Episode 381: Out of Place Birds

Thanks to Richard from NC, Pranav, and Alexandra for their suggestions this week!

Further reading:

ABA Rare Bird Alert

One Reason Migrating Birds Get Lost Is Out of This World

Inside the Amazing Cross-Continent Saga of the Steller’s Sea-Eagle

A Vagrant European Robin Is Drawing Huge Crowds in China

Bird migration: When vagrants become pioneers

A red-cockaded woodpecker:

Steller’s Sea Eagle making a couple of bald eagles look small:

Steller’s sea eagle:

A whole lot of birders showed up to see a European robin that showed up in the Beijing Zoo [photo from the fourth article linked above]:

A robin:

Mandarin ducks:

Richard’s pipit [photo by JJ Harrison (https://www.jjharrison.com.au/) – Own work, CC BY 3.0, https://commons.wikimedia.org/w/index.php?curid=23214345]:

Show transcript:

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

We’re talking about some birds again this week, with a slightly mysterious twist. These are birds that have shown up in places where they shouldn’t be, sometimes way way far from home! Thanks to Richard from NC for inspiring this episode and suggesting one of the birds we’re going to talk about, and thanks to Pranav for suggesting we cover more out of place animals.

Last week we talked about some woodpeckers, and I said I thought there was another listener who had suggested the topic. Well, that was Alexandra! Let’s start today’s episode talking about the red-cockaded woodpecker, another bird Alexandra suggested.

The red-cockaded woodpecker is native to the coastal southeastern United States, where it lives in pine forests. It’s increasingly threatened by habitat loss since the pine forests get smaller every year, and not only does it need old-growth pine forests to survive, it also needs some of the trees to be affected by red heart fungus. The fungus softens the interior wood, which is otherwise very hard, and allows a woodpecker to excavate nesting holes in various trees that can be quite large. The female lays her eggs in the best nesting hole and she and her mate raise the babies together, helped by any of their children from previous nests who don’t have a mate of their own yet. When they don’t have babies, during the day the birds forage together, but at night they each hide in their own little nesting hole to sleep.

It’s a small bird that doesn’t migrate, which is why Beth Miller, a birder in Muskegon, Michigan, couldn’t identify it when she spotted it on July 1, 2022 in some pine trees near a golf course. She took lots of photos and a recording of its calls, which she posted in a birding group to ask for help. She knew the bird had to be a rare visitor of some kind, but when it was identified as a red-cockaded woodpecker, she and nine birder friends went back to the golf course to look for it. Unfortunately, they couldn’t find the bird again. It was the first time a red-cockaded woodpecker had ever been identified in Michigan, although individual birds do sometimes wander widely.

While bird migration isn’t fully understood, many birds use the earth’s magnetic field to find their way to new territories and back again later in the year. Humans can’t sense magnetic fields but birds can, and being able to sense Earth’s magnetic field helps birds navigate even at night or during weather that keeps them from being able to see landmarks.

But sometimes birds get lost, especially young birds who have never migrated before or a bird that gets caught in storm winds that blow it far off course. If a bird shows up somewhere far outside of its normal range, birdwatchers refer to it as a vagrant, and some birders will travel great distances to see vagrant birds.

One interesting note is that birds navigating by the earth’s magnetic field can get confused if the magnetic field is disrupted by geomagnetic storms, including solar flares, sunspots, and coronal mass ejections. Very recently as this episode goes live, the aurora has been occasionally visible across much of the world. The aurora is caused by charged particles from the sun reaching Earth’s atmosphere, causing a colorful glow or shimmer in the night sky, and it’s usually only visible at or near the poles. This month it was visible in places far away from the poles. Fortunately, a really strong geomagnetic storm like the ones this month can actually make it easier for birds to migrate. Instead of getting a scrambled sense of the earth’s magnetic field, a strong geomagnetic storm can temporarily knock out a bird’s ability to sense the magnetic field at all, and that means it uses landmarks, the position of the stars and sun, and other methods to find its way.

Sometimes a bird just flies the wrong way, like the Steller’s sea eagle that showed up in Alaska at the end of August 2020. Steller’s sea eagle is native to the coast of northeastern Asia and is increasingly threatened due to habitat loss, pollution, climate change, poaching, and overfishing, a real problem if you’re an eagle that eats a whole lot of fish. Only about 4,000 of the birds remain in the wild. It’s a huge eagle, one of the biggest in the world, with a big female having a wingspan over 8 feet across, or almost 2.5 meters. Some unverified reports indicate birds with a wingspan over 9 feet across, or 2.8 meters. It has a huge yellow bill and feet, and is black and white in color. It’s related to the bald eagle but is larger and heavier, and its head is black instead of white.

