Tag Archives: vultures

Episode 326: The Harpy Eagle and Friends

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Thanks to Eva and Anbo for suggesting the harpy eagle!

Further reading:

Crested Eagle Feeding a Post-Fledged Young Harpy Eagle

Harpy eagle with a food [By http://www.birdphotos.com – Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=3785263]:

The harpy eagle has great big feet and talons:

The harpy eagle with its feather crown raised [photo by Eric Kilby]:

The New Guinea harpy eagle looks similar to its South American cousin [By gailhampshire from Cradley, Malvern, U.K – New Guinea Harpy Eagle. Harpyopsis novaeguineae, CC BY 2.0, https://commons.wikimedia.org/w/index.php?curid=86187611]:

Ruppell’s griffon vulture:

Show transcript:

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

We’ve been talking about a lot of mammals lately, so let’s have an episode about birds. Anbo suggested the harpy eagle not too long ago, and a much longer time ago Eva suggested the harpy eagle and other raptors.

The word raptor can be confusing because it refers to a type of small theropod dinosaur as well as a type of bird. When referring to a bird, the term raptor includes eagles, hawks, vultures, owls, and other birds of prey. And that includes the harpy eagle.

The harpy eagle lives throughout much of Central and South America, although not as far south as Patagonia. It has a wingspan up to about seven feet across, or over 2 meters, and like other raptors, females are larger than males. This isn’t an especially big wingspan for an eagle, but that’s because the harpy eagle hunts in forests and needs short, broad wings that allow it to maneuver through branches.

The harpy eagle is a beautiful bird. It has a light gray head and darker gray or black body, and is white underneath with delicate black stripes on its leg feathers, with broader stripes on its tail and wings. It has a black ring around its neck, huge yellow feet with enormous talons, and a black bill. Each talon, which is the term for a raptor’s claws, can be over 5 inches long, or 13 cm, while its feet in general are bigger than a grown man’s hand, even if the man has especially big hands.

Most striking of all is the harpy eagle’s crest, also sometimes referred to as a crown. The crown is made of long, rounded feathers and most of the time they don’t show very much. When a harpy eagle is alarmed, it raises the feather crown and poofs out the feathers on its face, which makes its head look bigger and sort of owl-shaped.

The harpy eagle mostly lives in lowland rainforests. It mates for life and doesn’t have babies every year. Every two or three years a harpy eagle pair will build a huge nest out of sticks in the top of the tallest tree they can find. The female lays two eggs, which the parents care for together. The female spends most of her time incubating the eggs while the male brings her food, although he will also take a turn incubating while she goes out to stretch her wings and do a bit of hunting herself. When the first egg hatches, the parents bring the baby lots of food and give it lots of attention–but they ignore the other egg at that point, which usually doesn’t hatch as a result. A harpy eagle chick is all white at first, and although it can fly at around 6 months old, its parents will keep feeding it for almost another year.

The harpy eagle is increasingly threatened due to habitat loss and poaching. Because it’s such a big bird, many people shoot it because they think it’s dangerous to livestock or children. But it mostly eats monkeys, sloths, kinkajous and coatis, iguanas, and other medium-sized animals. It’s rare that it attacks livestock since it mostly hunts within the tree canopy for arboreal animals. If your lambs and chickens are sitting on tree branches, you already have a bigger problem than harpy eagles eating them.

A captive breeding program has been started in various zoos around the world, while conservationists work to protect the harpy eagle’s natural habitat so that individuals can be released back into the wild.

We don’t actually know all that much about the harpy eagle, but we know even less about its close relation, the New Guinea harpy eagle. It resembles the harpy eagle but instead of being mostly gray and white, it’s mostly brown and cream in color. It has longer legs and tail but is smaller overall than the harpy eagle, with a wingspan closer to 5 feet across, or 1.5 meters. It has a smaller crest than the harpy eagle too.

Like its South American cousin, the New Guinea harpy eagle hunts in forests, especially rainforests, and spends most of its time perched in a tree, watching for small animals to happen by. Sometimes it will shake a branch to startle any animals in the area to run or fly away, at which point the eagle flies after them. It will even climb around in a tree and poke around in any potential hiding places it finds. It eats tree kangaroos, possums, and other small to medium-sized mammals, but it also eats a lot of birds and reptiles.

While it’s closely related to the harpy eagle, the New Guinea harpy eagle is placed in a different genus. This is also the case for another closely related bird, the crested eagle, which lives in parts of South America. It’s a little smaller than the harpy eagle of South America, with a wingspan of not quite 6 feet across, or 1.8 meters, with a black mask marking over its eyes and a black spot on its crest. Other than that it’s mostly gray.

