Too Cold for Comfort?

For many years, Iceland has enjoyed the luxury that no other country has experienced: a mosquito-free environment. Despite having a very similar climate to its neighbors, including Norway and Greenland, Iceland remained an anomaly as the only habitable place on Earth without these annoying pests. However, several sightings from Western Iceland in October 2025 have reported the country's first mosquitos. Scientists have since confirmed the presence of a small mosquito population living in Iceland, which is a significant ecological shift.

Many scientists believe that climate change as the most likely explanation for this change. Iceland is known for its quickly changing weather and temperatures, making it very difficult for young mosquitos to live. When they are young, they require still water sources in order to complete the first stages of their life cycles. However, Iceland's ponds tend to freeze, thaw, and freeze again in the variable climate, which makes it nearly impossible for the mosquitos to thrive. The species found (Culiseta annulata) is known to be capable of living in colder temperatures, so with the warmer climate, this species has the potential to be permanent residents.

Though in recent years, Iceland has been warming much faster than the global average, causing fluctuations in its seasonal patterns. Spring has gotten much warmer and arrived a lot earlier, so lakes and ponds remain liquid water for longer spans of time. This change in conditions is something that mosquitos can take advantage of. Researchers claim that this change may finally allow the species to thrive in this area.

However, not everyone in the scientific community is convinced that climate change is the entire or even primary factor. Skeptical researchers suggest that the introduction of mosquitos is something that we have seen before. A few years ago, a mosquito was spotted in Iceland and was brought there by a container ship, indicating that the mosquitos may have arrived from other imported goods, planes, or ships. They also state that a few insects qualify as a stable population. In their eyes, Iceland's environment may still be too unstable for mosquitos to establish long-term populations, even if the area is warming.

The confirmed captures of the mosquitos remain limited, leaving this debate unresolved for now. Still, the arrival of these mosquitos demonstrates how much we still have to learn about Earth's unique ecosystems and what shapes them.