While we bemoan the negative effects of climate change -- melting ice, voracious polar bears and the like -- one critter is loving life. It's the mosquito! The Arctic mosquito, to be precise. And everybody loves mosquitoes, right? What awesome, great, wonderful news.
According to a study published Tuesday in Proceedings of the National Academy of Sciences B, warmer weather in the Arctic is leading to bigger mosquitoes -- and greater numbers of them. According to the researchers' predictive models, the problem could get much worse as temperatures increase -- and caribou populations could suffer as a result.
The Dartmouth College researchers focused on Western Greenland, where they collected field observations of the millions of local mosquitoes in 2011 and 2012.
"There are just so many mosquitoes in that part of the Arctic, more than you could possibly imagine without visiting," lead author Lauren Culler, a postdoctoral researcher at Dartmouth's Dickey Center's Institute of Arctic Studies, told The Post.
Culler, who's less of a mosquito hater than I am, was rightfully worried that mosquito populations might drop.
"We thought in a warming Arctic the predators might more eat mosquitoes on any given day, and that the mosquito population might actually go down," Culler said.
For most of us, it's difficult to imagine wanting to save the mosquito. "I think we have yet to fully appreciate the role of mosquitoes, in the Arctic in particular," Culler said. But the swarms of bugs pollinate many of the local plants, and they're also an important source of food for birds. "We definitely don’t want them to disappear completely," she said.
But it turns out that the Arctic mosquito population is doing just fine. While other bugs did eat more mosquitoes as the weather warmed, the hungry predators couldn't enjoy the buffet for long.
If a mosquito is going to get eaten, it's likely to happen during its larval or pupal stage, when it's living in the water and largely helpless. But Culler and her team found that every 1 degree Celsius increase in temperature shortened the average time spent in larval and pupal stages by about 10 percent. In other words, warm weather makes mosquitoes grow up faster.
Overall, the study predicts, mosquitoes would have a 50 percent greater likelihood of surviving to adulthood if temperatures raised by just 2 degrees Celsius. Studies have shown that the Arctic is warming twice as fast as anywhere else on the planet.
Already, more mosquitoes are surviving into adulthood than before, entering the stage of life where they become a nuisance to humans -- and more importantly, to caribou.
"Mosquitoes can actually drive caribou movement," Culler explained. "Caribou are known to run to the top of windy ridges or flee to a snow patch in response to nuisance from mosquitoes."
Any time and energy they spend fleeing to remote areas is detrimental: It takes away from the time and energy they could have spent finding food. Previous research suggests that a lack of high-quality food makes caribous less likely to reproduce successfully.
Culler was even more disturbed by the way the warm weather changed the time at which the mosquitoes emerged. There was a full two-week difference between the peak mosquito season from 2011 to 2012, Culler said, caused by warm weather. When the mosquito peak shifted, it happened to fall just as the new caribou calves were being born -- making the insects' pesky influence that much harder to bear.
And those helpless, largely immobile calves give female mosquitoes the perfect source for the blood meal they need in order to reproduce, which could increase the population even further.
"We're working to understand what happens to these adults as the climate warm," Culler said. "We know that more of them are making it to that life stage, but knowing how they fare reproductively will give us some long-term sense of how the population might change."