Survey of 13 Polk County, Florida Lakes for Mosquito (Diptera: Culicidae) and Midge (Diptera: Chironomidae) Production

Abstract

A survey was conducted at 30 sites in 13 lakes in Polk County, Florida to: (1) determine the extent of mosquito and midge production in the lake sites, (2) define more precisely some of the environmental factors that influence mosquito and midge densities, and (3) determine if the physical appearance of a site would enable accurate estimates of the mosquito and midge production potential. Although the emphasis of this survey was on Coquillettidia perturbans (Walker), data were collected on the mosquitoes Anopheles, Culex, Mansonia, and Uranotaenia and the chironomid midge Glyptotendipes paripes Edwards. Results of previous studies in marshes indicate that higher numbers of Coquillettidia larvae are found in sites with (1) dense stands of emergent vegetation, (2) substrates characterized by a thick layer of detritus, (3) water depths less than 1 m, and (4) dense stands of shoreline vegetation. Production in sites with these characteristics was found to be greater than previously realized. Estimates of Coquillettidia production made at the beginning of the study were found to be correct in 20 of the 30 instances. Production potentials that were over- or under-estimated were due primarily to changes in trap locations (due to fluctuating water levels) in which dramatic changes in habitat conditions occurred. It appears that, with only cursory observation, an accurate estimate of a site's potential for mosquito and midge production can be made.