The two species look enough alike that sometimes people confuse the crested eagle for a young harpy eagle where their ranges overlap. But in at least one documented case, the birds seemingly got confused too.

In early 2004, a team of scientists observing a harpy eagle nest noticed something odd. The nest had one baby in it that was about a month old when the scientists first observed it, and they noticed a crested eagle perched nearby. Every time the scientists visited the nest, the crested eagle seemed to be nearby, although the harpy eagle parents were also around and seemed just fine. The scientists observed the crested eagle adding branches to the nest and even bringing food to the harpy eagle baby. This continued for almost a year. The baby actively solicited food from the crested eagle and happily ate what it brought. At the same time, the harpy eagle parents allowed the crested eagle to approach, although generally the crested eagle didn’t come very close when the harpy eagle parents were around.

The scientists published a short paper about these observations in 2006, including a few hypotheses about the crested eagle’s behavior. They suggested that the crested eagle might have lost her own chick and transferred her maternal instincts to another eagle chick nearby, or she might have just been responding to the eagle chick’s requests for food. She might even have wanted to use that tree for her own nest, but when the bigger, stronger harpy eagles moved in, she abandoned her nest but hung around. A male crested eagle wasn’t observed, so it’s also possible she had lost her mate.

Sometimes different species of raptor do feed each other’s nestlings, although we don’t know why. It also occasionally happens with other types of birds, often male birds whose own nests are still being incubated by the female or by birds whose nest is very close to another nest with babies in it.

Another raptor that hunts animals that live in trees is the crane hawk, also from South America. It lives in forests that are near water and usually hunts by sitting in a tree and watching for potential prey. A lot of the time, though, it hunts like the New Guinea harpy eagle, climbing around in a tree and poking through any nooks and crannies to find animals that are hiding. In the case of the crane hawk, though, it actually has double-jointed legs that allow it to reach a foot into a little hole in a tree to grab prey. Most birds don’t have legs that are flexible enough to allow this behavior. The crane hawk eats a lot of nestling birds, bats, frogs, and other small animals that hide in tree cavities, including some larger invertebrates like cicadas and snails. The only other raptor known to both hunt like this and have double-jointed legs is a genus of African harrier-hawks that aren’t related to the crane hawk. Yes, it’s convergent evolution, at it again!

Let’s get out of the trees now and finish with another raptor Eva suggested. We talked about Ruppell’s griffon vulture in episode 159, but only very briefly.

Ruppell’s griffon vulture is a critically endangered vulture that lives in parts of central and eastern Africa. Unlike the raptors we’ve talked about so far in this episode, it spends a lot of its time soaring at high elevations, so it has really big wings. Its wingspan is as much as 8 and a half feet across, or 2.6 meters. It’s mostly brown and black and like other vultures, it doesn’t have feathers on its head, just a little bit of thin fluff. It will travel enormous distances to find the dead animals it eats, sometimes following herds of migrating animals to scavenge individuals that die of injury or illness. It doesn’t just eat the yummy soft parts of a carcass, it will also eat bones and even the hide of a dead animal. It has a long neck that helps it get to the best bits of its food, uh, from the inside of the carcass. It sometimes even climbs completely inside the rib cage of a dead animal to more easily get every scrap of food.

The way vultures eat is gross, which makes it fun for me to talk about, but vultures are incredibly important. They actually help stop the spread of diseases like rabies and anthrax by eating animals that died of the diseases. The vulture’s digestive tract is so effective that it kills off any viruses that caused the animals to die.

Ruppell’s vulture mates for life. It nests in cliffs, with hundreds of vulture pairs nesting very close together. The female lays one egg, and both parents take care of the baby when it hatches. Even after it can fly, the parents take care of their chick for almost a year while it learns how to find food on its own. Most vultures have relatively weak feet since they don’t use them to catch prey like other raptors, but Ruppell’s vulture has strong feet to help it perch on the cliffs where it nests.

Ruppell’s griffon vulture is one of the highest-flying birds known. It’s been recorded flying as high as 37,000 feet, or 11,300 meters, and we know it was flying at 37,000 feet because unfortunately it was sucked into a jet engine and killed. There’s so little oxygen at that height that a human would pass out pretty much instantly, but the vulture’s blood contains a variant type of hemoglobin that’s more efficient at carrying oxygen than ordinary hemoglobin.

As if all that weren’t enough for one bird, Ruppell’s vulture can also live to be 50 years old. That’s pretty good for an animal that mostly eats rotting and diseased meat.

