10 Fun Facts About Pelicans

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Here’s a scoop for you: Pelicans are awesome. They’ve got interesting feet, spectacular hunting habits, and throat pouches that can trap a lot more than fish. Here are 10 things you might not have known about these eccentric birds.

1. THE PELICAN FAMILY IS AT LEAST 30 MILLION YEARS OLD.

The earliest pelican fossil on record is a 30-million-year-old skull that was found in the Oligocene deposits of France. Paleontologists have also uncovered younger material from places like Germany, India, Kenya, Peru, Australia, and North Carolina. Today, there are eight living species and you can find some combination of them dwelling on every continent except Antarctica.

The question of where pelicans fit on the avian family tree has been debated for centuries, though genetic evidence now suggests that their closest extant relatives are the bizarre-looking shoebill and a wading bird known as the hamerkop.

2. THEY DON'T STORE FOOD IN THE POUCH ON THEIR BILLS.

The large, fibrous skin pouch that dangles from a pelican's bill is called the gular pouch (or, occasionally, the gular sac). Many people mistakenly believe it’s used to store food, like a built-in lunch box. The idea was popularized by a limerick of unknown authorship:

“A wonderful bird is the pelican.
His beak can hold more than his belly can.
He can hold in his beak enough food for a week.
But I’ll be damned if I can see how the helican."

While the rhyme is amusing, it isn’t accurate. In reality, pelicans use their gular pouches as a means of capturing food—not as a place to keep it tucked away for extended periods. The highly-flexible sacs can expand or contract, and the lower jaw bones they’re connected to are capable of bowing outwards, which enables the birds to use their sacs as fishing nets. Once a pelican captures its prey, the bird drains any water it may have accidentally captured with it by tilting its head and contracting those pouch muscles. (Fun fact: Some species can hold three gallons’ worth of liquid in their gular sacs.) Usually, the prey is swallowed immediately after the water purge.

3. PELICANS DON’T JUST EAT FISH.

In 2006, Londoners were shocked when a pigeon was swallowed whole by a great white pelican in front of some horrified kids at St. James's Park. Attacks like that aren’t unusual: Although pelicans specialize in eating fish, they also prey on crustaceans, amphibians, turtles, and—yes—other birds. If it can fit down their throats, it’s fair game.

4. TWO SPECIES PLUNGE-DIVE FOR FOOD.

The brown pelican is a keen-eyed predator that can spot a fish swimming under the ocean’s surface even while flying 60 feet above. Its bigger cousin, the Peruvian pelican, also has great vision. Once a target has been spotted from above, the pelicans plunge into the sea bill-first at high speeds—and often from a height of several stories. When they collide with the prey, the impact force usually stuns the victim and it’s then scooped up in the gular pouch.

It’s a dangerous stunt, but pelicans have numerous adaptations that keep them from injuring themselves when they smack into the water. To keep their neck vertebrae from getting broken, they stiffen the surrounding muscles as they dive; by throwing their wings straight backwards, pelicans can avoid fracturing any of the bones in the appendages on the unforgiving waves. Air sacs under the skin around their neck and breast area inflate before the bird hits the water’s surface, and the gular pouch behaves like an air bag: the instant a bird’s jaws are thrown open under the water, its forward momentum is slowed. Good form takes practice. Young brown and Peruvian pelicans struggle with their marksmanship at first, but over time, they get better at successfully dive-bombing fish.

5. SOME HUNT IN GROUPS.

Most pelicans don't dive bomb their prey; they scoop it up while treading along on the water’s surface. To increase their chances of success, the birds occasionally form hunting parties, gathering in a U-shape and beating their wings on the water to corral fish into a tight cluster—or drive them into the shallows.

6. THE AMERICAN WHITE PELICAN GROWS A TEMPORARY “HORN.”

An impressive bird indigenous to North America, this pelican stands around 4 feet tall and sports a 9-foot wingspan. Every year, something weird happens to the adults. Breeding season for American white pelicans lasts from late March to early May. When it arrives, a broad, flat, yellow or orange “horn” appears on the upper bills of sexually mature birds (both male and female). At some point in May, the fibrous structures fall off, to be replaced with brand new ones the following season.

7. ALL FOUR OF A PELICAN'S TOES ARE UNITED BY WEBBING.

Water birds tend to have four toes on each foot along with some degree of webbing. But in geese and ducks, the webbing is only present between the three toes that point forward. None is connected to the fourth toe, which—in the aforementioned species—is small and oriented in the opposite direction. Pelicans are different. They have totipalmate feet, which means that on each foot, there’s webbing that connects all four toes. Other birds with this kind of arrangement include cormorants, gannets, and boobies.

