Dispersal Experiment of Culex tritaeniorhynchus in Nagasaki Area (Preliminary Report)

Abstract

To make clear the dispersal of Culex tntaeniorhynchus females in rather hilly Nagasaki area, a mark-and-recapture method was applied in summer, 1967. From 3 points, differently marked 156,500 females in total were released at 4 AM, July 29, and recapture catches were made by light traps at 19 points in the area of 8km×10km on 7 succeeding nights from the release. From the results obtained, it is seen that (1) the females disperse generally along valleys and seacoast; (2) usual flight range seems to be at least 1.0km; (3) some of the females have an ability to fly at least 2.0km without landing, and to disperse at least 8.4km. Also a method of estimating daily loss rate of the released females by the daily recapture data was described.