For centuries, Iceland’s icy winters and isolated landscape have kept one of the world’s most persistent pests at bay. But this October, that streak ended. Scientists confirmed the first-ever discovery of mosquitoes in the wild in Iceland, a nation long considered – alongside Antarctica – one of the planet’s last mosquito-free zones. The find has sparked scientific excitement, environmental concern, and no small amount of local curiosity about what it means for the country’s fragile ecosystem in a rapidly warming world.
The story began at dusk on October 16, 2025, in Kiðafell, Kjós, a glacial valley about 20 miles north of Reykjavik. Björn Hjaltason, a local insect enthusiast, was out observing moths using wine-soaked ropes – a technique that lures insects with the scent of fermenting fruit. But what landed on his wine ribbon that evening was no moth. “I could tell right away that this was something I had never seen before,” Hjaltason later posted in a Facebook group dedicated to Icelandic wildlife, as reported by local media. “The last fortress seems to have fallen.”
Recognizing the potential significance of his find, Hjaltason quickly collected the insect and reached out to Matthías Alfreðsson, an entomologist at the Natural Science Institute of Iceland. Alfreðsson drove out the next day to Hjaltason’s home, and together they captured two more specimens. In total, they secured three mosquitoes: two females and one male. The insects were sent to the Icelandic Institute of Natural History for confirmation.
Alfreðsson identified the newcomers as members of the Culiseta annulata species – a type of mosquito native to a vast stretch of the Eastern Hemisphere, from North Africa all the way to northern Siberia. What sets Culiseta annulata apart from many of its relatives is its remarkable ability to survive cold winters. According to Alfreðsson, “This allows them to withstand long, harsh winters when temperatures drop below freezing.” The species achieves this by seeking out sheltered places to overwinter as adults, a trait that might just give it a fighting chance in Iceland’s notoriously frigid climate.
Before this, the only other mosquito ever found in Iceland was a lone specimen of a different species, discovered years ago on an airplane at Keflavík International Airport. But as Alfreðsson told CNN, this new discovery is the “first record of mosquitoes occurring in the natural environment in Iceland.”
While the appearance of mosquitoes in Iceland is a biological milestone, it’s also raising pressing questions about how and why these insects have arrived now. One theory points to the nearby port of Grundartangi, just six kilometers from Hjaltason’s home. “One always suspects Grundartangi – it’s only about six kilometres from me, and things often arrive with ships and containers, so it’s possible something came in that way,” Hjaltason speculated. He added, “But if three of them came straight into my garden, there were probably more.”
The timing of the discovery has not gone unnoticed. Iceland has been experiencing a series of record-breaking heatwaves. In May 2025, temperatures in parts of the country soared more than 18 degrees Fahrenheit above normal. The heatwave lasted ten consecutive days, with the mercury peaking at 26.6°C (almost 80°F) at Egilsstaðir Airport – the hottest May day ever recorded in Iceland. According to an analysis by the World Weather Attribution network, this extreme heat was made 40 times more likely by climate change.
Such temperature spikes are highly unusual for Iceland, where May temperatures rarely exceed 20°C and heatwaves typically last only a couple of days. As reported by the Global Heat Health Information Network, these shifts could have “significant” impacts on cold-adapted ecosystems like Iceland’s. The United Nations climate body has stated unequivocally that human activity has warmed the atmosphere, oceans, and land, making events like Iceland’s record heat increasingly common.
Mosquitoes, notorious for thriving in warm and humid environments, are expected to be among the few real winners as the planet heats up. Research cited by CNN notes that rising temperatures allow mosquitoes to grow faster, live longer, and expand their range into previously inhospitable regions. Indeed, Culiseta annulata is already common in parts of Europe and North Africa, and has been found in places as far north as Scandinavia.
Still, experts urge caution in drawing a direct line from climate change to this particular mosquito incursion. “Climate change may have made this more likely, but I’m not convinced it’s a clear, direct impact,” said Colin J. Carlson, an assistant professor of epidemiology at Yale University School of Public Health, in an interview with CNN. “The truth is, we just don’t know a lot about endemic mosquito range shifts that are already happening.” Alfreðsson echoed this uncertainty, stating he’s not sure climate change played a role in the discovery, but “warming temperatures are likely to enhance the potential for other mosquito species to establish in Iceland, if they arrive.”
The implications of mosquitoes taking up residence in Iceland go beyond mere scientific curiosity. Mosquitoes are infamous vectors for diseases such as West Nile virus, malaria, and dengue fever. While Culiseta annulata is not a major carrier of these illnesses, its presence is a reminder that changing climates can bring unforeseen challenges to public health and biodiversity. Iceland’s cold climate and limited stagnant water have historically prevented mosquitoes from breeding, according to the World Population Review. But as the climate shifts, those barriers may be weakening.
For now, the future of mosquitoes in Iceland remains uncertain. Alfreðsson and his colleagues plan to monitor the area in spring 2026 to see if the species can survive the winter and “truly become established in Iceland.” If they do, the country’s status as one of the world’s last mosquito-free refuges will be a thing of the past.
In the meantime, Hjaltason’s discovery has captured the imagination of a nation long accustomed to being spared the buzzing nuisance. Whether this is the first sign of a new normal or just a fleeting anomaly, Icelanders – and scientists worldwide – will be watching closely as the story unfolds.
