Surveillance is an important step in controlling the spread of arboviruses and mosquito-borne pathogens. Reliable data is needed to show how surveillance programs can be streamlined, and to increase the efficiency of larviciding operations. Knowing where mosquitoes prefer to oviposit will decrease the time spent looking for breeding sites in surveillance operations and will also help target larviciding activity. Oviposition attractants, such as hay infusions, are often used in surveillance operations to entice females to lay eggs in artificial pools. In the literature, there are conflicting reports as to the actual attractancy of these infusions. In this study, blood-fed females given a choice of oviposition sites in the lab are appearing to show a preference for tap water over strained and unstrained hay infusion. This may indicate that tap water could be used in surveillance activities in place of comparatively labour-intensive hay infusion or sod preparations. Further trials are currently being conducted to confirm this hypothesis. Field trials looked at the minimum size of ovipool that could be used for surveillance. Wooden ovipools of three different sizes (40 X 30 X 15cm, 30 X 15 X 15cm, and 10 X 10 X 15cm) were set up at the Glenlea Research Station, located 20 km south of Winnipeg, from May 15th to August 31st 2001. No oviposition in the smallest pools but there was substantial oviposition in the two larger sized pools. Traditional surveillance programs conducted in Manitoba use 1m by 1m by 10cm pools, which can be cumbersome to set up and time-consuming to maintain. The data collected appear to indicate that either the 40 X 30 X 15cm or the 30 X 15 X 15 cm pool could be used in place of the larger pools.
Species 1: Diptera Culicidae Culex tarsalis
Species 2: Diptera Culicidae Culex restuans
Species 3: Diptera Culicidae Culiseta inornata
Keywords: oviposition
The ESA 2001 Annual Meeting - 2001: An Entomological Odyssey of ESA