Abundance and Seasonal Occurrence of Psorophora columbiae in a Northeast Arkansas Ricefield Community

Increased population levels of the dark ricefield mosquito, Psorophora columbiae (Dyar and Knab), have been shown to be associated with rice cultivation in Arkansas and several other states. Four standard New Jersey light traps were operated daily between May 30 and October 2 of 1981 and 1982 to determine the relative abundance and seasonal occurrence of this species in NE Arkansas. The effect of trap distance from nearby rice on the number of adult P. columbiae collected was assessed by comparing weekly totals from 2 traps located within 0.9 km of rice fields with totals from 2 traps situated beyond 1.2 km. A total of 68,155 mosquitoes representing five genera was trapped during this study. Of this number, 45,760 (67.1% of all mosquitos captured) were P. columbiae. Female adults comprised 98.8% of the trapped ricefield mosquitoes. The peak period of abundance for this species was found to occur between mid-July and late August and was closely associated with area rice-culture practices. The capture of more than 95.0% of all P. columbiae adults within 0.9 km of rice fields confirmed the reported short flight range of this species