To an eagle as big as Steller’s sea eagle, the distance between the eastern coast of Russia and the western coast of Alaska is very small, so it’s not all that unusual for birders to see one in Alaska. The difference in 2020 is that the bird was far inland, not on the coast. Then, several months later, a Steller’s sea eagle was reported in Texas. Texas! Very far away from Alaska and the northeastern Asian coast.

No one could definitively say if the Texas bird was the same one seen in Alaska, but a few weeks before there had been a massive storm that could have blown the eagle to San Antonio. It was the first time a wild Steller’s sea eagle had been spotted in Texas.

But the bird wasn’t done traveling. In late June 2021, a ranger in eastern Canada spotted the sea eagle. It was seen by multiple birders and photographers, some of whom got pictures good enough to compare to the Alaska photos from the year before, and it was the same bird! A few months later it was spotted in Nova Scotia, Canada, and in mid-December 2021 it arrived in southern Massachusetts in the United States for a few days. By the end of 2021 it was in Maine.

Since then the eagle appears to divide its time between Maine in the northeastern United States and Newfoundland, Canada, not too far away.

Richard from NC suggested that sightings of Steller’s sea eagle might explain the mystery of Washington’s eagle. I go into detail about Washington’s eagle in the Beyond Bigfoot & Nessie book. There is a rare color morph of Steller’s sea eagle that is almost all black, which matches Audubon’s painting of Washington’s eagle, but Steller’s sea eagle always has a yellow bill, not a dark one as Audubon painted. Still, it’s a very interesting theory that matches a lot better than the theory that Washington’s eagle is just a big juvenile bald eagle.

Eagles are spectacular birds, but even an ordinary bird turns into a celebrity when it shows up somewhere far outside of its normal range. That’s what happened to a European robin at the beginning of 2019. We talked about the European robin back in episode 333. It’s a common bird throughout much of Europe and parts of Asia, but it’s only been documented in Beijing, China three times. The third time was when one showed up in the Beijing Zoo in 2019, at least 1,500 miles, or 2,400 km, away from its usual range. Birdwatching is an increasingly popular hobby in China, and hundreds of birders showed up at the zoo not to see the animals it has on display but to see a little robin that someone in England would barely glance at.

A few months before that, on the other side of the planet, a Mandarin duck showed up in Central Park in New York City. Birders showed up soon after to look at it. The Mandarin duck is a beautiful bird related to the wood duck native to North America, but it’s native to China and other parts of east Asia. The male has a red bill, rusty red face with white markings, and purplish feathers on his sides, while the female is softer and more muted in color. Both males and females have a purplish crest and the male also has a reddish crest on both of his wings that sticks up like a sail when his wings are folded.

In other words, the male in particular is a spectacular duck, and the duck that showed up at Central Park was a male in full breeding plumage, looking his best. Since Mandarin ducks are so attractive and increasingly threatened in the wild, many zoos and private owners keep them, and the Central Park duck did have a band on his leg that indicates he might have been an escaped bird. But no one ever claimed him and in March of 2019 he flew off for good.

Vagrant birds show up in weird places all the time, especially in spring and fall when most migratory birds are on the move. Sometimes a vagrant bird returns to the mistaken area in following years, brings its mate and offspring, and essentially founds a new migratory route. This is what scientists think has happened with several species of songbird that breed in Siberia and migrate to southeast Asia for the winter.

Richard’s pipit is a medium-sized songbird with long legs, a long tail, and a relatively long bill. It’s mainly brown and black, with lighter underparts. It looks like a stretched-out sparrow. It migrates to southern Siberia, Mongolia, and a few other parts of central Asia to nest during the summer, and flies back to India and other parts of southeast Asia to spend the winter. But a small population flies west instead of south and spends the winter in Spain, Italy, and surrounding areas instead of in India.

For a long time scientists thought the birds seen in Europe were just lost. They’re still quite rare in Europe compared to their high population in Asia. Then a team of scientists caught 81 of the birds, installed leg-bands on all of them and GPS loggers on seven of them, and released them again. The birds migrated north to breed, then returned to Europe instead of Asia to spend the winter, where some were caught again and their leg-bands recorded. So just remember that when a bird shows up where it’s not expected, it might not be as lost as people think.

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

Thanks for listening!

Episode 326: The Harpy Eagle and Friends

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 277: Rewilding Scotland

This week is Caitie Sith and Dave’s episode! They want to learn about animals reintroduced to Scotland, especially the Highland wildcat!

The Scottish (or Highland) wildcat:

The Eurasian lynx:

The Eurasian beaver (with babies!):

The white-tailed eagle:

Reindeer in Scotland:

The pine marten:

Show transcript:

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

This week is Caitie Sith and Dave’s episode, where we’ll learn about the re-wilding of Scotland! Re-wilding is the process of restoring an ecosystem to its natural state, basically reversing habitat loss. Most of the time there’s a lot more to it than just reintroducing native animals, but sometimes that’s all that’s required.

