Mosquito
Mosquitoes of the genus "Toxorhynchites" never drink blood. This genus includes the largest extant mosquitoes, the larvae of which prey on the larvae of other mosquitoes. These mosquito eaters have been used in the past as mosquito control agents, with varying success.
Färnebofjärden National Park
The species of insect most associated with the park and the Lower Dalälven in general are mosquitos of the genus "Aedes". Indeed, the park's wetlands are enormously productive in mosquitos, especially during the heavy spring floods. The quantity of mosquitos in the Lower Dalälven has no equivalent in Sweden besides that in the vast wetlands of Lappland. This abundance bothers not only the park's tourists during the summer but also the entire region as far as Uppsala. Between 2002 and 2008, the insecticide was used to try to regulate these populations, which needed a waiver, its use being forbidden in Sweden and contrary to the principles of the national park. However, the project was not renewed, this method not being considered a durable solution and some scientists arguing that the mosquitos make up part of the region's ecosystem.