The Science of Birds - The Shoebill

Episode Date: June 10, 2021

The Shoebill is a tall, gray bird that appears more dinosaur-like than most members of the class Aves. You aren’t likely to confuse it with any other bird. It possesses a unique and impressive combination of size, color, and bill shape.The Shoebill is a top predator in certain kinds of swamps and wetlands in Africa. It terrorizes not only large fish, but other small aquatic animals, like amphibians and reptiles.This almost mythical beast of a bird is one of the most exciting species in all of Africa.This episode is all about the Shoebill, Balaeniceps rex. What it looks like, where it lives, how it behaves, and its conservation status.~~ Leave me a review using Podchaser ~~Links of InterestVideo of Shoebill chicks competing for attention at the nestLink to this episode on the Science of Birds websiteSupport the show

Striding quietly and deliberately through an African swamp, King Whalehead searches for his next victim. In the dark pools between clumps of papyrus sedges, he hopes to find a fat fish to snatch up with his massive beak. The name King Whalehead is a translation of the scientific name of his species, Balinaceps Rex. But only his friends call him King Whalehead. You and I know him better as the Shoe Bill. This tall, gray bird appears more dinosaur-like than most members of the class Aves. You aren't likely to confuse it with any other bird. It possesses a unique and impressive combination of size, color, and bill shape.

The Shoe Bill is a top predator in certain kinds of swamps and wetlands in Africa. It terrorizes not only large fish, but other small aquatic animals, like amphibians and reptiles. The swamps haunted by shoebills were, at least historically, so remote and inaccessible that European naturalists didn't, quote-unquote, discover this species until the mid-1800s. The famous English ornithologist John Gould wrote a paper in 1851 describing this bird, to Western science for the first time. In his paper, Gould assigned the shoebill the scientific name of Bolina Seps Rex and said it is, quote, the most extraordinary bird I have seen for many years, end quote.

That's a bold statement coming from a guy who had seen quite a few amazing birds in Australia and beyond. Also, I'm pretty sure I nailed that impressin of John Gould. You can probably tell I've been practicing a lot. Of course, native Africans, including the Egyptians, had long been familiar with the shoe bill. In Uganda, this bird is called Bulwe. Arabs named it Abu Markub, which supposedly means father of the shoe. I tried typing Abu Markub into Google Translate, but it didn't give me anything like father of the shoe.

Not sure what to make of that. In any case, Germans may have taken their cue from the Arabs because they call this species Shushnabu, which means Shoebeak. For a long time, English speakers refer to this bird as the whale-headed stork, or whalebill. But the footwear reference is just so fitting that the name Shoe Bill has finally won out. I suppose if the shoe fits, wear it. Hello and welcome. This is the Science of Birds.

I am your host, Ivan Philipson. The Science of Birds podcast is a lighthearted, guided exploration of bird biology for lifelong learners. This episode is all about the shoebill, Baliniceps, Rex. What it looks like. where it lives, how it behaves, or in some cases doesn't behave, and its conservation status. This almost mythical beast of a bird is one of the most exciting species in all of Africa. So let's get moving. Let's wade our way into the quagmires of tropical Africa to learn about the rare and remarkable shoebill. If you don't already have a mental picture of what a shoe bill looks like,

let's see if we can remedy that. This is a large and robust bird. It has a stork-like body shape and stands over four feet tall, with some individuals possibly pushing five feet, or 1.52 meters. There are taller bird species in the world, but still, the shoebill is pretty impressive. Its plumage is a mostly uniform, bluish-gray color, with slightly darker flight feathers. The shoebill's wingspan is up to eight feet, which is about 2.4 meters. The wings are broad and well-suited for soaring.

The first time I saw a wild shoe-bill, that's what it was doing. It was soaring on thermals high over the swamp, gliding like a vulture without flapping its wings much. In fact, the shoe bill has one of the slowest flapping rates of any bird, only about 150 beats per minute. That might sound like a lot until you realize a hummingbird can flap its tiny wings over 4,500 times a minute. Shoebills tend to be sedentary. They stick around in the same general area year round. So even though they're good at soaring, they don't normally fly long distances. Their flights are usually pretty short, really just little hops from here to there around the swamp. Shoe bills hang out on their own mostly.

They're loners, solitary creatures that stand still for long periods of time or move around sluggishly in the waterways of their swampy kingdoms. Now, what about that massive bulging bill? That's what we all want to know about, right? Indeed, it does have a shoe-like shape. Some say it looks like a wooden Dutch clog, if you have any idea what that looks like. The bill is between 9 and 12 inches long, making it the third longest beak among modern-day birds. The shoe bill's bill is, however, as far as I know, the thickest in the world.