Scotland is a part of the island of Great Britain, north of England. People have lived there since the last glaciers melted at the end of the Pleistocene, around 12,000 years ago. During the Pleistocene and a few thousand years after the glaciers melted, Scotland was connected to Europe by a lot of marshy land where today there’s ocean, and naturally many animals lived in Scotland that were also found in Europe at the time. Some of the ice age megafauna that lived in Scotland included the woolly rhinoceros, woolly mammoth, bison, aurochs, wild boar, saiga antelope, giant deer, red deer, reindeer, moose, wild horse, beaver, walrus, Polar bear, brown bear, lynx, wolf, Arctic fox, and cave lion. Many fossil and subfossil remains of Pleistocene animals were destroyed by the formation and movement of thick glacier ice, which scoured the land down to bedrock in many places, so those are only the animals we know for sure lived in Scotland.

But Scotland wasn’t covered by glaciers all the time. The Pleistocene wasn’t a single ice age but a series of cold events interspersed with warming trends. During these interglacial periods, which lasted some 10- to 15,000 years at a time, animals would move to Scotland from other places or become more numerous than before. Then the climate would start cooling again, glaciers would slowly form over many years, and animals would move to areas where there was more food. This happened repeatedly over a period of more than 2.5 million years.

In other words, while we have some fossils of Pleistocene animals that once lived in Scotland, we don’t have nearly as many as have been found in England, Ireland, and Wales. But what we do know is that Scotland was once teeming with all kinds of animals we’d never associate with the country today, like cave lions and Polar bears!

Much of the ice age megafauna went extinct around 12,000 years ago when the last glaciers melted and the climate started warming. Cold-adapted animals couldn’t always survive in a warmer climate, not to mention that as the climate changed, the types of plants available to eat changed too. Some animals migrated away or went extinct, while some were able to stay in Scotland successfully. This included the red deer, reindeer, wild boar, walrus, brown bear, and lynx.

If you’re wondering why that list is full of animals that don’t actually live in Scotland these days, like the brown bear and lynx, it’s because humans hunted many of the native Scottish animals to extinction. Others went extinct due to habitat loss or competition with introduced animals. Many surviving species are endangered today for the same reasons.

For example, the Scottish wildcat, also called the Highland wildcat. We talked about it briefly in episode 52 way back in early 2018. One of the animals that migrated to Scotland after the Pleistocene, but before sea levels rose and cut the British Isles off from Europe, was the European wildcat. The Scottish population has been separated from the European population for at least 7,000 years, and some researchers think it should be classified as a subspecies of European wildcat.

The Scottish wildcat is a little larger than a domestic cat and is always tabby striped. It has a bushy tail with a black tip, a striped face and legs, never any white markings, and is usually dark in color with black paws. It’s a solitary animal that mostly lives in woodlands, where it eats mice, voles, and other rodents, rabbits, and birds. It used to be common throughout much of the British Isles, but these days it’s only found in parts of Scotland.

You’d think people would be excited to have a genuine wildcat living in their country, since wildcats are pretty awesome and eat animals that can damage crops. But for some reason, until recently people thought these wildcats were pests and would shoot them on sight. Some people thought the wildcats were killing game birds, which is rare, or that they were dangerous, which isn’t true. At the same time, the people shooting wildcats were letting their domestic cats roam freely, which has caused an even bigger problem to wildcats than getting shot at.

Like other wildcat species, the Scottish wildcat can and will cross-breed with domestic cats. The resulting kittens are fertile, meaning they can have babies with either wildcats or domestic cats. Kittens are great, of course, but domestic cats are a different species from wildcats. Hybrid cats are less suited to live in the wild, but too wild to be good pets, and if too many domestic cats breed with wildcats, soon there won’t be any real wildcats left. Not only that, domestic cats carry diseases that wildcats can catch.

The Scottish wildcat is a protected species these days, with conservation efforts in place to keep the wildcats and their habitat as safe as possible. One important step is to encourage people to get their domestic cats neutered. This is healthier for pet cats anyway and will help keep tomcats from spraying and fighting, and of course it stops them from having kittens with wildcats.

Another felid that once lived in Scotland is the Eurasian lynx. It still lives in parts of Asia and Europe, but it went extinct in Scotland several hundred years ago, mainly due to deforestation and hunting for its fur. It’s about 28 inches tall at the shoulder, or 70 cm, and is a heavily built animal with thick spotted fur and a short bobtail. The tip of its tail is black although the rest of the animal is mostly tan or brown with darker brown spots, and it has long black tufts of fur on the tips of its ears. It’s slightly bigger than the related Canadian lynx.