8. THEY PLAYED A SURPRISING ROLE IN THE HISTORY OF CHRISTIAN ART.

In medieval Europe, it was believed that whenever food grew scarce, mother pelicans would intentionally stab themselves on the breast with their beaks and then use the blood to feed their chicks. It's a noble idea, but it's a myth that probably has something to do with the gular pouches of Dalmatian pelicans, which turn an orang-reddish color during the breeding season. Maybe an onlooker saw one preening and got the wrong idea. Regardless, the myth of bloodletting pelicans struck a chord with Christian artists, who compared the gesture to the sacrifice Jesus made on humanity’s behalf. Thus, the motif became widespread in Europe during the late medieval and early Renaissance periods. A 1611 edition of the King James Bible featured the image of a breast-piercing pelican. The symbol also appears in a 1575 portrait of Queen Elizabeth I.

9. THEY'RE MOUTH-BREATHERS.

As this video from Ohio University explains, pelicans technically have nasal openings. However, in all eight species, the nostrils are sealed off, buried under the beak’s horny sheath. This doesn’t mean that the cavities are functionless, though: The hidden nostrils house special glands which remove excess salt from the blood stream. Since pelicans and other maritime birds ingest sea water to survive, this trait is a real life-saver. Because their nostrils are walled-off and clogged up by desalinizing glands, it should come as no surprise that pelicans predominantly breathe through their mouths.

10. BROWN PELICANS HAVE MADE A REMARKABLE COMEBACK OVER THE PAST 50 YEARS.

The insecticide known as DDT, which rose to prominence during the 1950s and 1960s, infested whole food chains. After it was sprayed on crops, it was consumed by earthworms, and run-off ensured fish got a dose, too. In turn, these animals were transferring the substance to the various birds that ate them. Although DDT didn’t kill many avians directly, it did have a knack for weakening their egg shells. As a result, the populations of many beloved species—including bald eagles, peregrine falcons, and brown pelicans—took a hit, and the brown pelican all but vanished in vast swaths of the country.

A 1938 census had counted 5000 breeding pairs of brown pelicans in Louisiana. But in 1963, not a single brown pelican sighting was recorded within the state. Texas birders observed similar declines. While early declines were caused by hunters and fishermen, these later declines were pinned on industrial pollutants and insecticides like DDT. Then, a badly-needed break came when public outrage drove the Environmental Protection Agency to ban DDT in 1972. Since that time, the brown pelican has reversed its once-gloomy fortunes. Reintroduction campaigns helped the birds bounce back in Louisiana, Texas, and elsewhere. The brown pelican was listed as endangered in 1970, but in 1985, brown pelicans in a few southern states were removed from the list. Then in 2009, the species was taken off the list entirely.

Why Do Bats Hang Upside Down?

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iStock.com/CraigRJD

Stefan Pociask:

The age-old question of upside down bats. Yes, it is awfully weird that there is an animal—a mammal even—that hangs upside down. Sure, some monkeys do it when they're just monkeying around. And a few other tree climbers, like margays, hang upside down if they are reaching for something or—again, like the margay cat—may actually even hunt that way ... But bats are the only animals that actually spend most of their time hanging upside down: feeding this way, raising their young this way, and, yes, sleeping or roosting this way.

There is actually a very good and sensible reason why they do this: They have to hang upside down so that they can fly.

First off, we have to acknowledge that bats are not birds, nor are they insects. These are the other two animals that have true powered flight (as opposed to gliding). The difference between bat flight and bird or insect flight is weight—specifically, the ratio of weight to lift-capacity of the wings. If you walk up to a bird or insect, most species will be able to fly right up into the air from a motionless position, and do it quickly.

Bats, on the other hand (or, other wing), can’t do that. They have a lot of difficulty taking off from the ground (not that they can’t do it ... it’s just more difficult). Insects and birds often actually jump into the air to give them a start in the right direction, then their powerful wings take them up, up, and away.

Birds have hollow bones; bats don’t. Insects are made of lightweight chitin or soft, light tissue; bats aren’t. And bats don’t have what you could call "powerful" wings. These amazing creatures are mammals, after all. The only flying mammals. Nature found a way to evolve such an unlikely thing as a flying mammal, so some compromises had to be made. Bats, once airborne, manage perfectly well in the air, and can literally fly circles around most birds in flight. The problem is in first getting off the ground.

To compensate for the extra weight that mammals must have, to compensate for the problem of getting off the ground, evolution found another way for bats to transition from being motionless to immediately being able to fly when necessary. Evolution said, “How about if we drop them from above? That way they are immediately in the air, and all they need to do is start flapping."

