Mosquito numbers unusually low in southern Finland

Southern Finland has seen an unusually low number of mosquitoes this spring, according to a report by Finnish public broadcaster Yle.

The dry spring has slowed mosquito development, particularly in the region. A low-snow winter, prolonged cold nights, and a dry April prevented mosquito eggs from hatching into larvae, said Jaakko Kullberg, a senior nature expert at Sitowise.

Rainfall expected this week is likely to change the situation, Kullberg said. Mosquitoes will gradually increase in number, though their development from egg to flying insect takes several weeks. He estimates they will be widespread in southern Finland within 3–4 weeks.

Despite climate change altering habitats, Finland’s thousands of lakes and waterways ensure mosquitoes will remain abundant, Kullberg noted. While species may shift northward as temperatures rise, the insects will persist.

Human activity, such as the drainage of millions of kilometers of forestland, has also influenced mosquito populations, he added. In urban areas, the Culex pipiens molestus—or “city mosquito”—thrives, often breeding in drains, damp tunnels, and other water-collecting spots. This species, which feeds on mammals and humans, is known to cause stronger allergic reactions and itching.