Conservationists have wanted to reintroduce the Eurasian lynx to Scotland for years. Since the lynx is threatened in the rest of its range by habitat loss and hunting, reintroducing it to its former range in Scotland would help it and the ecosystem in general. With no large predators to keep their numbers in check, the population of roe deer in Scotland is too high to be healthy, and the lynx loves to eat roe deer.

Some people worry that if the lynx is reintroduced to Scotland, it will be dangerous to humans and livestock. But the lynx is a shy, solitary animal that avoids humans as much as possible. There are enough roe deer alone to sustain a population of over 400 lynxes in the wilder parts of Scotland, especially in the Highlands. The lynx also spends almost all of its time in forests and doesn’t like open pastures. It’s been successfully reintroduced to its former range in other countries, with a nice side effect being increased tourism to national parks where it’s now found.

Scotland also used to have beavers, which were hunted to extinction in the 16th or 17th century. Then, in 2009, the Eurasian beaver was reintroduced to parts of Scotland and is doing great! There are more than 1,000 beavers living in Scotland now. Beavers are considered a keystone species, a term we haven’t really examined on the podcast before, but it means that an animal is so important to an ecosystem that if it goes extinct in an area, the ecosystem sort of falls apart and many other animals go locally extinct soon after.

Beaver ponds create a winter habitat for many types of fish, and beaver dams don’t stop fish like salmon that migrate upriver to spawn. The dams help reduce flooding, improve water quality, and create cover for lots of fish and other animals.

Naturally, though, some people complain about the beavers, because there will always be someone who complains about anything. Some people think beavers eat fish and will eat up all the fish that humans want to catch. Beavers actually don’t eat fish at all, they only eat plant material. Some people think beavers carry the giardia parasite, which causes a bacterial infection sometimes called beaver fever that’s spread in water, but giardia is actually mostly spread by domestic dogs. Some people complain that beavers fell trees and build ponds, and both these things are true. But the beaver is just doing what it’s supposed to do, and as we just learned, this tree felling and pond-making are good for the environment—unlike humans, who chop down lots of trees and make artificial ponds when landscaping, while simultaneously draining wetlands, which doesn’t help the local environment at all. Besides, the beavers are cute and attract tourists who want to get pictures of them, which is also good for the local economy. Everybody wins when there are beavers around, is what I’m trying to say.

The beavers reintroduced in 2009 aren’t the only beavers in Scotland. In 2001, people started seeing them around the river Tay—but no one knew where they came from. Well, presumably someone knew, because the beavers didn’t get there without help. If this reminds you of episode 48, where we talked about some mystery beavers that appeared in Devon, England, the Devon beavers showed up in 2013, twelve years after the Scottish mystery beavers. At first the Scottish government planned to capture the Tayside beavers and keep them in captivity, but the beavers are still there and doing very well.

It’s great that over a thousand beavers live in Scotland now, but that’s actually not very many. Still, it’s a whole lot better than the number of Eurasian beavers about 150 years ago, when researchers think there may have been as few as 300 individuals alive in the whole world.

Another animal that once lived in Scotland, was hunted to extinction, and then mysteriously reappeared recently is the wild boar. They first appeared in the 1990s and by now there are thousands of them in Scotland. It’s possible they escaped from farms, where they’re sometimes raised for meat like domestic pigs. While they’re a native species, they don’t have any predators in Scotland and are causing a lot of damage as they become more numerous. The wild boar’s natural predator is the wolf, and the last wolf in Scotland was killed in 1743. Lynxes will also kill wild boar piglets.

Some birds have been reintroduced to Scotland too. The white-tailed eagle is a type of sea eagle, closely related to the bald eagle of North America although it’s slightly larger than the bald eagle. The biggest ever reliably measured was a specimen from Greenland with a wingspan of 8 feet 4 inches across, or 2.53 meters, just a smidge larger than the largest bald eagle wingspan known. It’s mostly brown and gray with a yellow bill and feet, and a white tail. It lives around water and eats a lot of fish, but it also eats lots of carrion, gulls and other birds, and occasionally small mammals like rabbits. It always lives near water but it prefers wooded areas, especially lowlands and forested islands.

The white-tailed eagle went extinct throughout Britain in the early 20th century when people decided they wanted all those fish the eagle eats for themselves. Never mind that even a thousand eagles couldn’t eat as many fish that a single commercial fishing boat catches in a day. People also decided that eagles killed lambs, even though this is extremely rare. White-tailed eagles would much rather eat fish and seagulls than lamb. The last white-tailed eagles in Scotland were shot and killed in 1916.

