Tiger mosquitoes, Asian hornets and bed bugs: what climate change means for Europe’s ‘demographic pests’ lurking at the Paris Olympics

About an hour from Vienna, the Penny Markt in Krems an der Donau prides itself on two things: low, low prices and the provenance of its fresh meat and produce. But on a balmy August day last year, shoppers looking for a locally sourced bargain found a rather more exotic, if less welcome, surprise lurking among the boxes of bananas.

The culprit was a stowaway Brazilian wandering spider, an 11cm black and red arachnid with a bite that causes seizures, hypothermia, death and, if you’re the male type, a particularly painful case of uncontrolled erections. You can imagine the shock.

The store closed for preventive disinfection and the spider escaped and was never heard from again. But it is not the only invasive bug that has appeared in European tabloids lately.

France has acquired an unfortunate pre-Olympic reputation for rampant bed bug infestations, and Paris deputy mayor Emmanuel Grégoire warned people that “no one is safe.” You can catch them anywhere,” and reports of Eurostar bloodsuckers causing panic in London.

Tiger mosquitoes, which can transmit dengue and Zika, have also been seen across the country, prompting authorities in Paris to hire entomological “detectives” to track their breeding sites.

Meanwhile, the Turkish pharmaceutical industry is eyeing Europe as an interesting new export market for scorpion antivenin.

Medical laboratory staff hold a scorpion at a vaccine company in Türkiye.

Kemal Karagoz/Anadolu Agency/Getty Images

Is climate change to blame for this apparent arthropod invasion?

The reality is rather less apocalyptic than the headlines suggest, says Dr Matt Green, principal entomologist at UK-based global pest control company Rentokil Initial, which has operations across the continent.

We are not even close to dengue becoming endemic. Reports of bed bugs in French beds increased largely because people saw horror headlines and started looking under their mattresses. And if we’re seeing more invasive species overall, it’s not largely due to rising temperatures.

“I am often asked how climate change is affecting our business. Well, given that humans have already transported all major pests to virtually every country and certainly to all major centers of human activity, not as much as you might think,” says Green. Fortune.

Is climate change to blame for this apparent arthropod invasion?

The good news is that those who are worried about encountering Brazilian wandering spiders can relax.

Most species need more than just a rise in temperatures to establish themselves in new and very different ecosystems. For example, the docks at Sheerness, near London, have had a population of 10,000 yellow scorpions for centuries, ever since merchant ships brought them from mainland Europe, but these harmless creatures have not spread because conditions are not suitable.

What is climate change doing to Europe’s pest population?

This is not to say that climate change is not affecting Europe’s pest profile.

Termites, long a problem in Mediterranean countries, are making their way into northern Europe with rising temperatures, although the relative lack of wooden buildings means they are unlikely to cause widespread economic damage there.

Aedes Mosquitoes (the genus that includes the tiger mosquito) are well established in Italy and reach France, meaning countries like Switzerland are unlikely to be spared.

“Europe is already seeing how climate change is creating more favorable conditions for invasive mosquitoes to spread to previously unaffected areas,” Andrea Ammon, director of the European Center for Disease Prevention and Control, told the BBC. .

Fortunately, these are not the type that transmit malaria; that is the Anopheleswhich is unlikely to spread to Europe due to the absence of large bodies of stagnant water which, unlike Aedes—It needs to reproduce.

Asian hornets in Europe are important predators of bees.
Asian hornets in Europe are important predators of bees.

Jonathan Raa/NurPhoto via Getty Images

The same can’t be said for Asian hornets which, depending on where you live, could soon come to picnic near you. “They are moving through France quite easily, and there have been cases where they have overwintered in the UK, which means we probably already have them, so make peace with that,” says Green.

Then there are bed bugs. Even before the recent surge, infestations were costing the French economy 230 million euros ($246 million) a year, according to the Anses health agency. The calls can cost hotels thousands of dollars in treatments and lost revenue, and could create hysteria and panic during the Paris Olympics.