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 263: Pair Bonds

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Thanks to Ella and Jack for this week’s topic suggestion, animals that mate for life or develop pair bonds! Happy Valentine’s Day!

Further reading:

Wisdom the albatross, now 70, hatches yet another chick

The prairie vole mates for life:

Swans mate for life:

The black vulture also mates for life:

The Laysan albatross:

Wisdom the Laysan albatross with her 2021 chick (pic from the link listed above). I hope I look that good at 70:

Dik-diks!

The dik-dik nose is somewhat prehensile:

The pileated gibbon (and other gibbons) forms pair bonds:

Show transcript:

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

Last February Ella and her son Jack suggested a Valentine’s Day topic. I already had the February episodes finished last year, but this year Valentine’s Day falls on a Monday and that just seems too perfect to pass up. So thanks to Ella and Jack, we’re going to learn about some animals that are monogamous.

Valentine’s Day falls on February 14th and in many European cultures is a day celebrating love and romance. It also falls at the very beginning of spring in the northern hemisphere, when many animals start finding mates.

Different species of animal have different relationships. Some animals are social, some are solitary. Every species is different because every species has slightly different requirements for reproducing due to different habitats, foods, how much care the babies need, and so forth.

There are different types of monogamy among animals and it can get complicated, just as it’s often complicated in people, so I’m going to simplify it for this episode into two categories: animals that mate for life and animals that form pair bonds. Animals that mate for life, meaning the male and female seek each other out every mating season to have babies together, don’t necessarily spend all their time together outside of mating season. Animals in pair bonds spend a lot of their time together, but they don’t always exclusively mate with each other. But some animals do both.

For instance, the prairie vole. This is a little rodent that lives in dry grasslands in central North America, in parts of the United States and Canada. It’s about the size of a mouse with a short tail although it’s more chonky than a mouse, like a small dark brown hamster. It spends most of its time either in a shallow burrow it digs among grass roots or out finding the plant material and insects it eats by traveling through aboveground tunnels it makes through densely packed plant stems. It lives in colonies and is a social animal most of the time, and the male in particular is devoted to his mate. He’s so devoted that once he’s found a mate, he will even drive away other females who approach him.

The only time the prairie vole isn’t social is during mating season, which is usually twice a year, in fall and in spring. At that time, mated pairs leave the colony and find a small territory to have their babies. The pair spends almost all their time together, grooming each other, finding and sharing food, and building a nest for the babies. When the babies are born, both parents help care for them.

The male prairie vole mates for life. Most of the time “mating for life” means that if one of a pair dies, the other will then find a new mate. But for the male prairie vole, if his mate dies, he stays single for the rest of his life. He also shows behaviors that are similar to grief in humans. The female prairie vole is a little more practical and although she also grieves if her mate dies, she’ll eventually find another mate. Researchers who study prairie voles have discovered that the hormones found in mated pairs are the same as those in humans who are in love.

That’s so sweet, and I wish I didn’t have to talk about the voles dying. I think the opposite of love isn’t hate; the opposite of love is grief. It’s okay to be sad even for a long time when someone you love dies or moves far away, or if your own pair bond doesn’t work out. It’s also okay to find happy moments even when you’re grieving. Life is complicated. Also, just going to point out, devoted as they are to each other, sometimes a prairie vole will mate with someone besides their own mate.

One bird that’s famous for being monogamous is the swan. It mates for life and also forms pair bonds. These pair bonds form while the swans are still young, and the young couples basically just hang out together long before they’re old enough to have babies. It’s no wonder pictures of swans appear on so many wedding invitations and Valentine’s day cards. It helps that they’re beautiful birds too. The black vulture also mates for life but no one puts vultures on a wedding invitation. Also, swans sometimes split up and find new mates. Things don’t always work out with a pair bond, even for swans.

Another large, beautiful bird that mates for life is the albatross, but it doesn’t form a pair bond. Most of the time the albatross is solitary, traveling thousands of miles a year as it soars above the open ocean, looking for squid, small fish, and other food near the surface of the water. But once a year in some species, and once every two years in other species, albatrosses return to their nesting grounds and seek out their mate.

Albatrosses live a very long time so are really picky about who they choose as a mate. Once a pair forms, they develop a complicated, elegant dance to perform together. Each couple’s dance is unique, which helps them find each other in a crowded nesting colony when they haven’t seen each other in a couple of years.

The oldest wild bird in the world that we know of is a Laysan albatross named Wisdom. She was tagged by scientists in 1956 when she was at least five years old already, and as of 2021 she was still healthy and producing healthy chicks with her mate. Her leg tag has had to be replaced six times because she’s outlasting the material used to make the tags.

