Mosquitoes in Iceland confirmed for first time, monitoring needed to determine establishment: Entomologis

 Discovery Ends Iceland’s Mosquito-Free Status, Scientists Cite Global Warming as a Likely Factor

PTI, New Delhi, Oct 23, 2025 :  A citizen of Iceland sighted mosquitoes at his home last week and sent photographs for confirmation — a scientist has confirmed this as the country's first instance of the insects, though further monitoring is needed to determine if the species has established itself.

The presence of the mosquitoes could suggest a recent introduction, possibly transported via ships or shipping containers, said Matthias Alfredsson, an entomologist at the National Science Institute of Iceland, in an email to PTI.

While the species, identified to be a Culiseta annulata, may be habituated to cold climates, warmer conditions driven by global warming could make it easier for the mosquitoes to survive and establish themselves here, Alfredsson said.

Iceland, long celebrated as one of the few mosquito-free places on Earth, has lost that distinction. Scientists have confirmed the presence of mosquitoes in the island nation for the first time, marking yet another visible consequence of a rapidly warming planet.

"I could tell right away that this was something I had never seen before," Hjaltason told an Icelandic daily, Morgunbladid, adding with a touch of humour, “the last fortress seems to have fallen.”

Hjaltason collected three specimens — two females and one male — and sent them to the Icelandic Institute of Natural History for verification.

Entomologist Matthias Alfredsson confirmed the insects as Culiseta annulata, a cold-resistant mosquito species found across parts of Europe and North Africa.

“These specimens were collected from wine ropes meant for attracting moths,” Alfredsson was quoted as saying by The Guardian. “Culiseta annulata can survive Icelandic conditions by sheltering indoors during winter — in basements, barns or other warm spaces.”

Researchers attributed Iceland’s mosquito-free status to its unique freeze-thaw cycle. The country experiences three major freezes each year that thaw only once annually — an inhospitable rhythm that disrupts mosquito breeding. Some also pointed to the chemical composition of Iceland’s water and soil, suggesting the insects struggled to adapt to the environment. But as the nation’s climate warms, those long-standing barriers are breaking down.

Until this month, Iceland and Antarctica were the only two places on Earth considered completely free of mosquitoes. Scientists had long wondered why the insects, which thrive even in some of the planet’s coldest regions, never managed to establish themselves there.

According to a recently published report, Iceland’s temperatures are rising four times faster than the northern hemisphere average. The country experienced a record-breaking heat spell this spring, with temperatures hitting 26.6°C at Egilsstadir Airport — the highest ever recorded in May.