It's number one in that category. No other bird species has a bill with a greater circumference. The tip of the upper bill has a hard, hook-like tip. This is a structure we call the nail. It helps the shoe bill snag its prey. Color-wise, the shoe bill's bill is a sort of fleshy or pinkish color, with lots of random gray modeling on its surface. That enormous bill protrudes from the bird's large head. There's a messy little tuft of feathers that sticks out at the back end of the shoebill's head. A pair of large yellow eyes give the shoebill a raptorial, piercing gaze. Supra-orbital ridges jutting out over the eyes add to the menacing appearance.

They give the shoe bill a sort of furrowed brow look, like it's angry and about to say, What are you looking at? Mind your own business, you NeNehammer. You and your stupid binoculars can just get right on out of my swamp. Don't make me come over there. I'll I'll flap over there slowly and give you a stern look, I will. But this is just projecting our human facial expressions on to an animal, isn't it? The shoe bill can't move the muscles of its face around the way we can. It's just sort of stuck with that one expression. It wears a scowl 24-7, even when it's feeling happy,

like when it just caught an enormous fish, or when it sees a bunch of puppies and kittens frolicking underneath a rainbow. So, giant bill, yellow eyes, little tuft of feathers sticking out the back, permanent scowl, all of that on a big fat head. At the opposite end of the bird are its very large feet with their extra long toes. These probably help the shoe bill walk around more easily on mats of floating vegetation or on mud. All of these physical traits are similar between males and females. There isn't much sexual dimorphism in the shoe bill. So if you're out in the swamp and you come across one of these beasts,

you have no good way of telling whether you're looking at king whalehead or queen whalehead. As for sounds, well, this species doesn't make too many. It's mostly silent. However, during nesting season, these birds will make a clattering sound with their bills. It sounds sort of like a distant machine gun or a motorcycle. engine. Apparently, the shoe bill can also make some low, guttural vocal sounds. So, I hope you have a better mental image of this spectacular bird now. I'll include a photo or two in the show

notes for this episode on the Science of Birds website. And of course, you can do a quick Google search to see a million and one shoebill photos. Balinaceps rex is the only species in the avian family Balena sepidity That's Balinacipidity So this family is monotypic It contains only one genus And that genus contains only one species

The Shoebill You'll often hear people saying stuff like The Shubill is a prehistoric-looking bird That proves birds really are dinosaurs Or, they are the closest thing we ever come to seeing a real-life dinosaur. That second one with the poor grammar is an actual comment I saw on a YouTube video of a shoebill. But Balina Seps rex, b-rex, if you will, isn't any more closely related to T-Rex than an

Ospre, a pelican, or an owl. We could make a better argument that chickens and hummingbirds are closer relatives of all those big lizards in Jurassic Park. So actually, a chicken might be the closest thing we ever come to seeing a real-life dinosaur. And all birds are dinosaurs, right? Some represent more ancient lineages than others. The more ancient a bird lineage is, the more dinosaur-like we might say it is. But in any case, just because a bird is big and looks like it wants to murder you, doesn't mean it's more of a dinosaur than any other bird. Anyway, as the only member of its family, the shoe bill is unique.

It's not closely related to any other bird on the planet. But people have, for a long time, referred to it as a stork. You'll still come across references that call it a shoebill stork. Once upon a time, in 1977, the well-known paleornatologist Alan Feduccia published a paper in the prestigious journal, Nature. The paper was titled, The Whale Bill is a stork. Feducia based his argument on comparisons of the earbone of the shoe bill

with those of other birds. First off, did you know you could be a paleoanithologist when you grow up? It's like paleontology, but with birds. Pretty cool. Second, it turns out the shoe bill is not a stork. We know that now because genetic data has, more recently, given us a much better picture of which bird families are related to which. Genetic data tells us that shoe bills are definitely not storks.

In hindsight, the peremptory tone of that paper title, The Whale Bill is a stork, seems embarrassingly overconfident. Poor Alan Feduccia. He's better known as the guy who has made a career out of denying that modern birds are direct descendants of theropod dinosaurs. I won't get into it now, but Feduccia has his own hypotheses about the origin of birds. Let's just say he's ruffled a few feathers in the community of mainstream ornithologists. The shoebill may not have close relatives, but its closest relative is the hammer cop,

another weird and wonderful African bird. Hammer cop means hammerhead in the Afrikaans language. This much smaller bird is chocolate brown and really does have a funny shaped head with an odd swept-back crest of feathers. The hammer cop too is the only member of its family, scopidae. The two families, Balena sepidity and scopedi, belong to a larger lineage of birds, the order Pelicaniformis. Your acute perspicacity has no doubt led you to the conclusion that the Order Pelicaniformis

must also include the Pelican family. In this, you are correct. Storks, I should also point out, are not in the Order Pelicaniformis. Okay, so you know that the shoebill is an African bird, but what is its range, more specifically? It has a fairly large range in tropical, sub-Saharan Africa, mostly east of the Congo basin. The largest populations are found in South Sudan. You can also find shoebills in Uganda, Tanzania, and south to Zambia. Within this broad geographic range, shoebills are distributed only locally. They're spread thin across the continent, living their solitary lives in very specific habitats. They prefer to live in papyrus swamps. Papyrus is an aquatic sedge that forms tall stands in shallow freshwater habitats.

