Messing with Mother Nature: 5 Invasion Stories

Introduction of non-native species to a new environment is often done completely by accident. Anywhere people travel, something unseen can be traveling along, too. Planes, ships, and other methods of distant travel have taken critters to places they don't belong, and we only discover the problems they cause much later.

1. Snakes on Guam

Sometime between 1945 and 1952, the brown tree snake (Boiga irregularis) was introduced to the island of Guam, where it had never lived before. There may have been several instances of snakes stowing away on cargo ships, as Guam is a major transit point. Snakes flourished on Guam, where there was plenty of food available in the form of birds, bats, and lizards. By 1990, almost all the native birds were gone, and plans were developed to battle the snakes with multiple weapons: poison, fumigation, barriers, trapping, habitat modification, and port detection with dogs. But the snake damage continued. Since they had eaten all the birds and most of the fruit bats, pollination of native plants and trees suffered. In 2010, a new plan began: a government conservation team stuffed the carcasses of dead mice with Tylenol and airlifted them over the forests of Guam. A brown tree snake is one of the few snake species that will eat an animal it hasn't killed, and a small dose of acetaminophen is deadly to them. The "mice bombs" were attached to pieces of cardboard and paper streamers, so they would be caught in tree limbs where the snakes reside. The effectiveness of this plan has not yet been publicized, but scientists don't expect it to wipe out the snakes; they just hope to control their numbers. Photograph by Flicker user Armed Forces Pest Management Board.

2. Kudzu Bugs

The Side

Kudzu is an invasive vine that was imported from Japan in the 19th century as cattle feed, to use for erosion control, and as an ornamental plant. It is native to China, where the environment controls its spread. However, in the U.S. it flourished wildly and now covers the South. In 2009, an Asian insect called Megacopta cribraria reached the U.S., possibly by plane, and thrived by eating kudzu. You would think that a biological control of the weed would be welcomed, but there are other consequences to consider. The kudzu bug spread through several southern states, and is eating soybeans and bean crops as well as kudzu, which gave the bugs the name Bean Plataspid. They also invade homes and smell really bad, which is why they are also called Globular Stink bugs. Photograph by Flickr user Charles Lam.

3. The Catalina Island Bison

Catalina Buffalo

Santa Catalina Island is a few miles off the coast of Los Angeles. In 1924, a film crew shot a Zane Grey movie there called The Vanishing American, and brought 14 head of bison with them. The animals never showed up in the finished film, however. The story goes that the film crew left the bison behind after filming in order to save the money it would cost to transport them. By 1969, there were 400 bison on Catalina Island, and they were eating up the native plants. The Catalina Island Conservancy has employed various methods to control the size of the herd. A number of bison have been shipped out over the years: at first they were sold, then many were relocated to the Great Plains in multiple shipments. In the past few years, the Conservancy has turned to birth control methods, which appear to work and are much cheaper and less stressful than relocating the large animals. The Conservancy is also working to save the Catalina Island fox, which is a native species, and control invasive plants. Photograph by Flickr user Kenneth Hagemeyer.

4. Mussels in Michigan

A shotgun shell

Zebra mussels and Quagga mussels are both invasive species which arrived in the Great Lakes by attaching themselves to ships. Zebra mussels are native to the Caspian Sea and were first spotted near Detroit in 1988. You can follow the spread of Zebra mussels by running your mouse over the dates on this map. The Quagga mussel is native to the Dneiper River area of Ukraine, but has also invaded the Great Lakes and other areas of the U.S. Both species are upsetting the Great Lakes ecosystem:

These mussels have permanently changed the ecosystem. Before the mussels invaded, Lake Michigan water was mostly cloudy and millions of tiny microorganisms provided a food base for fish. Because the mussels filter the microorganisms, the waters today are surprisingly clear, allowing light to penetrate to greater depths, which in turn promotes prolific, nuisance algae blooms.

The mussels are also thought to be one of the main reasons that the population of the crustacean Diporeia, a major food source for fish, is declining rapidly, although industrial pollutants may also be a factor. Zebra mussel shells photographed by Flickr user Benny Mazur.

5. Farmed Algae Eaten by Shrimp

More Copepods

In order to curb global warming, there have been several projects to dump iron dust into the sea in order to encourage algae growth, because plankton absorbs carbon dioxide (CO2), a greenhouse gas. However, the location of these dumps makes a big difference. In 2009, ten tons of ferrous sulphate were pumped into the waters off Argentina. The algae bloomed, alright, but it was not the species that was expected. The project hoped to encourage growth of large diatom algae, but instead, tiny haptophytes gobbled up the iron. Haptophytes are the preferred prey of copepods, which are small shrimp-like animals. In this instance, the experiment was a failure and the iron was a loss, but scientists think that that the explosion of copepods will do no harm to the environment. They think. Copepod photograph by Flickr user Labut.

