Iceland Has No Mosquitoes

The secret to this largely buzz-free nation lies in its erratic oceanic climate. Unlike its neighbors (Review) such as Greenland or Norway, which experience stable, cold winters, Iceland is subject to frequent and rapid temperature swings. The life cycle of a mosquito depends on predictable seasonal changes; its pupa typically hibernates under ice during a continuous winter and hatches when the ice melts in the spring. In Iceland, a sudden mid-winter thaw can trick the pupae into hatching too early. Before the mosquitoes have time to mature and reproduce, an subsequent freeze will kill them off, effectively resetting the cycle.

This climatic barrier is reinforced by the island's geology. Much of Iceland's soil is volcanic and porous, which prevents the formation of the stagnant pools of water that mosquitoes require for their larvae to develop. There is also speculation that the specific chemical makeup of Iceland's water and soil is inhospitable to these insects. It is important to note, however, that Iceland is not entirely free of biting insects; it is home to pesky midges, especially around Lake Mývatn, which translates to "midge lake". Recently, the country's long-held mosquito-free status has been challenged, as a warming climate may be creating more stable conditions for new species to survive.