It was a great idea, as it turns out. Except bat feet aren’t any good for perching on a branch. They are mammals, not birds, so their musculature, their bones, and their tendons are set up in a completely different way. When a bird squats down on a branch, their tendons actually lock their toes into an even tighter grip on the perch. It happens automatically. That’s part of being a bird, and is universal. That’s why they don’t fall off in their sleep.

Bats, as mammals, are set up differently. Therefore, to compensate for that fact, nature said, “How about if we have them hang upside down? That way, their tendons will actually pull their toes closed, just like a bird does from the opposite direction.” So that’s what evolved. Bats hang from the bottom of something, and all they have to do is "let go" and they are instantly flying. In fact, with this gravity-assist method, they can achieve instant flight even faster than birds, who have to work against gravity.

Side note: In case you were wondering how bats poop and pee while upside down ... First off, pooping is no big deal. Bat poop looks like tiny grains of rice; if they are hanging, it just falls to the floor of the bat cave as guano. Pee, however ... well, they have that covered too. They just “hold it” until they are flying.

So there you go. Bats sleep hanging upside down because they are mammals and can’t take off into the air like birds can (at least not without difficulty). But, if they're hanging, all they do is let go.

Makes total sense, right?

Now, having said all that about upside down bats, I must mention the following: Not all of the 1240-plus species of bats do hang upside down. There are exceptions—about six of them, within two different families. One is in South America (Thyropteridae) and the other is in Madagascar (Myzopodidae). The Myzopodidae, which includes just one species, is exceedingly rare.

So it turns out that these bats roost inside the tubes of young, unfurled banana leaves and other similar large leaves. When they attach themselves to the inside of this rolled leaf, they do it head-up. The problem with living inside of rolled-up leaves is that within a few days, these leaves will continue growing, and eventually open up. Whenever that happens, the whole group of bats has to pick up and move to another home. Over and over again. All six of these species of rare bats have a suction cup on each wrist and ankle, and they use these to attach to the smooth surface of the inside of the leaf tube. Evolution: the more you learn, the more amazing it becomes.

This post originally appeared on Quora. Click here to view.

Sorry, But Last Month's Polar Vortex Didn't Wipe Out 95 Percent of Stink Bugs

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iStock.com/drnadig

In the wake of the polar vortex that brought bone-chilling temperatures to the Midwest and Northeast U.S. last month, a silver lining appeared to emerge. Multiple media outlets recently reported that the weather phenomenon may have wiped out as many as 95 percent of brown marmorated stink bugs in areas that weren't accustomed to such frigid conditions.

Unless you like having your home smell like the musky, burnt-cilantro scent of squished stink bugs, we have some bad news: Those reports are not entirely accurate. According to KDKA Radio in Pittsburgh, the Virginia Tech lab experiment that has been widely cited in these articles is a little outdated, having been conducted in 2014.

At the time, it appeared to be a promising find. Researchers from the university had collected stink bugs, placed them in insulated buckets, and waited to see if they'd survive a particularly cold spell. Even though the insects were in a dormant state called diapause, 95 percent of them died when a polar vortex hit the region. That led entomology professor Thomas Kuhar to tell The Washington Post in 2014 that “there should be significant mortality of BMSB (brown marmorated stink bugs) and many other overwinter insects this year."

However, in an email to Mental Floss, Kuhar says the rehashing of "some media misquotes from 2014" led to these too-good-to-be-true reports being recirculated this week. "There is no new research on this topic," he writes. Furthermore, the lab experiment can't easily be applied to real-life scenarios because stink bugs tend to seek shelter during the winter. "Severe sub-freezing temperatures will negatively impact winter survival of these stink bugs if they were unable to find suitable shelter such as inside of houses and sheds," he writes.

These sentiments were echoed by entomologist Chad Gore of Ehrlich Pest Control, who spoke with KDKA Radio. "When they can find that shelter, they can survive the winter. Those that are exposed, they will freeze and we won’t have to worry about them," he said.

But is there still a chance we will see fewer stink bugs in the spring? Gore says don't count on it. "I’d love to be able to reassure everybody and say that 95 percent of all of our stink bugs are going to be gone, but that’s just not going to be the case," he said. "We’re still going to see them."

Even though stink bugs don't bite and are basically harmless (though they sometimes trigger allergic reactions), they can be difficult to trap once they've found a way into one's house. The invasive species is also harmful to crops—especially grapes—and sometimes end up getting pulverized and fermented in red wine. Suffice it to say, a lot of people would be happy if the pests suddenly disappeared. For now, though, we'll have to keep on dreaming.

[h/t KDKA Radio]

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