larger food.

In warmer climates, the tadpole starts to metamorphose into a frog in a few months. In colder climates, the tadpole can take up to three years to grow into a frog.

A full-grown bullfrog will eat anything it can swallow, not just insects. It’ll eat mice and other rodents, bats, birds, other amphibians, crawdads, snails, fish, and small reptiles. It uses its long sticky tongue to catch its prey, then clamps its jaws shut so the prey can’t escape. If part of the prey is sticking out of its mouth, like a tail or leg, the frog uses its thumbs to cram the bits in. If the prey won’t quit struggling, the frog may jump into the water and swim around until the animal drowns. They should call them sharkfrogs, not bullfrogs.

A lot of animals eat bullfrogs, though, like alligators and various snakes, birds like herons and kingfishers, and river otters. I have personally seen a snapping turtle attack a bullfrog. That was creepy. Sometimes when something attacks a bullfrog, it will actually scream. This sometimes startles the predator enough that it lets go, and the bullfrog can escape. Bullfrogs show some resistance to snake venom too.

The bullfrog gets its name from its voice, not its size. It sounds like this:

[bullfrog croaking]

Next, hopefully I will not lose my voice before I finish talking about the raven. There are a number of different raven species but they all look similar. They’re big black birds with heavy bills and deep, raspy voices. They look like a buff crow. We’ll talk about the common raven today, which lives throughout the northern hemisphere: that means North America, Greenland, and most of Eurasia.

The common raven can grow up to 26 inches long, from bill to tail, or 67 cm, with a wingspan over four feet wide, or 150 cm. Its feathers are glossy black, with purplish or blue iridescence in sunlight. Young ravens look similar but are not as glossy. Sometimes you’ll see a picture online of a little black poof of a baby bird labeled as a baby crow or raven, but that’s a mistake. Baby ravens have sleek feathers, not downy feathers. I’ll put pictures in the show notes so you can see the difference.

The raven is an omnivore, which means it pretty much eats anything it can get. It will eat roadkill and other carrion, fruit and grain, insects, small animals, other birds, and eggs. It’s also extremely smart, which means it can figure out how to get into trash cans and other containers to find food humans think it secure. If a raven finds a good supply of food, it will call other ravens to join in the feast. This usually happens when a younger raven finds food and calls its friends, even if the food source is being guarded by a mated pair of adult ravens. Those pesky kids.

Ravens mate for life, but younger birds who haven’t paired off usually live in flocks. They’re devoted family birds, with grown young of a pair sometimes hanging around to help their parents raise the next nest. The raven lives a long time, up to 21 years in the wild and over 40 years in captivity.

The only animals that eat ravens are large owls and eagles, and even that’s rare. Ravens are big enough, strong enough, and smart enough to defend themselves.

Ravens are extremely intelligent birds. Research suggests that they may even have something approaching an actual language. They can certainly reason and deceive each other, and demonstrate empathy in their interactions with other ravens. They also use tools to help get food, and are well known to play with items, sometimes making toys out of twigs or other items to play with as a group. Young ravens in particular are curious and will steal shiny things.

Ravens can imitate other animals and birds, even machinery, in addition to making all sorts of calls. It can even imitate human speech much like parrots. If a raven finds a dead animal but isn’t strong enough to open the carcass to get at the meat, it may imitate a wolf or fox to attract the animal to the carcass. The wolf or fox will open the carcass, and even after it eats as much as it wants, there’s plenty left for the raven.

But ravens also communicate nonvocally with other ravens. A raven will use its beak to point with the way humans will point with a finger. Incidentally, dogs understand what pointing means, but wolves don’t. Just throwing that in there. They’ll also hold something and wave it to get another raven’s attention, which hasn’t been observed in any other animal or bird besides apes.

I will soon be reduced to communicating nonvocally if I don’t stop and rest my voice. So I’ll shut up and let you listen to a real raven:

[raven sound]

You can find Strange Animals Podcast online at strangeanimalspodcast.com. blah blah blah I’m not saying it this week. My throat hurts.