As if that wasn’t bad enough, white-tailed eagles were also killed throughout the rest of their range and were especially vulnerable to the chemical called DDT. DDT was a popular pesticide developed in the 1950s and used to kill insects on crops and gardens. But DDT is dangerous, because like other pesticides it doesn’t just do its job and evaporate. It stays in the environment and ends up in the bodies of animals, including people. It’s especially bad for birds that eat a lot of fish, since a lot of pesticides end up in the water, and it causes their eggshells to become so thin and weak that the eggs break when the mother tries to keep them warm. This is the same thing that almost drove the bald eagle to extinction in North America. By the time DDT use was banned in many countries and the white-tailed eagle was declared a protected species, it was almost too late.

Conservation efforts have helped stop the white-tailed eagle from going extinct and its numbers are slowly growing. Starting in 1975, young eagles were brought from Norway to Scotland, where they were successfully reintroduced in the inner Hebrides islands and have now expanded to other parts of Scotland. Some people still complain about the eagles and sometimes shoot or poison them even though it’s illegal, but most people are happy to have them around, especially birdwatchers.

Scotland even has some reindeer these days. Reindeer probably lived in Scotland until around the 12th century, and in 1952 a Swiss herdsman thought they should still be there. He brought a small herd to the Cairngorm mountains, which is now a national park. The reindeer are semi-domesticated but roam free, and they attract tourists who hope to catch a glimpse of them.

At the same time that many native animals have gone extinct, lots of non-native animals have been introduced to Scotland, including wallabies, American mink, gray squirrels, various species of crayfish, and many more. Conservationists are working to minimize the damage these introduced species cause. Many invasive species were animals kept as pets that either escaped or were released into the wild. We talked about the invasive eastern gray squirrel versus the native red squirrel in episode 241, for instance. People released gray squirrels into parks in England because they were so cute, and a hundred years later, the gray squirrels are taking over in many places. They’re increasingly common in Scotland, although Scotland has a small predator called the pine marten that loves to eat squirrels.

The pine marten is a type of mustelid, or weasel relative, that’s common throughout much of Europe and Asia. It grows about two and a half feet long, or 75 cm, including its bushy tail. It mostly lives in wooded areas and spends a lot of its time in trees, hunting squirrels and other small animals like frogs, insects, and birds. It will also eat carrion, bird eggs, and sometimes fruit. It’s mostly brown with a cream-colored throat. It even has partially retractable claws like a cat to help it climb trees, although it’s not related to the cat.

The pine marten is especially good at catching squirrels, and it tends to target the gray squirrel because it’s easier to catch. The red squirrel is more cautious. Where there are pine martens, there are fewer or no gray squirrels. The problem is, the pine marten is considered a pest that kills game birds, so some people shoot or poison it even though it’s a protected species. Then those same people complain about all the gray squirrels around. The pine marten is doing well in many parts of Scotland, though, and has even expanded its range slightly in the last few years.

Scotland is a beautiful country known for its wild and rugged countryside. It wouldn’t take much to rewild it properly, a process that’s well underway with keystone species like beavers already re-established in many places. The main problem is people who don’t understand that a healthy ecosystem requires predators. Without lynxes, wolves, bears, and other large predators, animals like roe deer and wild boar become so numerous that they can’t find enough to eat and either starve or destroy crops and gardens.

Fortunately, many more people in Scotland do understand the importance of building healthy ecosystems. After all, they’re naturally proud of where they live and want to make it even better.

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 017: Thunderbird

We’re talking about Thunderbird this week and the huge North American birds that may have inspired Thunderbird’s physical description. Thanks to Desmon of the Not Historians podcast for this week’s topic suggestion!

Further listening:

While I was in the middle of researching this episode, Thinking Sideways did a whole episode on Washington’s Eagle.

Further reading:

“The Great Quake and the Great Drowning”

“The Myth of 19th Century Pterodactyls”

Depiction of Thunderbird on a Pacific Northwest totem pole:

A wandering albatross hanging out with a lot of lesser birds. Biggest wingspan in the world right here, folks!

A California condor. #16, in fact.

An adult bald eagle with a juvenile.

Washington’s eagle as painted by James Audubon

Model of a teratorn. We don’t actually know what colors they were.

Show transcript:

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

This week’s episode about Thunderbirds was suggested by Desmon of the Not Historians Podcast, a fun, fascinating podcast about history. If you haven’t given it a listen yet, I recommend it.

Despite my interest in birds, before I started research for this episode, I didn’t know much about the Thunderbird. I knew it was an element in First Nations lore but I didn’t know which tribes or regions, just assumed it was out west somewhere. Since I live in East Tennessee, “out west” to me is a vague wave of the hand and a mental image of wide-open plains and buffalo and maybe John Wayne. But it turns out that the Thunderbird is an important element in Northeastern and Pacific Northwest tribal lore, as well as being well known among the Great Plains societies and beyond. Thunderbird, in fact, is one of the most widespread figures in Native American lore.

