Factors influencing the outcome of mark-release-recapture studies with Culex tarsalis (Diptera: Culicidae)

Three potentially important aspects of mark-release-recapture experimentation were addressed: 1) source of mosquitoes for release, 2) time of release, and 3) weather during recapture. Culex tarsalis Coquillett mosquitoes collected as adult host-seeking females from dry ice-baited traps (CO2 traps) operated within the study area (local) were recaptured more frequently than females collected from traps operated outside the study area (foreign) or reared from field-collected immatures (reared). These results supported published studies on Anopheles and Ochlerotatus that indicated mosquitoes may "memorize" flight paths within their environment. Releasing gravid females provided a potentially useful replacement for reared females, because these gravids oviposited at wetlands and then dispersed to upland traps. Releasing local, foreign, or reared mosquitoes just after sunrise or just before sunset did not alter recapture success or the distance dispersed. Elevated wind speeds inhibited dispersal from protected microhabitats with citrus orchards and resulted in most recaptures being found at the leeward portion of the orchard.