Thanks for listening! Next week hopefully I’ll be all better and sound like a human again instead of like a frog or a raven.

Episode 007: Strange Birds

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This week we look at three strange birds: a red-tailed Canadian raven that may or may not exist, the pied-billed grebe that definitely does, and New Zealand’s takahē.

A common raven. No red markings:

Here’s the Cryptodominion page with the red-tailed raven report.

Here’s Karl Shuker’s post about the red-tailed raven.

Precious smol baby pied-billed grebes riding on their mom or dad’s back:

The takahē, hooray!

Show transcript:

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

For this week’s episode we’ll look at three unusual birds, because birds are awesome. This is a re-record to improve audio quality and bring some information up to date.

It may be a tall tale, but a big red-tailed raven supposedly living in remote areas of British Columbia, Canada sounds oddly plausible. Loggers report that there’s a particular valley where huge ravens exist. They’re bigger than golden eagles but otherwise look like ordinary ravens except for their tails, which are reddish. They’re also nearly flightless. The loggers say the birds can be dangerous and will tear up campsites.

The only known raven found in Canada is the common raven. It’s much bigger and heavier than the crow, over two feet long, or 61 cm, including the tail, with a wingspan of over four feet, or 1.2 meters. The golden eagle, in contrast, can have a wingspan of nearly eight feet, or 2.4 meters, although the body length is not much more that of a raven’s.

The common raven is an intelligent, curious bird, black all over with a purplish sheen in the right light. It’s omnivorous and is happy to eat roadkill, food scraps found in unsecured garbage cans, and the eggs and hatchlings of other birds.

So could there be an unknown raven in British Columbia? I dug around online to see if I could find more details. In fact, I checked Allaboutbirds.com first since that’s a really good resource about North American birds. I wanted to see if there are any corvid species in North America that have red markings, but there aren’t. The only corvid in the world with red markings is the blue magpie, which has a rusty red head and wings. It’s a lovely bird, but it lives in Sri Lanka, and anyway its tail is blue.

I couldn’t find much online at all about the red-tailed raven story. It first appeared in 2012 or shortly before on a site called Cryptodominion. I’ll read the entry in its entirety, since it’s very short.

“British Columbian giant raven (Interior of B.C. NA): A piece of local folklore, the bush mechanics who worked in the interior of B.C. claim that here is a valley, rich in timber, which is populated by enormous raverns bigger than golden eagles. They say these ravens are dangerous animals, very opportunistic, and will not hesitate to tear someones camp apart. they are nearly flightless, and have much red in their tail plumage. These are obviously a specialized species of raven which developed in the isolation of this valley. However, if any introduced predators like dogs or cats make it there these ravens might become threatened.”

I learned about this story from zoologist Karl Shuker’s blog, Shukernature. He says that in 2012 a French reader emailed him asking him if he’d seen the entry and if he knew anything about the bird. He had never heard of the story before. Also in 2012, “The Corvid Enthusiast” posted about the Cryptodominion entry on an unexplained mysteries forum, asking if anyone in British Columbia had heard the story. One person did indicate they’d heard of it but gave no details, so I’m a bit skeptical of that reply. Responses from a few people from British Columbia indicate that the area is too populated and well explored to have any isolated valleys.

British Columbia is an enormous region, from the Pacific coast to the Rocky Mountains, from Vancouver’s mild climate to a northern border with the Yukon. The original entry says the valley is found in the interior of the British Columbia, which I take to mean as not coastal or on an island. I have absolutely no doubt there are pockets of wilderness in B.C. where any number of mystery birds might live.

So do I believe the red-tailed raven is a real bird? No. I think someone planted that story to see how far it would go. But if anyone wants to fund a birding expedition to British Columbia to look for the raven, I am standing by with my binoculars in one hand and my passport in the other.