I’m always cautious when mystery animal research points me to religious lore. Many cryptozoologists like to mine myths, legends, folktales, and religious stories of all kinds to find corroboration for the existence of their personal pet cryptid, but if you aren’t extremely well versed in the culture, it’s easy to misinterpret elements of a story. Worse, some cryptozoologists do this on purpose, running roughshod over sacred beliefs and yanking out one mention of, for instance, a giant human and then shouting about how this tribe clearly knows all about Bigfoot. Not to pick on the Bigfoot hunters, but guys, you need to calm down.

Thunderbird is associated with storms but it’s not accurate to say he’s a storm god. He’s more of a representation of the uncontrollable power of nature. In many Plains societies, Thunderbird is associated with trickster figures and a deep belief in the dual aspect of nature—that things in nature often hold their own opposites, that everything found in nature is reflected and represented in the human world.

Thunderbird is not necessarily a single being, either. Many tribes have stories about four different varieties of Thunderbird represented by different colors. Sometimes the different colored Thunderbirds correspond to the cardinal directions, sometimes not. And while Thunderbird is generally supposed to be an enormous eagle-like bird, the difference between bird and human is frequently blurred in the stories. This blurring of human and animal traits in stories is true across all cultures, incidentally, and if you doubt me, think about “what big eyes you have, granny.” Animal beings in traditional stories of all types are allegories, not real animals or real people.

The Thunderbird is also an allegory, a spiritual being, and it’s a disservice to the rich and sophisticated First Nations cultures to strip those trappings away and try to find nothing but a bird underneath. That’s not to say the physical form of Thunderbird wasn’t inspired by eagles or other birds. Just don’t dismiss a culture’s spiritual world to root out so-called proof of a natural explanation.

But. That doesn’t mean there aren’t any gigantic honkin birds in North America and throughout the world.

Going by wingspan, the biggest known living bird is the wandering albatross. Its wingspan can exceed 12 feet, with unconfirmed rumors of individuals with wingspans topping 17 feet. That is an enormous wingspan, seriously. I’d love to see one. The wandering albatross looks like an enormous seagull, white with black wings and a pink bill and feet. Males have more white on the wings—sometimes only the wingtips are black—and a peach-colored spot behind the head. Like many seabirds, albatrosses have a salt gland in their nostrils that helps filter excess salt from the body.

The wandering albatross spends most of its life on the wing far out at sea. It can soar for hours without needing to flap its wings. It eats fish and other animals it can catch at the surface of the ocean or in shallow dives, and sometimes will eat so much it can’t fly and has to sit in the water while it digests. I feel that way every time I go to a buffet.

But since the wandering albatross, as well as its somewhat smaller relatives, lives around the southern sea at the south pole, I think we can safely say that it wasn’t an inspiration for Thunderbird. Besides, it’s basically a giant seagull. Not exactly Thunderbird material.

The California condor’s wingspan is ten feet, and many people point at it as a possible Thunderbird model. But the condor is a type of vulture, which means it has a bald head and mostly eats carrion. Vultures evolved bald heads to reduce bacterial growth in their feathers, since yeah, they sometimes stick their heads in dead animal carcasses to get at those yummy soft parts. No matter how magnificent a wingspan the condor has, it doesn’t fit the stories of Thunderbird battling creatures like Horned Snake, since vultures aren’t raptors and their bills and claws are relatively weak. The same holds true for the Andean condor, with a wingspan of eleven feet, not to mention that bird lives in South America.

The trumpeter swan has a wingspan of over ten feet and lives in North America, but while swans can be aggressive, they eat aquatic plants and act like gigantic ducks, not exactly fierce Thunderbird material. The American white pelican likewise has a ten-foot wingspan but, well, it’s a pelican.

So what about North American eagles? We only have two known species, the bald eagle and the golden eagle. Both have wingspans that can reach more than eight feet and, tellingly, both are common throughout the Pacific Northwest and throughout most of North America. It’s entirely possible that admiration of these large eagles gave form to descriptions of the Thunderbird.

But while an eagle with a nine foot wingspan is impressive, let’s not fool ourselves. We all want to know about GIANT HECKIN HUGE BIRDS. Like, twice that size! This is what cryptozoologists so often dig around for in Native Thunderbird legends, hints that there was once and maybe still is a bird so enormous that it inspired terror and awe in people who saw it, to the degree that they immortalized it in cultures throughout North America as the Thunderbird.

In cultures without written language, stories impart knowledge of everything—history as well as religion, warnings of real-life dangers as well as rituals to ward off the danger—and many stories serve dual purposes. Among the Pacific Northwest peoples, certain stories about Thunderbird battling Whale commemorate a cataclysmic event now known to science, a violent earthquake on Jan. 16, 1700. It was probably a magnitude 9 quake that dropped the coast as much as six and a half feet and resulted in tsunami waves drowning villages from northern California to southern Vancouver Island. In the 1980s a team of researchers studying the geology of the area looked closely at stories of the Makah people in Washington state. Soon they learned that all the indigenous peoples along the coast had stories about the earthquake.