The Laysan albatross is a smaller species of albatross, with a wingspan of not quite 7 feet, or over two meters. Its body is mostly white, although its back is gray, with black and gray wings and a dark smudge across the eyes that looks very dramatic. It spends most of the time in the northern Pacific between the west coast of North America and the east coast of Asia, but it only nests on 16 tiny islands. Most of these are part of the Hawaiian islands with a few near Japan, but recently new breeding colonies have been spotted on islands off the coast of Mexico.

Wisdom the albatross is estimated to be at least 70 years old as of 2021 and she’s raised 30 to 36 chicks successfully. Because of her age, which is old even for an albatross, she may have outlived her first mate and taken another. She’s been with her current mate since at least 2012.

Albatrosses only lay one egg during nesting season. Both parents help incubate the egg and feed the baby when it hatches. It takes two or three months for the egg to hatch, depending on the species. Once the egg hatches, it’s at least another 5 or 6 months before the chick is old enough to leave the nest and care for itself, and in some species this is as much as 9 months. This means a big time and energy investment for both parents.

Albatrosses don’t reach sexual maturity until they’re at least five years old. Birds younger than this still join the breeding colony and practice their dance moves for when they’re old enough to choose a mate.

Pair bonding and mating for life are common in birds, rare in amphibians, reptiles, and fish, and surprisingly rare in mammals. One mammal that both mates for life and forms a pair bond is a tiny antelope called a dik-dik.

The dik-dik lives in parts of eastern and southern Africa and is barely bigger than a rabbit, which it somewhat resembles in shape. It stands less than 16 inches tall at the shoulder, or 40 cm, although its back and rump are arched and rounded and so are actually higher than the shoulder. Females are usually larger than males, while only males have horns. The horns arch back from the head but because the male has a tuft of long hair on the top of his head, and because the horns are only about 3 inches long at most, or 7.5 cm, they can be hard to see.

The dik-dik has an elongated snout that’s somewhat prehensile. It lives in hot areas without much water, so it gets most of its moisture from the plants it eats. Most of the time hot weather doesn’t bother it, but on exceptionally hot days it can cool down by panting through its long nose. Its nose is lined with blood vessels close to the surface and it has special nose muscles that allow it to pant quickly. Air moving over the blood vessels helps cool the blood.

Because pretty much everything eats the dik-dik, traveling long distances to find a mate is dangerous. Once the dik-dik finds a mate, they stay together for life in a small territory and spend most of their time together. Females give birth to one fawn twice a year, and the fawn no longer needs its parents at about 7 months old. Parents drive away their grown offspring, who leave to find a mate and territory of their own.

Humans, of course, strongly pair bond because we’re such intensely social creatures, and many people choose a partner and stay with them for life. Then again, we don’t always. Surprisingly, our closest living cousins, the great apes, are also very social, but they don’t typically form pair bonds and females may mate with different males.

The gibbon, which is a lesser ape instead of a great ape, does often form long-lasting pair bonds. We’ve talked about various species of gibbon in previous episodes. Gibbons are the apes that sing elaborate duets with their mates, with their children sometimes joining in as a chorus.

Here’s a pair of pileated gibbons singing together. The female is named Molly and was in a rehabilitation center after being injured, but she found a wild mate while she was recovering:

[gibbons singing]

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 127: New World Vultures

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This week we’ll learn about some vultures from North and South America–some living, some extinct, and one mystery! Thanks to Maureen and Grady for their suggestions!

Thanks also to Kat White for the Turkey Vulture Song that opens the podcast! If you’d like to buy her album “In the Eye of the Owl,” visit her website at katwhitemusic.com/

Further listening:

CritterCast episode 35 Turkey Vultures

How to tell a turkey vulture apart from a black vulture:

The king vulture has a very bright head:

The Andean condor soaring:

The painted vulture:

Show transcript:

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

Way back in episode 40 we learned about the bearded vulture and some of its close relatives. This was a suggestion from Maureen, and I always meant to revisit vultures so we could learn about more vulture species. Then Grady wanted to know how long buzzards stay in the sky until they come down for food, and why do they soar for so long? That’s a great question that shows some good observation skills, so let’s go back to vultures and learn more about them.

Those of you listening in Europe may be wondering why I’m talking about buzzards in a vulture episode. That’s because we’re going to learn about new world vultures today, and in North America the general term for a vulture is a buzzard. In Europe, a buzzard is actually a type of eagle.

Before we get into the episode, though, I should mention that the intro music we heard is by Kat White, who was kind enough to let me use a snippet. It’s from the album “In the Eye of the Owl,” which is all about animals and so much fun I wanted to let everyone know about it. I’ll put a link in the show notes so you can find out more about the songs.

