Warming Arctic could bring more mosquito swarms

Kevin G. Smith/Design Pics Inc./Alamy

Warming Arctic could bring more mosquito swarms

There’s an arms race going on among insects in the Arctic, where temperatures are increasing faster than anywhere else on the planet—and mosquitoes are winning, according to a new study. Warming temperatures may both speed up the development of the insects and increase the rate at which other predators—such as the larval beetle—eat them. To find out how climate change will affect the overall survival of Arctic mosquitoes (Aedes nigripes), a team of researchers placed mosquito larvae taken from ponds in western Greenland into chambers with temperatures ranging from 4°C to 19°C, simulating temperatures measured in the ponds during mosquito development, and then timed how long it took for the adults to emerge. In separate chambers, they also assessed how many mosquitoes the larval beetles would eat at various temperatures. Both the mosquitoes’ development rates and mortality rates increased as the temperatures increased, the researchers report online today in the Proceedings of the Royal Society B. But a model that incorporated both rates showed that the mosquitoes’ overall probability of survival is higher at higher temperatures. That’s because faster development meant less time exposed to predators—and also brought the mosquitoes’ life cycle more into sync with that of the caribou they feed on, which are less mobile as they calve in early spring. Even with more beetles munching on them, an increase of 2°C—the current target cap for global warming—bumps the average mosquito’s probability of survival into adulthood by 53%.