Overrun by Alien Species

From Japanese knotweed to cane toads, humans have introduced invasive species to new environments with disastrous results

Ever since Neolithic people wandered the earth, inadvertently bringing the mouse along for the ride, humans have been responsible for introducing animal and plant species into new environments. But problems can arise when a non-native species encounters no barriers to population growth, allowing it to rampage unchecked through the new habitat, overwhelming the ecosystem. On more than one occasion, humans have transplanted a species for what seemed like good reasons, only to find out too late that the consequences were disastrous.

One of the most famous examples is celebrating its 150th anniversary this year: the introduction of Japanese knotweed to the U.S. A highly aggressive plant, it can grow 15 feet high and has roots that spread up to 45 feet. Knotweed had already been a hit in Europe because of its pretty little white flowers, and, yes, its miraculous indestructibility.

First mentioned in botanical articles in 1868, knotweed was brought to New York by the Hogg brothers, James and Thomas, eminent American horticulturalists and among the earliest collectors of Japanese plants. Thanks to their extensive contacts, knotweed found a home in arboretums, botanical gardens and even Central Park. Not content with importing one of world’s most invasive shrubs, the Hoggs also introduced Americans to the wonders of kudzu, a dense vine that can grow a foot a day.

Impressed by the vigor of kudzu, agriculturalists recommended using these plants to provide animal fodder and prevent soil erosion. In the 1930s, the government was even paying Southern farmers $8 per acre to plant kudzu. Today it is known as the “vine that ate the South,” because of the way it covers huge tracts of land in a green blanket of death. And Japanese knotweed is still spreading, colonizing entire habitats from Mississippi to Alaska, where only the Arctic tundra holds it back from world domination.

Knotweed has also reached Australia, a country that has been ground zero for the worst excesses of invasive species. In the 19th century, the British imported non-native animals such as rabbits, cats, goats, donkeys, pigs, foxes and camels, causing mass extinctions of Australia’s native mammal species. Australians are still paying the price; there are more rabbits in the country today than wombats, more camels than kangaroos.

Yet the lesson wasn’t learned. In the 1930s, scientists in both Australia and the U.S. decided to import the South American cane toad as a form of biowarfare against beetles that eat sugar cane. The experiment failed, and it turned out that the cane toad was poisonous to any predator that ate it. There’s also the matter of the 30,000 eggs it can lay at a time. Today, the cane toad can be found all over northern Australia and south Florida.

So is there anything we can do once an invasive species has taken up residence? The answer is yes, but it requires more than just fences, traps and pesticides; it means changing human incentives. Today, for instance, the voracious Indo-Pacific lionfish is gobbling up local fish in the west Atlantic, while the Asian carp threatens the ecosystem of the Great Lakes. There is only one solution: We must eat them, dear reader. These invasive fish can be grilled, fried or consumed as sashimi, and they taste delicious. Likewise, kudzu makes great salsa, and Japanese knotweed can be treated like rhubarb. Eat for America and save the environment.

WSJ Historically Speaking: Poison and Politics

From ‘cantarella’ to polonium, governments have used toxins to terrorize and kill their enemies

ILLUSTRATION: THOMAS FUCHS

Among the pallbearers at Senator John McCain’s funeral in Washington last weekend was the Russian dissident Vladimir Kara-Murza. Mr. Kara-Murza is a survivor of two poisoning attempts, in 2015 and 2017, which he believes were intended as retaliation for his activism against the Putin regime.

Indeed, Russia is known or suspected to be responsible for several notorious recent poisoning cases, including the attempted murder this past March of Sergei Skripal, a former Russian spy living in Britain, and his daughter Yulia with the nerve agent Novichok. They survived the attack, but several months later a British woman died of Novichok exposure a few miles from where the Skirpals lived.

Poison has long been a favorite tool of brutal statecraft: It both terrorizes and kills, and it can be administered without detection. The Arthashastra, an ancient Indian political treatise that out-Machiavels Machiavelli, contains hundreds of recipes for toxins, as well as advice on when and how to use them to eliminate an enemy.

Most royal and imperial courts of the classical world were also awash with poison. Though it is impossible to prove so many centuries later, the long list of putative victims includes Alexander the Great (poisoned wine), Emperor Augustus (poisoned figs) and Emperor Claudius (poisoned mushrooms), as well as dozens of royal heirs, relatives, rivals and politicians. King Mithridates of Pontus, an ancient Hellenistic empire, was so paranoid—having survived a poison attempt by his own mother—that he took daily microdoses of every known toxin in order to build up his immunity.

Poisoning reached its next peak during the Italian Renaissance. Every ruling family, from the Medicis to the Viscontis, either fell victim to poison or employed it as a political weapon. The Borgias were even reputed to have their own secret recipe, a variation of arsenic called “cantarella.” Although a large number of their rivals conveniently dropped dead, the Borgias were small fry compared with the republic of Venice. The records of the Venetian Council of Ten reveal that a secret poison program went on for decades. Remarkably, two victims are known to have survived their assassination attempts: Count Francesco Sforza in 1450 and the Ottoman Sultan Mehmed II in 1477.

In the 20th century, the first country known to have established a targeted poisoning program was Russia under the Bolsheviks. According to Boris Volodarsky, a former Russian agent, Lenin ordered the creation of a poison laboratory called the “Special Room” in 1921. By the Cold War, the one-room lab had evolved into an international factory system staffed by hundreds, possibly thousands of scientists. Their specialty was untraceable poisons delivered by ingenious weapons—such as a cigarette packet made in 1954 that could fire bullets filled with potassium cyanide.

In 1978, the prizewinning Bulgarian writer Georgi Markov, then working for the BBC in London, was killed by an umbrella tip that shot a pellet containing the poison ricin into his leg. After the international outcry, the Soviet Union toned down its poisoning efforts but didn’t end them. And Putin’s Russia has continued to use similar techniques. In 2006, according to an official British inquiry, Russian secret agents murdered the ex-spy Alexander Litvinenko by slipping polonium into his drink during a meeting at a London hotel. It was the beginning of a new wave of poisonings whose end is not yet in sight.