Kat also let me know about a turkey vulture named Lord Richard who lives in a park called Lindsay Wildlife Experience in California. Lord Richard just turned 45 years old and got a huge birthday party! So as you can see, vultures can live a long time in captivity, although usually not as long in the wild. Then again, the oldest verified vulture is an Andean condor born in captivity in 1930 who died in 2010 at the age of 79. Andean condors in the wild can live more than 50 years. This makes Lord Richard sound like a positive youngster.

New World vultures are native to the Americas and all of them are pretty big. In fact, condors are vultures and they’re extremely large birds. The New World vultures aren’t very closely related to each other but they all share some traits.

Vultures are scavengers that find dead animals to eat. The meat from dead animal carcasses is referred to as carrion. Vultures will also eat rotting fruit and garbage sometimes. Because they eat meat that is often spoiled, vultures have an extremely acidic digestive system that helps the bird digest its food quickly and kills off any bacteria that might make it sick. It also has beneficial bacteria in its digestive system that neutralize toxins.

But that’s not where the adaptations to eating carrion end. The vulture is a highly specialized bird. Most vultures don’t have many feathers on their heads, unlike other birds. If you’re snacking right now, you might want to pause this until you’re done. Quite often a vulture will actually stick its head into a rotting animal carcass to get at the, uh, softer parts. This means its head gets covered in rotting gunk and a lot of bacteria. If it had head feathers, they would be destroyed by bacteria.

One interesting thing about vultures of all kinds is that they actually help stop the spread of diseases like rabies and anthrax. Their digestive tract is so effective that it kills off viruses that caused the animal to die, so it’s actually beneficial to the environment in general and to farmers. Unfortunately, farmers don’t always know this and think vultures spread disease. Many vultures are protected species in most countries to stop farmers and other people from shooting them.

Quite often you’ll see a vulture perched somewhere up high with its wings spread. It does this to dry them when it’s been rainy or foggy, but also so that sunlight will help kill off any bacteria on the feathers. That’s another reason the vulture has no feathers on the head, so that sunlight can kill off any bacteria on its skin.

Vultures do some other gross stuff, like pee on their own legs. They do this to cool down in hot weather, since as the liquid droppings evaporate it cools the legs, and therefore cools the blood flowing through the legs, and therefore cools the vulture’s body temperature overall. But vultures also like to bathe in shallow water, which helps clean the skin and the feathers, and which of course washes any droppings off their legs.

Vultures also puke up what they’ve eaten if they feel threatened. This serves two purposes. The vulture is immediately much lighter and can fly away more easily, and the horrible stench of partially digested rotting meat may drive away a potential predator.

There are seven species of new world vulture alive today. The most common one is the turkey vulture, which lives throughout most of North and South America. The next most common is the American black vulture, which lives in South America up to the southern parts of North America. From a distance it can be hard to tell the two apart, but the black vulture has silvery tips on its wings.

The turkey vulture is the vulture most often referred to as a buzzard. It has a wingspan of about six feet, or over 1.8 meters, although it doesn’t weigh more than about five pounds at most, or 2.4 kg. It’s kind of a picky eater, surprisingly, and doesn’t like really rotten meat. It often hangs out with black vultures, but black vultures are more aggressive even though they’re a little smaller, and the turkey vulture will wait until the black vultures are done eating before it moves in to finish off what’s left.

Black vultures and turkey vultures aren’t very closely related and don’t really look very similar if you see them up close. The turkey vulture has a red head that looks a lot like a male turkey’s, which is where it gets its name. The black vulture has a gray head.

Unlike the turkey vulture, which almost exclusively eats carrion and rotting fruit and sometimes vegetables, the black vulture will also eat eggs and sometimes kills small animals, especially baby animals. It hunts in groups and can even kill newborn calves.

If you want to learn more about the turkey vulture, the Critter Cast Podcast has a really good episode all about it. I’ll put a link in the show notes in case you don’t already listen to Critter Cast.

The other new world vultures are mostly restricted to South America, except for the California condor. We’ll talk about condors in a minute. The king vulture is most common in South America although it also lives in parts of southern Mexico and in Central America. Unlike most vultures, which are mostly black, its feathers are mostly white with some gray and black markings. The skin of its bald head is brightly colored, with different individuals having different coloration—red, orange, yellow, purple, even blue, with an orange crest on its bill in adult birds. It also has a white eye with a red rim, and short bristles on the head. The ancient Maya people considered the king vulture a messenger of the gods, which is pretty neat.