Our second bird also lives in North America, although it’s just as common in South America and shows up occasionally in Europe and other places. The pied-billed grebe, also called a dabchick, isn’t an especially strange bird, but I’m including it just because I love it. I see them frequently while birding, especially in winter, and they’re so small and brownish-yellow that I frequently mistake them for ducklings at first glance.

They’re about a foot long from bill to tail, or 30 cm, but they sit so low in the water they look smaller. Actually they don’t even really have a tail. They just have some tufty feathers on their hind end.

Grebes aren’t ducks, although they do spend most of their time on the water. They don’t have webbed toes like ducks do. Instead, they have lobed toes but you probably won’t ever see them because grebes don’t like to get out of the water. Their legs are set so far back on their bodies that they don’t balance well while walking. If they have to, they’ll fly, but again, they’d rather just stay on the water. Some populations migrate, especially if they live where ponds freeze in winter, but populations in more temperate climates stay year-round.

They prefer freshwater ponds and small lakes with plenty of cover, like cattails, reeds, and other vegetation. They’re diving waterfowl, which means they spend a lot of time underwater, catching fish, frogs, insects, and crustaceans like crawdads, which they crush with their blunt bills. They also eat their own feathers. That sounds weird, but it’s actually something all grebes do. They even feed feathers to their babies. The feathers help keep pieces of bone or shell from traveling from the stomach to the intestines. Instead, the feathers and hard pieces of non-food form pellets which the bird horks up safely.

Baby grebes are the smallest of the small. They can’t swim right away like ducklings can, which you’d think would be a problem since grebes build floating nests on vegetation. But (you’ll love this) they ride around on their parents’ backs for a few weeks until they learn to swim on their own.

Oh, and the most interesting thing about the pied-billed grebe? It can sink. The first time I saw this happen, I really didn’t believe my eyes. I was birding along the edge of a slow-moving river, looked down at the water through the trees, and saw two tiny duck-like birds which promptly vanished into the water as though they’d been abducted by a submerged alien. One second they were there, the next they were literally just gone. The pied-billed grebe does this by trapping water in its feathers, which gives it incredible control over how far down it sinks and may also reduce drag while it swims underwater.

Now let’s talk about another bird, this one halfway around the world, definitely real, and completely flightless. The takahe was a chicken-sized bird with a greenish back, iridescent purple head and neck, and heavy red bill and legs. It lived in New Zealand’s swamps and grasslands. The white settlers introduced red deer, cats, ferrets, stoats, hunting for sport, and all the usual things. In 1898 four birds were caught…and that’s the last anyone saw of the takahe.

Of course there were rumors that the birds survived. There always are. But as with so many other animals driven to extinction by habitat loss, hunting, and introduced animals, hope for a surviving population of takahe gets smaller every year.

Wait a minute.

I’ve just been handed a piece of paper by my research assistant, who I just now invented. It says here that the takahe was discovered alive and well in the Murchison Mountains on November 20, 1948!

The takahe now lives in the Murchison Mountains and on five small islands, chosen as habitats because they’re free from predators. The birds mate for life and breed slowly, but they can live up to 25 years in captivity. They mostly eats seeds, insects, and the tender parts of grass stems, but one bird was caught eating a duckling. I like to imagine it wore a really guilty expression while chowing down.

Takahe chicks are fuzzy and gray with yellowish legs. The adults are about 20 inches tall, or 50 cm.

For a long time it wasn’t clear if the birds would even survive. In 1981 there were only 118 known individuals. The population now stands at over 400 with a careful breeding program in place to keep the species as genetically diverse as possible. When I first put together this episode in spring of 2017, there were only just over 300 takahes, so that’s a big improvement in only three years.

There’s not a lot more to say about the takahe. I’m just really happy that sometimes there are persistent rumors about an extinct species’ survival because it really has survived. Stay strong, takahe. Eat ducklings if you have to.

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

Thanks for listening!