SPATIAL AND CIRCADIAN OVIPOSITION PATTERNS IN AN URBAN-POPULATION OF CULEX-QUINQUEFASCIATUS

A transect of infusion-baited oviposition tubs was used at the Orange County (CA) Vector Control District facility to determine the circadia n periodicity and the influence of urban habitat factors, such as buil dings, ornamental plantings, and mercury vapor lights on Culex quinque fasciatus oviposition activity. The peak oviposition activity occurred during the first 2 h after sunset. Nearly 80% of egg rafts deposited were laid within the first 4 h after sunset and no morning oviposition al peak was detected. Urban and physical habitat factors considered ha d no effect on tub selection by ovipositing females. Linear analysis i ndicated that eggs were laid randomly among tubs. Eighty-eight percent of the rafts collected were Cx. quinquefasciatus. The remaining egg r afts were laid by Culex tarsalis, Culex stigmatosoma, and Culieseta in cidens.