The king vulture is big even for a vulture, with a wingspan of up to about 7 feet, or 2 meters, which makes sense since it’s most closely related to the Andean condor. It has a stronger bill than most vultures, which helps it tear open an animal carcass that other vulture species might not be able to access. Often, other vulture species will wait until a king vulture has opened a carcass and eaten its fill before they move in and eat too. It especially likes the skin and tougher meat of a carcass, and its tongue is raspy to help it pull meat off bones.

The king vulture’s ancestors lived farther north, into parts of North America, but went extinct around 2 ½ million years ago. We don’t really know all that much about the ancestors of the New World vultures, though, because they’re not very common in the fossil record. But the New World vultures are related to the terratorns, huge birds that are extinct now. We’ve discussed terratorns once before way back in episode 17, about the Thunderbird, but let’s discuss them again because they were incredible birds.

We have a decent number of terratorn remains from the La Brea Tar Pits and a few other places. The terratorns were bigger even than condors. A number of species lived throughout the Americas, with even the smaller species having an estimated wingspan of around 12 feet, or 3.8 meters. 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 16 feet, or 6.5 meters, and possibly as much as 26 feet, or 8 meters. That’s the size of a small aircraft.

Researchers think Argentavis was an efficient glider, hardly needing to flap its wings. But it wasn’t very maneuverable, so researchers also think it was probably a scavenger like modern vultures. Smaller terratorns may have been active hunters, more like eagles than vultures. Argentavis had strong legs and probably took off by running into the wind with its massive wings spread, sort of like an airplane taking off, so it didn’t have to flap its wings at all.

That brings us to Grady’s question about why and how buzzards soar for so long. Argentavis would have spent most of its time soaring, hardly ever needing to flap its wings. Its wings weren’t even very strong, and it might not even have been able to flap them when they were extended. The turkey vulture, or buzzard, is especially good at soaring for long periods of time, sometimes for hours, without needing to flap its wings.

If you’ve noticed, soaring birds like vultures, eagles, and hawks tend to fly in circles. There’s a reason for this. When the wind blows over a hill or mountain, it creates an updraft, a breeze that blows directly upward. Similarly, air rises from land that’s been warmed by the sun, causing columns of warm air called thermals. A soaring bird stays in these updrafts and thermals by flying in circles. Vultures also have wingtips where the feathers are spread out, so that each flight feather is separated from the next by a small space. Each of these feathers acts like a tiny wing of its own, which helps keep the vulture gliding forward and not downward. All this wind over the wingtip feathers causes a lot of pressure, though, and vultures have a special bone at the wingtip that helps strengthen and support the flight feathers. Soaring instead of flapping conserves a lot of energy, which is why vultures will soar for as long as they can, looking for food.

Most New World vultures have a good sense of smell, which is unusual for birds. The turkey vulture finds a lot of its food by smell. The black vulture doesn’t have nearly as good a sense of smell, though, and as a result it often follows turkey vultures to find carcasses, then bullies the turkey vultures out of the way to eat first. That’s not very nice, birds. In addition, the turkey vulture has keen eyesight, which helps it find dead animals that might not have started to smell yet.

So let’s talk about those condors now. There are two species of condor alive today, the California and the Andean. We covered the California condor in episode 44, extinct and back from the brink. The California condor actually went extinct in the wild in 1987, with only 22 birds alive in captivity, but an ongoing captive breeding program saved it from extinction and captive-bred birds started to be released into the wild in 1991. But there are still fewer than 500 individuals alive today, so it’s still in danger of extinction. The California condor only lives in a few small areas of western North America today, but around 40,000 years ago it lived throughout North America. Part of the reason it’s still so rare is that it reproduces very slowly. A pair doesn’t nest every year, and even when they do, the female only lays one egg. A young condor depends on its parents for a full year, both for food and to learn how to fly. It can take a young condor months to learn how to fly properly, and researchers sometimes observe awkward crash landings that are probably pretty funny, although maybe not so funny to the condor.

The California condor’s wingspan can be up to almost ten feet, or 3 meters. This is huge, but the Andean condor is even bigger. Its wingspan is nearly eleven feet, or 3.3 meters. The Andean condor lives in and near the Andes Mountains along the western coast of South America. It’s mostly black with silvery patches on the wings and a white ruff around the neck, and its head is gray in color but can flush reddish to communicate with other condors. The male also has a comb on the top of its head.

The Andean condor’s feet are adapted for walking, not fighting. Its feet aren’t very strong and its talons aren’t very sharp. It does sometimes kill small animals like rabbits, but its feet are so weak that it can’t use them to attack. Instead, it stabs the animal to death with its beak.

