As climate change expands the northern reach of many species, a new citizen science project calls on BC and Yukon residents to send blown mosquitoes so researchers can track them and the diseases they can carry.
For most hikers, camping next to a swamp can be hell.
Swarms of mosquitoes roar in a shady path around your head. They light up in the ears, neck and back. And in the space of a few seconds, their jagged jaws break into your skin, paving the way for the six-needle mouths to enter their target: your blood. Then comes the itching.
But when the evening comes for Dan Peach, he is the first to offer himself as bait.
Last summer, the mosquito researcher spent months hunting the famous insect near the province’s wetlands, lakes and rivers. On the tops of the mountains, he caught hairy mosquitoes; in coastal estuaries, it persecuted the inhabitants of tidal pools, which can survive and reproduce in the water three times the salt content of the ocean.
On a recent trip to Whistler, Peach said he got under the bridges “like a troll” in search of hidden mosquitoes.
Everything is part of an ambitious mapping project that aims to discover the reach of the 51 species of mosquitoes that are already known to exist before Christ.
From here, Peach will use the maps, combined with predicted changes in temperature and rainfall, to model how mosquitoes and the diseases they carry could spread due to a changing climate.
“We think these things have already gone further north,” Peach said. “As the weather changes and some of these conditions change, where will they be in the future?”
But first, you have to catch them.
In his lab, Dan Peach displays part of his collection of mosquitoes gathered across British Columbia. STEFAN LABBÉ / GLACIER MEDIA
In her lab at the University of British Columbia, Peach pulls out a vacuum cleaner, which looks like a large turkey, only to place the device on her lips instead of a light bulb to suck out drips of sauce. , with a sharp inhalation, vacuum. a mosquito in a filter inside.
Other mosquito repellents are even less high-tech. To catch mosquito larvae he uses “a cup on a stick.”
“If they float in the water swimming and see a shadow or something, they will dive in and hide,” he said. “So you put this cup on a stick and approach it, as if you’re approaching it.”
At other times, the researcher will deploy a trap that looks like a folding clothes basket with a lid and an opening at the top. The black and white color attracts insects, but so does the synthetic sweat of German origin.
The peach opens a cooler door to take out a half-open package full of a handful of chemicals, each a key ingredient in reproducing “the stinking person’s smell.”
“It smells like gym socks,” he says, grabbing the journalist’s nose.
In the field, German artificial sweat falls into the trap with carbon dioxide, an irresistible mixture as artificially human as Peach can get.
But there are limits to what a single scientist can do, no matter how motivated he may be. Carbon dioxide cannot be found in many small towns in BC. And no matter how much Peach travels the region, she can’t be everywhere at once.
Instead, Peach expects an army of citizen scientists to open their palms to help him measure the province’s ever-changing mosquito population, one slap at a time.
“We’re calling it ‘Ow! What just bit me? Project,'” Peach said, adding that she also accepts Yukon samples. “Basically, this summer, if you pet the mosquito, put it in an envelope and mail it to us.”
Also add the date, plus the latitude and longitude of where he was killed (you can look it up in an app like Google Maps), he says. Once the laboratory receives the sample, it will be shredded and genetically sequenced to confirm the species. In return, Peach said he would email information about what species of mosquito was slapped.
More than just a window biting you, a slap in the face and a trip to the post office offer BC and Yukon residents a helping hand to prevent future crises.
An unfathomable trail of bodies
It is difficult to underestimate the risk that mosquitoes pose to human health. By acting as a vector for everything from yellow fever and dengue to malaria and Japanese encephalitis, the mosquito has killed humans on an almost unfathomable scale.
“Mosquitoes are the deadliest animal in the world,” Peach said.
Several researchers, including Peach, suspect that malaria alone has killed half of the people who have ever existed. Or as Bill Gates said in 2014, mosquitoes kill more people than people.
(At the time, mosquito-borne diseases killed about 725,000 people a year, compared to 425,000 people who died at the hands of other humans.)