The difference between that study and cryptozoologists looking for Bigfoot or a real-life Thunderbird is one of training and intent. The 1980s team consisted of anthropologists, geologists, and indigenous scholars. And they weren’t cherrypicking information that matched what they had already decided was the truth. What they discovered among the Pacific Northwest peoples guided their research and helped them learn more about the infrequent but violent earthquakes in the area. They even uncovered stories that may be about older quakes and tsunamis.

The problem is that stories about events that happened a long time ago tend to fall out of circulation eventually, especially if the events are no longer relevant. The earthquake stories were hard to gather in the 1980s because the event that inspired them happened almost 300 years before. How much can you remember about the year 1700 without looking it up online? And in the meantime, other cataclysms, notably invading Europeans bringing diseases like smallpox, destroyed much of the native culture.

In other words, even if you’re a trained anthropologist with a deep understanding of the cultures you’re studying, teasing historical information about giant birds from Native American stories is next to impossible. We know truly gigantic birds used to exist in North America because we’ve found their remains, but we can never know for certain if any of those birds inspired Thunderbird legends in any way or if the birds were ever even seen by humans.

Some of the largest flying birds that ever lived are known as pseudotooth birds because their beaks had toothlike spines. They were big, slender birds that probably looked a lot like albatrosses although at the moment they’re classified as more closely related to storks and pelicans. While we don’t have any complete skeletons, researchers estimate the birds’ wingspans may have been as much as 20 feet. One species, Pelagornis sandersi, may have had a wingspan as wide as 24 feet. I just went outside and measured the road in front of my house, and it’s only about 18 and a half feet wide, just to put that into perspective. It’s probable the pseudotooth birds weren’t actually able to flap their wings, just soar.

Like albatrosses, the pseudotooth birds probably covered vast distances in flight. Their remains have been found in North and South America, New Zealand, parts of Africa and Europe, Japan, even the Antarctic. They ate whatever they could scoop up from the water with their long bills. The toothlike projections on their bills weren’t very strong and just helped the bird keep hold of wriggly fish, but they certainly look impressive.

But from what we know from the fossil record, the pseudotooths all died out by the early Pleistocene, some two million years ago. Homo habilis may have seen them flying off the coast of Africa, and if so I bet our distant ancestors thought something like, “Wow, that’s a huge bird!”

The group of North American birds that a lot of cryptozoologists want to call the Thunderbird is the teratorns. Some of them were as big as pseudotooth birds with 20-foot wingspans, but they looked much different. They’re related to the New World vultures, but their bills are more eagle-like, indicating that teratorns were active hunters that could probably swallow prey as large as rabbits whole. Formerly some researchers thought the biggest teratorns couldn’t fly, but new discoveries of fossils with contour feather attachment marks indicate they could. But since teratorns had long, strong legs as well, they might have sometimes stalked their prey on foot the way golden eagles occasionally do.

We have a lot of teratorn remains from the La Brea tar pits. Teratornis merriami had a wingspan of about 12 feet and lived until only about 10,000 years ago. The biggest teratorn is Argentavis magnificens, which lived in South America and probably went extinct around 6 million years ago. It had a wingspan of at least 20 feet, possibly more than 25 feet, but we don’t have very many fossils of this bird. Only one humerus has been discovered—that’s the upper arm bone, and it’s the length of an entire human arm.

It would be truly magnificent if a teratorn descendent still existed. Some people think it did, at least until a few hundred years ago. We might even have a depiction of one by the most famous bird artist in the world, James Audubon.

In February 1814, Audubon was traveling on a boat on the upper Mississippi River when he spotted a big eagle he didn’t recognize. A Canadian fur dealer who was with him said it was a rare eagle that he’d only ever seen around the Great Lakes before, called the great eagle. Audubon was no slouch as a birdwatcher and was familiar with bald eagles and golden eagles. He was convinced this great eagle was something else.

Audubon made four more sightings over the next few years, including at close range in Kentucky where he was able to watch a pair with a nest and two babies. Two years after that, he spotted an adult eagle at a farm near Henderson, Kentucky. Some pigs had just been slaughtered and the eagle was probably coming by to look for scraps. Audubon shot the bird and took it to a friend who lived nearby, an experienced hunter, and both men examined the body carefully.

According to the notes Audubon made at the time, the bird was a male with a wingspan of 10.2 feet. Since female eagles are generally larger than males, that means this 10-foot wingspan was likely on the smaller side of average for the species. It was dark brown on its upper body, a lighter cinnamon brown underneath, with a dark bill and yellow legs.