In deeper water, it often forms a tangled, floating mass of vegetation called sud. That's S-U-D-D. You probably know that papyrus is the plant that ancient Egyptians used to make paper. Papyrus grows in flooded swamps along stream beds or the margins of lakes like Lake Victoria. Shoebills living in these swamps prefer to wade around in the more open channels, between stands of papyrus and other thick vegetation. With their broad wings, shoebills need a bit of elbow room when they take to the sky. These channels through the swamp are sometimes the handiwork of hippos or elephants.

The massive mammals sort of landscape the swamp as they forage and travel through the area. Many of these wetland habitats preferred by the shoebill experience seasonal flooding. When things start to dry out a bit, when the floodwaters recede, fish in the swamp become concentrated in the shrinking pools and channels. They become easy prey for hungry, hungry shoebills. And now I feel like I need to say something about hungry, hungry hippos, because those guys are also in the swamp, wallowing and sloshing around, making channels and whatnot,

as we just discussed. But the hippopotamus doesn't eat fish. It prefers to eat grasses and plastic marbles. The IUCN Red List has the shoe bill in the vulnerable category. It's estimated that there are only 5,000 to 8,000 individuals, and this number is decreasing. The primary threats causing the decline of shoebills are hunting, nest disturbance, and habitat destruction and modification. Swamps are drained for agriculture, and cattle trample nests and just generally trash shoebill habitats. And wildfires started by humans are a major problem as well.

Shobills are also captured and traded, either illegally or legally, depending on the country. Captured individuals end up in zoos or in the hands of nefarious private collectors. There are multiple efforts being made to help shoebills. In places where this species habitat is protected, it has higher breeding success. So habitat protection is incredibly important. Local fishermen have been hired in at least one location to guard shoebill nests from disturbance and poachers. Ecotourism may also help shoebills by giving local people an incentive to protect and celebrate these birds. Crazy birders like me will happily pay local guides to show them a shoe bill.

It's one of the most sought-after bird species on the African continent. Ideally, people sharing the land with shoebills will come to see the power of ecotourism to view the living birds and their healthy habitats as having the highest economic value. Earlier I described the unique clog-like beak of the shoebill, but we didn't really get into how it uses that beak. So let's look now at what and how the shoe bill eats. Its absolute favorite prey is the marbled lungfish, protopterus Ethiopicus. This is a thick, cylinder-shaped, long-bodied fish.

It can get up to over six feet long, or two meters. The marbled lungfish and other types of lungfish have a specialized respiratory system that allows them to breathe air when they need to. In other words, they have primitive lungs. And of all fish, lungfish are the most closely related to terrestrial vertebrates like reptiles, frogs, raccoons, and you. lungfish can survive well in freshwater habitats with low levels of oxygen in the water. When they can't get enough oxygen from the water, lungfish just come to the surface to

gulp some air into their little lungs. It's probably no coincidence then that shoebills tend to live in poorly oxygenated swamps, where all those juicy lungfish are right at the water surface. They're ripe for the picking. Other fish are certainly on the menu. for shoebills, catfish especially, but also tilapia. And look out amphibians, snakes, and baby crocodiles, you too are likely to end up in a shoebill stomach if you are not wary enough. It seems even turtles, rodents, and other birds like ducks will sometimes get swallowed by a shoebill. The shoe snobble, our shoebill, has two primary foraging strategies. The first is to just sit and wait. Well, actually, stand and wait. The bird just stands motionless and pears into the

dark water at its feet. As an outside observer, you might think you're looking at a statue of a bird. The shoe bill is sort of like those weird guys who paint themselves silver and stand perfectly still in public parks. But in most cases, the silver painted guys don't try to eat you if you get too close. In one shoebill population, researchers quantified the time the birds spent engaging in various activities. It turned out that they are pretty low-energy critters. They spend 85% of their time standing still or preening. The second shoe-bill foraging strategy is to wade and walk. The bird methodically and languidly moves through its territory, again looking down into the water as goes. As in war, these long periods of boredom are punctuated by moments of terror,

terror for the fish and other small animals of the swamp, that is. When the shoe bill zeroes in on its prey, it suddenly lunges forward with its massive head. It flaps its wings and snaps its bill on the prey animal in a burst of speed and power. The shoe bill's forward momentum is so forceful that it may topple over after the attack. Researchers actually describe these attack events as collapsing. The prey animal is engulfed along with a bunch of water and maybe some floating vegetation. The shoe bill will often tilt its head side to side to dump out the water and the flotsam while still gripping the prey. The lungfish, catfish, or whatever is crushed in the mighty bill. The edges of the upper mandible are

