Mosquitoes in Iceland appear to be losing ground this summer. According to emeritus biology professor Gísli Már Gíslason, virtually no mosquitoes have been spotted across the country so far in 2026 — welcome news following last year’s first-ever confirmed sightings of two separate species on the island.
Key takeaways
- Almost no mosquitoes have been seen in Iceland during the summer of 2026, according to a leading biologist.
- Two species were detected in Iceland for the first time in 2025 — Culiseta annulata in Kjós and an unidentified species in a horse stable in South Iceland.
- A specialist is actively working to eradicate remaining larvae at the South Iceland stable using a non-toxic silica-based substance.
- If no adults appear this summer, experts believe Culiseta annulata likely did not survive the winter.
What happened when mosquitoes were first found in Iceland?
Last year, 2025, marked a notable first in Icelandic natural history: two mosquito species turned up on the island for the first time on record. One was Culiseta annulata, discovered in Kjós — a valley roughly 40 kilometres northeast of Reykjavík — and the other was an unidentified species found in a horse stable somewhere in South Iceland (Suðurland). Both findings caused genuine concern among biologists, given that Iceland has long been one of the very few countries in Europe with no native mosquito population.
So far this summer, however, neither species has shown up again. Gísli Már Gíslason told Morgunblaðið that he had expected to see Culiseta annulata reappear around the turn of the month, but it has not materialised. He notes that the species has a wide range — from northern Norway all the way down to the Mediterranean — and typically lives three to four weeks when summer temperatures hover around 20°C. Because Iceland’s summers run cooler than that, its lifecycle here remains poorly understood.
The practical implication is straightforward: if the mosquito fails to appear at all this season, it almost certainly did not survive an Icelandic winter. That would be a relief, because establishment — breeding successfully through cold months — is what would make any invasive insect species a lasting problem rather than a one-off curiosity.
How are authorities dealing with mosquito larvae in Iceland?
The situation at the South Iceland horse stable is slightly more active. A small number of mosquito larvae have been detected there, and entomologist Matthías Alfreðsson is leading an eradication effort. He has sourced a specialist substance from England — not a conventional pesticide, but a silica-based material that physically blocks the breathing of larvae and pupae, preventing them from reaching adulthood. Gísli describes the approach as non-toxic, which matters in an agricultural setting around horses.
The larvae are thought to have survived the winter in the stable’s manure environment — a common overwintering strategy for mosquito larvae in cold climates. But with targeted treatment underway, the expectation is that this pocket population can be eliminated before any adults emerge and potentially breed further.
Gísli still urges a degree of caution. He has not ruled out the possibility that adult mosquitoes could yet appear later in the summer. Iceland’s weather in late July and August can, in certain years, push into the kind of warmth that would accelerate insect development. So while the news right now is encouraging, the story is not quite finished.
For anyone curious about how invasive insects are tracked across Europe, the European Centre for Disease Prevention and Control’s mosquito surveillance map gives useful context on how rapidly species like Culiseta annulata have spread across the continent in recent decades.
Frequently asked questions
Are there mosquitoes in Iceland in 2026?
As of late July 2026, almost no mosquitoes have been observed anywhere in Iceland. Experts say this is a positive sign, but they are not yet ready to declare the country completely free of the two species first detected in 2025.
What mosquito species were found in Iceland for the first time?
Culiseta annulata was found in Kjós in 2025, and a second, unidentified species was discovered in a horse stable in South Iceland. Both were the first confirmed mosquito finds in Icelandic history.
How is Iceland trying to get rid of mosquitoes?
Entomologist Matthías Alfreðsson is treating the affected stable in South Iceland with a silica-based substance imported from England. The material prevents larvae and pupae from breathing without the use of conventional pesticides, making it safe for use around livestock.