Audubon named the bird Washington’s eagle after George Washington and used the specimen as a model for a lifesized painting. Audubon was meticulous about details and size, using a double-grid method to make sure his bird paintings were precisely exact. This was long before photography, remember.

So we have a detailed painting and first-hand notes from James Audobon himself about an eagle that…doesn’t appear to exist.

Now, this isn’t the only bird Audubon painted that went extinct afterwards. He painted the ivory-billed woodpecker, subject of our episode nine, and the passenger pigeon, along with less well known birds like Bachman’s warbler and the Carolina parakeet. Yeah, North America used to have its very own budgie that was cute as heck, but it’s long gone now.

To add to the confusion, though, Audubon also made some mistakes. Selby’s flycatcher? Nope, that was just a female hooded warbler. Many people think Washington’s eagle was just an immature bald eagle, which it resembles.

I don’t actually agree. I’m just going to say that right out. Let me explain why.

There are reports of bald eagles with wingspans of nine feet, although I couldn’t find any verified measurements that long. A bald eagle will actually have a slightly wider wingspan as a juvenile than as an adult because of the way its feathers are arranged, but that difference is a matter of a few inches, not feet. In addition, the largest bald eagles are found in Alaska; individuals in the southeastern United States are usually much smaller. And female bald eagles are typically as much as 25% larger than males.

But here we have a male eagle shot in Kentucky with a measured wingspan of 10.2 feet. Juvenile bald eagles do travel widely, but even if that happened to be an outrageously large individual who’d flown down from Alaska, consider that Audubon had seen the same type of eagle nesting a few years before near the same area. He’d watched a pair feeding two chicks. Immature bald eagles don’t nest or lay eggs. There are other differences too, notably the color and size of the nostril area and the type of scaling on the legs.

Golden eagles also resemble juvenile bald eagles to some degree, but they don’t nest in Kentucky. Their winter range just barely touches Kentucky, in fact. They nest in Canada and in the western half of the United States. And the largest golden eagle ever measured was a captive-bred female with a 9.3 foot wingspan, and like bald eagles, golden eagle females tend to be considerably larger than males. A male with a wingspan of over ten feet is probably not too likely; but even if an aberrantly large male golden eagle decided to vacation a little farther south than usual, it’s clear from many details in Audubon’s painting and in his notes that the bird he shot can’t be a golden eagle.

Audubon kept diaries of his birding trips so we know he was familiar with juvenile bald eagles—he even painted one. We also know he differentiated between juvenile bald eagles and Washington’s eagle, which he wrote was about a quarter larger than the juvenile bald eagle.

And Audubon wasn’t the only person to have reported the eagle. From other reports we know it hunted differently from bald eagles, including no reports of it stealing fish from ospreys the way bald eagles frequently do (the jerks). Washington’s eagle reportedly preferred to nest in rocky cliffs near water, not in trees like bald eagles.

So I don’t think Audubon was mistaken or lying. I think he really did paint a type of eagle that was already rare in the early 19th century and which went extinct soon after. Unfortunately, Audubon’s mounted specimen has been lost, but it’s always possible there are other specimens floating around in personal collections or museum storage rooms, possibly mislabeled as juvenile bald eagles.

There’s not a very good chance that Washington’s eagle survived into the present day just because its immense size would make it easy to spot. Then again, size is really hard to estimate without something of known size to compare it to. Is it a gigantic eagle that’s really high up or an ordinary eagle at a closer distance? Combine that with Washington’s eagle looking so much like a juvenile bald eagle and there could be a remote population hiding in plain sight.

There are, of course, lots of reports of giant birds in North America. Most take place along roads or in back yards, where people catch glimpses of eagles of unbelievable proportions—literally unbelievable, in fact, 15 or 20 or even 25-foot wingspans and birds that pick up deer and fly off with them. Most of these are probably misidentifications of known birds of prey with size exaggerated due to alarm, poor visibility, or just an inability to estimate size correctly. Some may be hoaxes. But there’s always the possibility that in this case we might really have a very rare, very large eagle still living in remote areas of Canada or Alaska, and occasionally one flies into more populated areas.

Let’s hope someone finds some remains, either taxidermied specimens or a collection of bones and feathers in some protected cave, so they can be tested and we can find out if there’s a real live teratorn still flying around—or at least learn if there are three species of eagle in North America instead of just two.

I don’t know if Washington’s eagle has anything to do with the Thunderbird. In my mind they feel like two completely separate entities: a flesh and blood eagle circling high above a lake in search of prey, and a terrifying being wrapped in storm clouds soaring somewhere between reality and the spirit world. Some birds are bigger than others, and some birds have to be taken on faith.

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!