are sharp and blade-like. Shoebills often use their sharp bill like a guillotine to decapitate their wriggling prey before swallowing it whole. The handling time, the amount of time it takes from capture to horking the prey down the gullet, is four to seven minutes or so. So it takes quite a while to do all that water dumping, prey manipulating, and head-cutting-offing. You might wonder if the shoe bill is itself,

prey for some other larger animal? Apparently not. As far as I know, there aren't any predators that eat adult shoebills, at least not with any regularity. Maybe the occasional Nile crocodile would opportunistically snatch an unwary shoebill. Young shoebills are probably more vulnerable, and their eggs may be eaten by a variety of sneaky predators. While an adult shoebill is mostly immune from predation, it may still have its lunch stolen by another animal. A study of shoebills in a Tanzanian population found that 47% of their successful prey captures were stolen by African fish eagles. An eagle could see a collapsing shoebill from a distance, then it would swoop in to rob the catch. In over 100 instances of this

kleptop parasitism, the victimized shoebill never retaliated. It just gave up its lunch to the eagle. Unlike storks, herons, and pelicans, shoebills do not nest in breeding colonies. They are very solitary birds. They form monogamous pairs in the breeding season, and both parents care for the chicks. But these birds are such loners that the male and female are rarely ever at the nest at the same time. It's like they're a divorced couple who have a co-parenting agreement. Mom gets the kids Monday through Friday, and dad has them on the weekends and every other Christmas.

The shoebill nest is made of grassy vegetation on a mound of floating plants, a big mess of that sud stuff. Or the nest might be built on a small island. The nest is big. It's up to three meters across. Shoebills tend to place these nests out of sight, deep in the papyrus stands. There are one to three eggs. Two is typical. To keep the eggs cool in the tropical heat, the parents will fill their capacious beaks with water and pour it out over the eggs. The parents tend to their nest for 95 to 105 days before the chick's fledge. Or I should actually say before the chick fledges.

Because, you see, only one chick is likely to survive. The shoebill nest is like the Thunderdome in Mad Max. Two chicks enter, one chick leaves. The chick that hatches earlier is usually given more food and attention. It gets stronger while its younger sibling

gets weaker. With seeming cruel indifference, the parents eventually ignore the weaker nestling. The older chick may even actively attack the younger one. It's pretty brutal and sad. But we probably shouldn't judge the shoebills too harshly. They have these behaviors because they work in the evolutionary sense. This does make me scratch my head, though. If only one chick survives, the shoebill population would inevitably decline, right? So on average, there must be some families that produced at least

three chicks to compensate, to keep the population in balance. If shoe bills have been producing only one chick per family for thousands of years, we wouldn't have any shoe bills. In any case, a young shoe bill stays with its parents for at least another week after it leaves the nest, perhaps much longer. But eventually, it's left to fend for itself. It will take about three years for a shoe bill to reach sexual maturity. Estimates of a shoe bill's life range from 35 to 50 years. But birds in captivity are more likely to make it into their golden years. Life in the wild is rough and relatively short. Someone recently asked me what my favorite bird is. I laughed and said, that's not easy to answer. I have a bunch of favorite birds.

So they changed the question to What was your best bird experience? I thought for a moment and then told them about seeing a shoe bill in Uganda. The first time I went to Uganda to lead a nature-slash-birding tour, we went to look for the shoe bill in a swamp on the northern shore of Lake Victoria. I mean, you can't not go look for the shoe bill when you're in Uganda, right? So we got into these little canoes with some local guides and motored around in the channels between dense papyrus stands.

That's when I got to see a shoe bill only at a great distance as it soared far overhead. Pretty cool, but not a super satisfying view. On my next trip to Uganda, I had a much better experience with this bird. We ventured into the same swamp and, Behold! There was King Whalehead, the mighty B-Rex himself. or herself. I have no idea whether the bird was male or female. But it was close, and it stood still for the approximately 2,000 photos I took of it. It was glorious. At one point, the bird turned its head to look directly at us, and I was on the receiving end of that fearsome glare. It was an

absolutely magical experience. The shoe bill is, to once again quote John Gould, the most extraordinary bird I have seen for many years. I hope you enjoyed this episode on the fascinating shoe bill. Thanks for hanging out with me today and to do some bird learning. If you have thoughts or feelings about the show, or if you have a story about that time you narrowly escaped the clutches of a silver statue guy in the park, well, shoot me an email. The address is,

at Scienceofbirds.com. You can see the show notes for this episode, which is number 30, on the Science of Birds website, scienceofbirds.com. This is Ivan Philipson, and I'll catch you next time. Peace.