8 Terrifying Animal Swarms Created by Human Stupidity

But if you do know something about starlings, you know they're considered a nuisance because of their habit of roosting in flocks of several million, and then tearing through crops like locusts. The starling is one of the most deeply resented birds in the avian community.

"MY GOD ... WHAT HAVE WE DONE?"

The released birds went on to reproduce like mad, increasing their numbers to somewhere around 200 million. By all accounts, starlings are natural terrors. They will force other birds out of their nests and eat their eggs. They swarm in those massive flocks, just eating absolutely everything they can fit in their beaks, stealing food from other species and wreaking havoc on agriculture.

And God help you if you have food left out in the open -- one feedlot in the U.S. had over 200,000 starlings lining almost every spare surface at one time, leading us to wonder why the National Guard wasn't contacted.

In 1960, a Lockheed Electra crashed into Boston Harbor seconds after takeoff when 20,000 starlings flew into its engine, killing 62 people on board and proving that the starling's lust for seed is matched only by its thirst for blood.

Thanks, Shakespeare.

Think about your bedroom. It's about, what, 10 feet across? The yellow crazy ant is taking over that much land, each day, every day.

The crazy ant lives up to its name because of its tendency to shake and twitch like a mental patient, and also for its strange habit of collecting tin cans in a shopping cart and yelling at random people on the street . One day some of the ants managed to stow away on some trucks and wound up on Christmas Island. They multiplied, and multiplied, and are currently spreading at a rate of three meters per day.

Strangely, Christmas Island was already famous for being home to millions of aptly named Christmas Island red crabs, who once a year migrate across the island in groups of several million.

So that means the island is now known specifically for being full of tiny creatures with lots of legs that you want to kill with a hammer.

"MY GOD ... WHAT HAVE WE DONE?"

Those first ants that crawled off the trucks went on to form several super colonies on the island, creating the greatest concentration of ants ever recorded anywhere on Earth. Over 30 percent of Christmas Island now belongs to the ants.

And when we say "belongs to the ants" we mean it in the most absolute terms. They're so overwhelming and ravenous that no other living creatures are able to survive in areas that have been infected by the ants, literally leaving them devoid of any other life.

As you can imagine, the ants are utterly devastating to the environment, eating the crabs and becoming bigger and stronger in the process.

That's the difference between the mass of migrating crabs the island is used to and this infestation of ants; the crabs actually don't harm anyone and take over the island for only a few weeks of the year. The ants are slowly and methodically taking over the entire land mass and will never leave, ever.

The crabs also used to spread seeds with their burrowing, but the ants have put a stop to that, dramatically affecting the way the forests are growing and will continue to grow. The ants might as well carry flamethrowers and drive bulldozers.

Not that crabs can't do their share of damage ...

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Thus the Soviet Union introduced the Red King Crab into Russian waters in the 1960s. Crab for everyone!

"MY GOD ... WHAT HAVE WE DONE?"

Red crabs 1) travel in huge, dense packs and 2) are extremely voracious eaters -- they will literally eat everything. So they essentially form one huge, living vacuum cleaner, sucking up so much plankton, fish eggs, fish, mussels, clams, starfish, kelp, barnacles and the like that the areas they pass through are left as barren underwater deserts.

It doesn't help that these guys spread and reproduce at alarming rates. In 20 years, their population went zero to 20 million in the Barents Sea off the coast of northern Russia. They're even starting to invade Norwegian waters in what is essentially a charge of communist crustaceans.

They may be a boon to the new crab fishermen in Norway and Russia, but for the rest of the fishermen, they are the devil incarnate. The crabs not only eat all the things the fishermen are trying to catch but also rip apart fishing nets, eat bait off hooks and generally wave their armored balls in everyone's faces.

For some inexplicable reason, however, the crabs are protected through a diplomatic accord by Norway and Russia, basically making them Lethal Weapon 2 villains with shells.

Related: Apparently, Different Animals Keep Evolving Into Crabs

"MY GOD ... WHAT HAVE WE DONE?"

Rabbits are Australia's No. 1 cause of plant and animal extinction, literally starving other species to death and eating plants into oblivion. They're also one of the leading causes of soil erosion and crop destruction, costing the continent around $600 million in losses per year and scorching the Earth behind them.

As a result of the rabbit epidemic, Australia now has a pretty strict customs program, by which we mean nothing gets in or out of Australia, ever. You can't even bring in the peanuts you got on the flight over, even though we're pretty sure peanuts haven't brought about any extinction-level events.

