The present distribution and predicted geographic expansion of the floodwater mosquito Aedes sticticus in Sweden
Martina Schäfer & Jan O. Lundström
Department of Ecology and Evolution / Population Biology & Conservation Biology, Uppsala University, Sweden and Swedish Biological Mosquito Control Project, Gysinge, Sweden.
Mass emergence of floodwater mosquitoes, in particular Aedes sticticus and Aedes vexans, cause substantial nuisance and reduce life quality for inhabitants of infested areas, and can have a negative
impact on the socio-economic conditions of a region. We compared the previous, present and predicted future geographic distribution of Ae. sticticus in Sweden. Previous records from the literature until 1990 list the species in three out of 21 Swedish counties. Studies from 1998 and onwards show that the present distribution of the species covers 11 counties, with highest abundances in an east-west belt in Central Sweden. Using climate data from the present and
predicted climate scenarios, the expected distribution of Ae. sticticus in 2020, 2050 and 2080 could be modelled in a GIS. As variables, mean temperatures and cumulative precipitation between May and August and degree slope were chosen. The predicted future geographic distribution of Ae.
sticticus will continue to increase and include 20 out of 21 Swedish counties. The expected temperature rise will increase the suitable area towards the northern part of Sweden by 2050. Some non-suitable areas can be found along the south-east cost due to insufficient amount of precipitation in 2050 and 2080. Modelling the expected distribution of a species using predicted climate change scenarios provides a valuable tool for risk assessments and early-warning systems that is easily applied for different species and scenarios.