A pest control worker shows a photograph of a bed bug infestation in Paris, France.
A pest control worker shows a photograph of a bed bug infestation in Paris, France.

Nathan Laine/Bloomberg via Getty Images

These six-legged vampires may have been there all along, but they prefer a warmer climate.

“When the temperature inside your home is 25 to 26 degrees Celsius (77 to 78.8 Fahrenheit), bed bug eggs take only five days to hatch. Under normal conditions, when the temperature is around 20 degrees Celsius, it takes 10 days,” explains entomologist and co-founder of the National Institute for the study and fight against bedbugs, Jean-Michel Bérenger. cabling during the height of the panic last year

How Europe’s pests are changing beyond climate change

Whether helped by rising temperatures or not, the pests we are likely to see the most are the ones that are best suited to humans and our behavior, and it is our behavior that helps them spread.

In rural settings, this usually occurs through monocultural agriculture, although sometimes all it takes is a tendency to import non-native plants.

The oak processionary, a species endemic to southern Europe, which damages forests and releases hairs that can irritate the skin, eyes and respiratory tract, gained a foothold in the UK in the 2000s, when an oak was sent from Europe. Ironically, it happened very close to the Royal Botanic Gardens, Kew, where authorities monitor this sort of thing.

The web of the oak processionary on the bark of an oak.
The web of the oak processionary on the bark of an oak.

Stefan Puchner/Picture Alliance via Getty Images

However, it is the urban pests that you are most likely to notice.

Rats, mice, cockroaches, and the like share characteristics that make them ideal for living intimately with humans, whether we want it or not. They are small, capable of crawling through tight spaces, generally dark and nocturnal, which makes them difficult to detect. Crucially, they are also omnivores.

“They are enormously flexible, so they won’t mind a degree or two (temperature change). They already live in air-conditioned buildings,” says Rentokil’s Green. “Some moths in warehouses barely fly these days. There’s no need. They have simply been living in a world full of food, being transported by humans. “It’s an incredible life.”

Sometimes it is a well-intentioned or necessary change in human behavior that helps urban pests proliferate.

Media frenzy aside, bed bug populations did will increase rapidly throughout the world at the beginning of the 21st century. In Australia, the increase was between 500% and 4,500%; In New York City, bed bug complaints to the council increased from 537 in 2004 to 10,985 in 2009, although they have since decreased.

Entomologists attribute the resurgence to the end of the DDT era: the infamous insecticide dramatically reduced the number of insect pests globally in the mid- to late 20th century, before serious environmental and health concerns ended its use and species will begin to develop resistance. In essence, we are returning to historical norms of a period of unusually low insect activity.

Don’t expect this to change. Although the pest control industry is implementing increasingly sophisticated monitoring strategies and “physical” interventions, such as bed bug steam room cleaning, moving away from chemical controls means we lose what had been a powerful weapon against infestation. .

Something similar could be about to happen with rats, at least in Europe, where regulators have an increasingly negative view on the use of anticoagulant rodenticides.

This may be for good reasons, but it has pest controllers nervous. As someone said off the record, “There is a whole generation of pest controllers who have been trained to put rat poison in bait boxes. If you take that away from the market, what do you have left? Quote aliensWhat are we supposed to use, harsh language?

The future

Humanity has driven many species to extinction, mostly unintentionally, and continues to do so. However, the species that at least some of us would like the least have proven to be stubbornly resilient. Almost by definition, pests thrive when we do.

So what can we expect? In Europe, climate change and human activity are unlikely to make deadly spiders a regular part of grocery shopping or cause tropical levels of mosquito-borne diseases.

But they will alter the fauna populations with which we share our environment. Get used to Aedes and Asian hornets; Be on the lookout for rats and bed bugs.

However, what may change the most is our expectation of what pest control means. With the spray first, ask questions later approach firmly consigned to the history books, eliminating pests at their first appearance may end up being remembered as a very 20th century idea.

Leave a Comment