Like Argentavis, the Andean condor’s wings are built for soaring, not flapping. It can soar for hours without needing to flap its wings once, sometimes traveling hundreds of miles in a day to find food.

It’s a social bird that mates for life, and one of its courtship rituals is a hopping, flapping dance. Keep in mind that this is a bird with wings over five feet long. That would be a pretty impressive dance. The Andean condor nests high in the Andes Mountains on cliffs that predators can’t reach and lays one or two eggs.

Let’s go back to the king vulture now to finish up, because there’s a mystery associated with the king vulture. In the 1770s, a man named William Bartram traveled through Florida and took notes about the animals and plants he saw. He published a book of his travels in 1791 and in it, he included information about a bird he called a painted vulture. He said it was fairly common in Florida and that he’d even shot one himself. The description he gave sounds like a king vulture except that Bartram described its tail as white with a black tip, not entirely black.

But remember, the king vulture primarily lives in South America. It is known in the very southern parts of North America in Mexico, but not Florida. What’s going on?

Some people think Bartram included the painted vulture as a hoax. Some people think he got it mixed up with a different bird, the Northern caracara, a bird of prey which only looks slightly like a king vulture. Some people think there may have been a small population of king vultures in Florida at the time that later went extinct, possibly a subspecies of king vulture with a mostly white tail instead of all black.

Bartram wasn’t the only person who reported seeing the painted vulture. In 1734 an English naturalist and artist, Eleazar Albin, painted a vulture that looked almost identical to the one Bartram described 30-odd years later, tail and all. It’s not completely clear where Albin saw his bird, but as far as researchers can determine Bartram wasn’t aware of the painting. So it’s possible that a subspecies of king vulture once lived in Florida but went extinct soon after Bartram saw it. If he and Albin hadn’t documented it, no one alive today would have any idea the painted vulture ever existed.

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

Thanks for listening!

Episode 040: Bone-eating vultures

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This week we look at a couple of unusual vultures, the bearded vulture and the Egyptian vulture. Thanks to Maureen J. who recommended this week’s topic!

The bearded vulture, badass bird:

This bearded vulture is probably thinking about eating bones right now:

The Egyptian vulture cares about its appearance:

Show transcript:

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

Halloween is over, we’re all pretty sick of candy, and it’s time to move on to something besides monsters. Something that is not associated with Halloween candy in any way, preferably. I ate, like, three bags of gummy spiders by myself this year.

Special thanks to Maureen J. who recently made several topic recommendations. One of her suggestions in particular is taking me down various research rabbit holes, which is a lot of fun but means it’ll be a while before that episode is ready. So in the meantime let’s learn about one of her other suggested topics, vultures.

Vultures are divided into two big groups, old world and new world vultures. The two groups are related, but not closely. Today we’re only looking two old world vultures, and in fact, let’s start with a bird that’s considered an old world vulture but is actually not any more closely related to them than the new world vultures are. That’s the bearded vulture.

The bearded vulture lives in the high mountains in parts of Asia, Africa, and southern and eastern Europe, and like other vultures it spends a lot of its time waiting for animals to die or just looking for already-dead animals that it can eat. Unlike most other vultures it often gets impatient and cuts out the waiting part by hunting small animals. It especially likes tortoises. Like golden eagles, the bearded vulture will scoop up a tortoise, carry it way way up high, and drop it. Then it coasts down and eats the smashed tortoise. There are stories that the bearded vulture will also sometimes attack larger prey with its wings, driving the animal over a cliff where it plunges to its death. This is a hardcore bird.

To add to the general air of all bearded vultures secretly being members of Norwegian death metal bands, they also wear corpse makeup. I don’t mean the bird’s ordinary coloring, although it is pretty impressive. Unlike other vultures, it doesn’t have a bald head. Adult birds have white heads with a black band from the eye to the base of the bill that continues in a sort of mustache hanging from either side of the bill. The rest of the bird is dark gray, brown, and cream-colored. No, I mean the bearded vulture actually rubs soil and dust containing ferrous oxide on its body to stain the feathers a rusty red, apparently because it just likes the way it looks. In fact, researchers think the color is a status symbol. A bird that has the time and energy to spend hours preening red dirt into its feathers is a bird that has its life nicely sorted. It also indicates to other bearded vultures that the bird has a big territory and knows it well, since the dust bathing is done in secret.

But let’s face it, the most metal thing about this bird is what it eats. The rotting flesh of dead animals? Pfft, that’s for other scavengers. Most of the time the bearded vulture doesn’t pay any attention to meat. It just wants the bones.