See also: Messing with Mother Nature: 5 Cautionary Tales, Messing with Mother Nature: Snakeheads, and Messing with Mother Nature: The Macquarie Island Ecosystem.

Wolfgang via Flickr // CC BY-ND 2.0
8 Legendary Monsters of Christmas
Wolfgang via Flickr // CC BY-ND 2.0
Wolfgang via Flickr // CC BY-ND 2.0

The customs of the holiday season, which include St. Nicholas Day, New Years Day, and Epiphany, as well as Christmas, often incorporate earlier pagan traditions that have been appropriated and adapted for contemporary use. Customs that encourage little children to be good so as to deserve their Christmas gifts often come with a dark side: the punishment you'll receive from a monster or evil being of some sort if you aren't good! These nefarious characters vary from place to place, and they go by many different names and images.


As a tool to encourage good behavior in children, Santa serves as the carrot, and Krampus is the stick. Krampus is the evil demon anti-Santa, or maybe his evil twin. Krampus Night is celebrated on December 5, the eve of St. Nicholas Day in Austria and other parts of Europe. Public celebrations that night have many Krampuses walking the streets, looking for people to beat. Alcohol is also involved. Injuries in recent years have led to some reforms, such as requiring all Krampuses to wear numbers so they may identified in case of overly violent behavior.

Krampus may look like a devil, or like a wild alpine beast, depending on what materials are available to make a Krampus costume. In modern times, people can spend as much as they like to become the best Krampus around—and the tradition is spreading beyond Europe. Many cities in America have their own Krampus Nights now.


Jólakötturinn is the Icelandic Yule Cat or Christmas Cat. He is not a nice cat. In fact, he might eat you. This character is tied to an Icelandic tradition in which those who finished all their work on time received new clothes for Christmas, while those who were lazy did not (although this is mainly a threat). To encourage children to work hard, parents told the tale of the Yule Cat, saying that Jólakötturinn could tell who the lazy children were because they did not have at least one new item of clothing for Christmas—and these children would be sacrificed to the Yule Cat. This reminder tends to spur children into doing their chores! A poem written about the cat ends with a suggestion that children help out the needy, so they, too, can have the protection of new clothing. It's no wonder that Icelanders put in more overtime at work than most Europeans.


Flickr // Markus Ortner

Tales told in Germany and Austria sometimes feature a witch named Frau Perchta who hands out both rewards and punishments during the 12 days of Christmas (December 25 through Epiphany on January 6). She is best known for her gruesome punishment of the sinful: She will rip out your internal organs and replace them with garbage. The ugly image of Perchta may show up in Christmas processions in Austria, somewhat like Krampus.

Perchta's story is thought to have descended from a legendary Alpine goddess of nature, who tends the forest most of the year and deals with humans only during Christmas. In modern celebrations, Perchta or a close relation may show up in processions during Fastnacht, the Alpine festival just before Lent. There may be some connection between Frau Perchta and the Italian witch La Befana, but La Befana isn't really a monster: she's an ugly but good witch who leaves presents.


A drawing of Belsnickel.
Lucas, Flickr // CC BY 2.0

Belsnickel is a male character from southwestern German lore who traveled to the United States and survives in Pennsylvania Dutch customs. He comes to children sometime before Christmas, wearing tattered old clothing and raggedy fur. Belsnickel carries a switch to frighten children and candy to reward them for good behavior. In modern visits, the switch is only used for noise, and to warn children they still have time to be good before Christmas. Then all the children get candy, if they are polite about it. The name Belsnickel is a portmanteau of the German belzen (meaning to wallop) and nickel for St. Nicholas. See a video of a Belsnickel visit here.

Knecht Ruprecht and Ru Klaas are similar characters from German folklore who dole out beatings to bad children, leaving St. Nicholas to reward good children with gifts.


Hans Trapp is another "anti-Santa" who hands out punishment to bad children in the Alsace and Lorraine regions of France. The legend says that Trapp was a real man, a rich, greedy, and evil man, who worshiped Satan and was excommunicated from the Catholic Church. He was exiled into the forest where he preyed upon children, disguised as a scarecrow with straw jutting out from his clothing. He was about to eat one boy he captured when he was struck by lightning and killed—a punishment of his own from God. Still, he visits young children before Christmas, dressed as a scarecrow, to scare them into good behavior.