Since then, Gates and others have invested large sums of money in malaria control programs, reducing mortality from the virus by 36 percent between 2010 and 2020. But by the end of the decade, an estimated 627,000 people still died from the disease. And it is known that at least 240 million more people suffered from the disease that year.
As one influential book on the deadly trail left by insects put it, “The mosquito remains the world’s foremost destroyer and killer and the world’s most distinguished killer.”
“Mosquitoes had this very profound influence on humans,” Peach said. “And because humanity has been one thing, basically, and they continue to do so today.”
“So there’s a very real risk here. And more or less because of that, we focus on that area, and we don’t really pay as much attention to the other things that mosquitoes do in an ecosystem.”
A dangerous vector is heading north
Today, someone in Eastern Canada might be forgiven for thinking that BC’s Lower Mainland has always been a mosquito-free refuge.
“Sixty years ago, before they spoke along the Fraser [River] and drained Sumas Lake, the Lower Mainland was considered worse than the prairies by the settlers who had passed through, ”Peach said.
As recently as the 1960s, the province suffered outbreaks of mosquito-borne western equine encephalitis, and a century ago, the Interior had cases of malaria.
“It simply came to our notice then. We have to keep an eye on it, “Peach said.
A recent study, for example, found that the Aedes aegypti mosquito could spread to parts of British Columbia under various scenarios of global warming emissions. The mosquito species is a vector of a number of pathogens that are dangerous to humans, such as chikungunya, dengue, Japanese encephalitis, zika, West Nile, and yellow fever viruses.
Aedes aegypti, a species known to spread a number of diseases dangerous to humans, is expected to spread to parts of British Columbia due to climate change. – Dan Peach
There are more than 3,500 species of mosquitoes on the planet. About 80 of them are in Canada. But it’s not clear how tiny creatures move.
Of the more than 50 species of mosquitoes in BC, a handful are known to be invasive, including the northern house mosquito (Culex pipiens), which carries the West Nile virus, and the Japanese rock pool mosquito. (Aedes japonicus), a species that has been in the province for a decade.
A mosquito that bites during the day in the woods is known to be a mosquito in the rock pool that carries a variety of diseases, such as West Nile virus and two forms of encephalitis: swollen brain infections and headaches. and that can cause vomiting, seizures. , and in some cases, death.
But while BC is home to a number of mosquitoes known to spread disease, its climate is not yet ideal for tracking some of the mosquito-borne vectors.
This could change in the coming years, as warmer summers and wetter winters extend the reach of many species northward, even across the oceans.
“In recent years, we’ve been seeing some of the West Nile vectors in places further north than before,” Peach said.
He points to Culex pipiens, which has recently appeared in Prince George.
“It was never thought to go so far north,” he said, pointing to the strange case south of the Interior or Lower Mainland.
And while it’s likely to be too cold up there for the West Nile to spread in the wild, there’s a risk that an infected person could carry the virus with them in a bird, human, and bird spread event transmitted to through the bites of the invasive Culex pipiens.
Mosquitoes are only half the image.
“The weather is definitely limiting the spread of these pathogens,” Peach said. “You need it hot enough long enough to spread.”
“There may be areas where there is nothing to worry about now, but maybe, you know, between 40 and 50 years in the future, we need to worry about pathogens like the West Nile.”
The unrecognized role of a killer in sustaining life
Not all mosquitoes are pathogens loaded with pathogens.
In fact, only female mosquito species take blood, and then only to develop their eggs. Many species do not even target humans and only a few carry pathogens that are dangerous to our health.
Mosquitoes are attracted to flowers as much as people. Adult mosquitoes feed on vegetable sugar, bouncing from flower to flower like a bee, in a process that seems to have developed at least since the Middle Cretaceous period, more than 100 million years ago.
In a strange adaptation, mosquitoes take advantage of ants and their habit of cultivating aphids to collect honeydew.
As Peach said in a recent article, “When a mosquito puts its mouthparts into an ant’s mouth and caresses the ant’s head with its antennae, it tricks the ant into regurgitating and sharing its honeydew.”
They also act as a massive food source, a link that promotes the transfer of energy from aquatic environments, where their larvae filter microbes, algae and dead …