The bearded vulture’s stomach is specialized to digest even large bones in about 24 hours. Bone marrow has a high nutritional content, higher even than muscle tissue, but most animals find it difficult to get to the marrow easily enough to extract the nutrients without more effort than it’s worth. The bearded vulture just picks a bone and either swallows it whole, or, if the bone is too big to swallow, either drops it from a height the same way it does with tortoises or batters it against a rock with its bill until it shatters. But it can swallow bones up to 11 inches long, or 28 cm.

Most vultures regurgitate partially digested food for their babies. The bearded vulture naturally doesn’t do anything that soft. Instead, the parent vultures carry bones back to the nest and the babies swallow them. Young birds don’t leave the nest until they’re three or four months old, and they may continue to rely on their parents for food and help for up to two years.

The bearded vulture is a big bird with long, strong legs. Its wingspan can be over nine feet wide, or 2.8 meters, and the bird may weigh over 17 pounds, or 7.5 kilograms. It can carry bones and tortoises that weigh almost as much as it does.

The bearded vulture is also called the lammergeier, which is German for lamb-hawk. In many ways it’s more like a hawk than a vulture, and in fact falconers have sometimes kept them as tame birds. In the past, unfortunately people thought the bearded vulture killed children and lambs, which is why they’re mostly extinct in Europe—they were all killed.

The bearded vulture is most closely related to the Egyptian vulture, which also happens to be one of the smallest vultures in the world. It’s still a pretty big bird, though, with a wingspan up to about 5 ½ feet, or 170 cm.

The Egyptian vulture is white with black flight feathers, but like the bearded vulture, it will rub its feathers with rust-colored dirt to stain them red. While it has a floof of longer feathers on the back of its head and neck that’s called a hackle, its face is bare of feathers and is also a surprisingly bright shade of yellow or orange. The tip of the hooked beak is black. Both the Egyptian vulture and the bearded vulture have wedge-shaped tails, unlike all other vultures.

The Egyptian vulture doesn’t just live around Egypt. There are three subspecies that live in parts of Africa, Asia, and southwestern Europe. It prefers lower mountains and hills, and some populations migrate while others live in the same area year round. Overall, Egyptian vultures are endangered, and while they’re protected, they do tend to get electrocuted on power lines. This is also a problem for other big birds that live around people, like eagles.

Egyptian vultures eat carrion, not bones, but they also eat insects, fish, rotting fruit, and occasionally kill small mammals and reptiles. They also really like eating the eggs of other birds, but if an egg is too big for the vulture to swallow, it will pick up rocks and throw them at the egg until it breaks. That’s not the only tool use Egyptian vultures show. They like to gather wool to line their nests, and sometimes a vulture will pick up a stick in its bill and collect wool on the stick to more easily transport. That’s pretty sophisticated in the bird world.

Egyptian vultures also eat dung, especially from cows. Researchers think they do this for carotenoid pigments present in the dung, which helps keep the vulture’s face bright yellow or orange. Who knew vultures were so particular about their appearance?

Because the Egyptian vulture is smaller than other vultures, it often has to wait its turn at the carcasses it scavenges. Its slender bill is ideal for reaching smaller pieces of meat that other vultures have overlooked.

Bearded vultures are solitary except for mated pairs, but Egyptian vultures are more social. Sometimes Egyptian vultures will build their nests near other vulture nests on cliffs and in big trees. In those cases, babies will climb into each others’ nests to get more food.

One subspecies of Egyptian vulture lives in the Canary Islands and are bigger and heavier than the other subspecies. The Canary Islands were first colonized around 2,500 years ago. Genetic research shows that the Canary Islands vultures arrived at about the same time as the human settlers and their cattle. This is a rare but happy example of the arrival of humans actually helping a species thrive instead of driving them to extinction. Unfortunately these days the Canary Islands vultures are rare. Only about 25 breeding pairs remain.

One interesting thing about both Egyptian and bearded vultures. They mate for life, but sometimes a pair will accept a second male into their little family. Both males will mate with the female and help raise the babies. This increases the likelihood that the chicks will survive to adulthood.

Life is tough out there in the wild. Babies can use all the help they can get. Even if they are bone-eating death bird babies.

You can find Strange Animals Podcast online at strangeanimalspodcast.com. We’re on Twitter at strangebeasties and have a facebook page at facebook.com/strangeanimalspodcast. If you have questions, comments, or suggestions for future episodes, email us at strangeanimalspodcast@gmail.com. If you like the podcast and want to help us out, leave us a rating and review on iTunes or whatever platform you listen on. We also have a Patreon if you’d like to support us that way. Rewards include stickers and twice-monthly bonus episodes.

Thanks for listening!