Nuisance mosquitoes are those that persistently bite humans but do not necessarily carry pathogens such as West Nile virus (WNv) or dengue. Controlling nuisance mosquitoes is important in large, populated floodplains, such as the Lower Mainland of Vancouver in the Fraser Valley, where floodwater species are known to be voracious human biters. Explosions in numbers of floodwater species, such as Aedes vexans and Aedes sticticus, during the spring freshet are also of great concern in other areas of BC, such as the Kootenays, where mosquitoes can seriously impinge upon outdoor activities in schools, homes and businesses.
The Culex team has considerable experience in monitoring nuisance species. In 2002, 2009, 2010, 2011, 2012, 2013, and 2014, Culex has been involved in a major study on behalf of BC Hydro in the Lower Duncan floodplain to investigate the effects of discharges from the Duncan Dam on mosquito production. Results showed that as in so many cases, the natural swamps and wetlands were not the problem, but rather man made areas which had been poorly drained and had been fertilized for hay production and pasture.