At some point during World War II, a cargo ship pulled up to the Pacific island of Guam and, unnoticed by anyone, out slithered a brown tree snake that had been hiding on board.

Well, can't be that big of a deal -- originating from Australia, the brown tree snake poses almost no threat to an adult human and probably spends most of its time being picked on by all the other snakes.

"MY GOD... WHAT HAVE WE DONE?"

Since Guam has no indigenous species of snakes, the few brown tree snakes that sneaked onto the island were 1) able to breed out of control and 2) able to catch just about every native creature off-guard and eat the shit out of them. Birds, lizards, rodents -- scientists have concluded that the snake is responsible for decimating the populations of several species and even bringing others to extinction. There are currently millions of snakes in Guam today, so the small-animal genocide is likely to continue for some years to come.

Oh, and the snakes have also been known to cause rolling blackouts and power outages by climbing into power boxes and shorting them out, presumably turning the snakes into creatures of pure energy like that one gremlin in Gremlins 2.

Related: Massive Snake Spotted in Frick Park

Lake Victoria in Africa, meanwhile, was at one time considered the most diverse fishing environment on the entire planet. But damn it, there was one monstrous fish that was clearly missing from the collection. Thus the giant and terrifying Nile perch was introduced to the lake to try to attract more sport fishermen to the area and generate some revenue, because old drunk white people mean nothing but dollar signs.

"MY GOD ... WHAT HAVE WE DONE?"

The locals are in fact catching and eating the perch, but the damn things are so big they're actually contributing to deforestation in the area because of the massive amount of wood required to cook them.

And in the meantime, Lake Victoria lost its "most diverse" status after the Nile perch ate just about all of the other fish living in it. In fact, the perch have eaten so many of the lake's indigenous fish that they have had to start eating each other to survive.

Now we can't blame people for wanting to bring tourism and money into the area, but if you want to attract fishermen, perhaps advertising the fact that you have one of the best fishing areas in the world is a decent way to do so without the hassle of introducing giant shark-size monsters into your lake.

The only thing that could make them worse is if they, oh, we don't know, could escape the water. You know, like ...

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The snakehead fish is (you guessed it) a fish with the head of a snake that can grow to be over three feet long and HOLY SHIT LOOK AT IT:

They are normally found horrifying the rivers of Asia and Africa, but they've been springing up in the U.K., Canada and the U.S. The snakehead fish are spread by pet owners who just get tired of taking care of them and dump them into the nearest body of water, except in places like Taiwan and Japan, where they have actually been introduced on purpose to help the fishing industry.

"MY GOD ... WHAT HAVE WE DONE?"

The fish are extremely aggressive and will eat just about anything they can, including other fish, frogs, crayfish, plankton ...

... and rats. And birds. Things that don't live in the water.

Yes, the snakehead fish can freaking walk on land, where it can survive for up to four days and travel a quarter of a mile to other bodies of water. They can do this because they actually have primitive lungs right above their gills that allow them to breathe air. We figure it's only a matter of time before they start boosting cars and robbing convenience stores.

Related: The Vampire Parasite That Replaces A Fish's Tongue

Normally annoying people and sanitary departments alike in the U.S., the raccoon has invaded Europe and Japan thanks to Nazis and anime.

In Europe, the raccoon plague started when the Nazis' Reich Forestry Service decided that it would "enrich the fauna" by introducing raccoons into the German wilderness, a move bewildering to even the most steadfast Nazi supporter. Raccoons were also kept in fur farms in the German countryside.

As for Japan, it all started with a popular anime show in the 1970s called Rascal the Raccoon. As a result of the show, Japanese kids brought in raccoons as pets at the rate of about 1,500 per year. Most of these pets either escaped or were tossed out by their owners, because a raccoon is kind of a pain in the ass to keep indoors.

"MY GOD ... WHAT HAVE WE DONE?"

As you should've learned by now, introducing a nonindigenous animal into an ecosystem can have terrible results. The raccoons caused staggering agricultural losses with their insatiable appetites. In fact, at one point they had pretty much wiped out the German winemaking industry by eating the harvests of numerous vineyards. They've even been known to damage UNESCO World Heritage temples in Japan.

Germany has declared raccoons to be a game animal and encourages people to hunt them, while Japan has made it illegal to import them or to keep any as pets.

Karl Smallwood and Danny Vittore are both freelance writers. You can follow Danny on Twitter here.

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For more ways we've boned up with Mother Nature, check out 6 Animals Humans Accidentally Made Way Scarier and 6 Natural Disasters That Were Caused by Human Stupidity.

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