The French legend of Père Fouettard, whose name translates to "Father Whipper," begins with an evil butcher who craved children to eat. He (or his wife) lured three boys into his butcher shop, where he killed, chopped, and salted them. St. Nicholas came to the rescue, resurrected the boys, and took custody of the butcher. The captive butcher became Père Fouettard, St. Nicholas' servant whose job it is to dispense punishment to bad children on St. Nicholas Day.


The Jólasveinar, or Yule Lads, are 13 Icelandic trolls, who each have a name and distinct personality. In ancient times, they stole things and caused trouble around Christmastime, so they were used to scare children into behaving, like the Yule Cat. However, the 20th century brought tales of the benevolent Norwegian figure Julenisse (Santa Claus), who brought gifts to good children. The traditions became mingled, until the formerly devilish Jólasveinar became kind enough to leave gifts in shoes that children leave out ... if they are good boys and girls. 


All the Yule Lads answer to Grýla, their mother. She predates the Yule Lads in Icelandic legend as the ogress who kidnaps, cooks, and eats children who don't obey their parents. She only became associated with Christmas in the 17th century, when she was assigned to be the mother of the Yule Lads. According to legend, Grýla had three different husbands and 72 children, all who caused trouble ranging from harmless mischief to murder. As if the household wasn't crowded enough, the Yule Cat also lives with Grýla. This ogress is so much of a troublemaker that The Onion blamed her for the 2010 eruption of the Eyjafjallajökull volcano.

A version of this post originally ran in 2013. See also: more Legendary Monsters

Keystone/Getty Images
84 Years Ago Today: Goodbye Prohibition!
A huge queue outside the Board of Health offices in Centre Street, New York, for licenses to sell alcohol shortly after the repeal of prohibition. The repeal of prohibition was a key policy of Franklin Roosevelt's government as it allowed the government an opportunity to raise tax revenues at a time of economic hardship.
A huge queue outside the Board of Health offices in Centre Street, New York, for licenses to sell alcohol shortly after the repeal of prohibition. The repeal of prohibition was a key policy of Franklin Roosevelt's government as it allowed the government an opportunity to raise tax revenues at a time of economic hardship.
Keystone/Getty Images

It was 84 years ago today that the Twenty-First Amendment to the Constitution was ratified, repealing the earlier Amendment that declared the manufacture, sale, and transport of alcohol illegal in the United States. Prohibition was over! Booze that had been illegal for 13 years was suddenly legal again, and our long national nightmare was finally over.

A giant barrel of beer, part of a demonstration against prohibition in America.
Henry Guttmann/Getty Images

Prohibition of alcohol was not a popular doctrine. It turned formerly law-abiding citizens into criminals. It overwhelmed police with enforcement duties and gave rise to organized crime. In cities like Milwaukee and St. Louis, the dismantling of breweries left thousands of people unemployed.

Photograph courtesy of the Boston Public Library

Homemade alcohol was often dangerous and some people died from drinking it. Some turned to Sterno or industrial alcohol, which was dangerous and sometimes poisoned by the government to discourage drinking. State and federal governments were spending a lot of money on enforcement, while missing out on taxes from alcohol.

New York City Deputy Police Commissioner John A. Leach (right) watches agents pour liquor into sewer following a raid during the height of Prohibition.

The midterm elections of 1930 saw the majority in Congress switch from Republican to Democratic, signaling a shift in public opinion about Prohibition as well as concerns about the depressed economy. Franklin Roosevelt, who urged repeal, was elected president in 1932. The Twenty-first Amendment to the Constitution was proposed by Congress in February of 1933, the sole purpose of which was to repeal the Eighteenth Amendment establishing Prohibition.

American men guarding their private beer brewing hide-out, during Prohibition.
Keystone/Getty Images

With passage of the Constitutional Amendment to repeal Prohibition a foregone conclusion, a huge number of businessmen lined up at the Board of Health offices in New York in April of 1933 to apply for liquor licenses to be issued as soon as the repeal was ratified.

The Amendment was ratified by the states by the mechanism of special state ratifying conventions instead of state legislatures. Many states ratified the repeal as soon as conventions could be organized. The ratifications by the required two-thirds of the states was achieved on December 5, 1933, when conventions in Ohio, Pennsylvania, and Utah agreed to repeal Prohibition through the Amendment.

Workmen unloading crates of beer stacked at a New York brewery shortly after the repeal of Prohibition.
Keystone/Getty Images

A brewery warehouse in New York stacked crates past the ceiling to satisfy a thirsty nation after the repeal of Prohibition.

Keystone/Getty Images

Liquor wouldn't officially be legal until December 15th, but Americans celebrated openly anyway, and in most places, law enforcement officials let them.


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