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.

Chimpanzees Bond by Watching Movies Together, Too

Windzepher/iStock via Getty Images
Windzepher/iStock via Getty Images

Scientists at the Wolfgang Kohler Primate Research Center in Germany recently discovered that, like humans, chimpanzees bond when they watch movies together, the BBC reports.

In the study, published in Proceedings of the Royal Society B, researchers stationed pairs of chimpanzees in front of screens that showed a video of a family of chimps playing with a young chimp. They found that afterward, the chimps would spend more time grooming and interacting with each other—or simply being in the same part of the room—than they would without having watched the video.

They gave the chimps fruit juice to keep them calm and occupied while they viewed the video, and they chose a subject that chimps have previously proven to be most interested in: other chimps. They also used eye trackers to ensure the chimps were actually watching the video. If you’ve ever watched a movie with friends, you might notice similarities between the chimps’ experience and your own. Drinks (and snacks) also keep us calm and occupied while we watch, and we like to watch movies about other humans. Since this study only showed that chimps bond over programs about their own species, we don’t know if it would work the same way if they watched something completely unrelated to them, like humans do—say, The Lion King.

Bonding through shared experiences was thought to be one of the traits that make us uniquely human, and some researchers have argued that other species don’t have the psychological mechanisms to realize that they’re even sharing an experience with another. This study suggests that social activities for apes don’t just serve utilitarian purposes like traveling together for safety, and that they’re capable of a more human-like social closeness.

The part that is uniquely human about this study is the fact that they were studying the effect of a screen, as opposed to something less man-made. The chimps in question have participated in other studies, so they may be more accustomed to that technology than wild apes. But the study demonstrates that we’re not the only species capable of social interaction for the sake of social interaction.

[h/t BBC]

10 Facts You Should Know About Mosquitoes

tskstock/iStock via Getty Images
tskstock/iStock via Getty Images

Between the itching and the welts and the fears of mosquito-borne viruses, it's easy to forget that mosquitoes are a wonder of evolution, and that maybe they don't get a fair shake from us. Of more than 3000 known species, only 80 actually bite people, and at least one eats other mosquitoes for us. They grow from egg to adult in just five days, begin mating within minutes of hatching, and possess, by way of their stinging mouthparts, some of the coolest appendages in the animal kingdom.

1. Mosquitoes are excellent flyers in bad weather.

The average raindrop is 50 times heavier than the average mosquito, yet they buzz around in the rain with no problems. If a Boeing 747 got whacked with a similarly scaled-up raindrop, there would be 2375 tons of water coming down on it, and things probably wouldn’t turn out as well as they do for the mosquito. How do the insects do it?

A common urban legend said that the bugs were nimble enough to dodge the drops. A few years ago, a team of engineers from the Georgia Institute of Technology watched real mosquitoes and Styrofoam dummy mosquitoes with a high-speed camera during a rainy flight to see if that’s what was really happening. They found that the bugs don’t fly fast enough to dodge the drops, but their slowness is what keeps them from getting knocked out of the sky. A mosquito’s low mass even at slow speed doesn’t provide enough of a target for a raindrop to splash on collision. Instead, the drop just deforms, and doesn’t transfer enough momentum to the mosquito to disrupt its flight.

2. Texas is the mosquito capital of America.

Of the 3000 species of mosquitoes around the world, at least 150 are found in the United States, and 85 of those call Texas home. When people say everything's bigger in Texas, you can also include the biodiversity of the state's biting, disease-carrying insects.

3. Some mosquitoes are truly dangerous to humans ...

The female mosquito, which is the one that stings and sucks blood, is an incredible transmitter of disease and, because of that, the deadliest animal in the world. Each year, the malaria parasites they transmit kill 2 million to 3 million people and infect another 200 million or more. They also spread pathogens that cause yellow fever, dengue fever, Rift Valley fever, Chikungunya and West Nile disease.

4. ... and some mosquitoes are harmless.

Not every species of mosquito sucks blood from people, and among those that do, not every one transmits disease. The blood suckers don’t even need to bite you for every meal. Males live entirely on nectar and other plant fluids, and the females’ diet is primarily plant-based, too. Most of the time, they only go after people when they’re ready to reproduce, because blood contains lipids, proteins, and other nutrients needed for the production of eggs.

5. MosquitoEs actually help the environment.

When you’re rubbing calamine lotion all over yourself, mosquitoes might not seem to serve any purpose but to annoy you, but many species play important ecological roles. The mosquitoes Aedes impiger and Aedes nigripes, which gather in thick clouds in Arctic Russia and Canada, are an important food source for migrating birds. Farther south, birds, insects, spiders, salamanders, lizards, frogs, and fish also eat different mosquito species regularly. Plants need them, too, and some, like the blunt-leaved orchid and endangered monkeyface orchid, rely on mosquitoes as their primary pollinator.

Some mosquito species are also excellent at mosquito control. Species of the genus Toxorhynchites feed on the larvae and immature stages of other mosquitoes and will sometimes even cannibalize members of their own species.

6. Mosquitoes are amazing hunters (as if we needed to tell you that).

Mosquitoes are adept at picking up on the chemicals given off by their human hosts. They can detect the carbon dioxide in our breath, the 1-octen-3-ol in our breath and sweat, and other organic substances we produce with the 70-plus types of odor and chemical receptors in their antennae. These receptors can pick up traces of chemicals from hundreds of feet away, and once the mosquito closes in, it tracks its meal chemically and also visually—and they’re fond of people wearing dark colors.

7. Mosquitoes can be picky.

If it seems like you’re always covered head to toe by bites while people who were sitting right next to you only have one or two, it’s not just paranoia; the skeeters actually are out to get you. Some people happen to give off more of the odors and compounds that mosquitoes find simply irresistible, while others emit less of those and more of the compounds that make them unattractive to mosquitoes—either by acting as repellents or by masking the compounds that mosquitoes would find attractive.

8. A female mosquito's mouth is primed for sucking blood.

A mosquito doesn’t simply sink its proboscis into your skin and start sucking. What you see sticking out of a mosquito’s face is the labium, which sheaths the mouthparts that really do all the work. The labium bends back when a mosquito bites, allowing these other parts to pass through its tip and do their thing. The sharp, pointed mandibles and maxillae, which both come in pairs, are used to pierce the skin, and the hollow hypopharynx and the labrum are used to deliver saliva and draw blood, respectively.

9. Mosquito saliva prevents blood clotting.

The saliva that gets pumped out from the hypopharynx during a bite is necessary to get around our blood’s tendency to clot. It contains a grab bag of chemicals that suppress vascular constriction, blood clotting and platelet aggregation, keeping our blood from clogging up the mosquitoes' labrum and ruining their meal.

10. Mosquitoes can explode.

Blood pressure makes a mosquito's meal easier by helping to fill its stomach faster, but urban legend says it can also lead to their doom. Story goes, you can flex a muscle close to the bite site or stretch your skin taut so the mosquito can’t pull out its proboscis and your blood pressure will fill the bug until it bursts. The consensus among entomologists seems to be that this is bunk, but there is a more complicated way of blowing the bugs up. To make a blood bomb, you’ve got to sever the mosquito’s ventral nerve cord, which transmits information about satiety. When it's cut, the cord can’t tell the mosquito’s brain that its stomach is full, so it’ll keep feeding until it reaches critical mass. At least one researcher found that mosquitoes clueless about how full they were would keep sucking even after their guts had exploded, sending showers of blood spilling out of their blown-out back end.

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