Dispersal, survivorship, and host selection of Culex erythrothorax (Diptera : Culicidae) associated with a constructed wetland in southern California

Three mark-recapture studies were carried out at a constructed wetlands fac ility in San Jacinto, CA, to examine the dispersal and population ecology o f the most abundant host-seeking mosquito, Cubr erythrothorax Dyar, collect ed in carbon dioxide-baited traps. Recapture rates were 0.3, 7.4, and 13.9% for August, September, and October, respectively. The mean distance travel ed per night was approximate to 0.5 km, and females were not recaptured far ther than 2 km from the release site. Most marked individuals (greater than or equal to 99.5%) were recaptured within 0.5 km of the release point. Mar ked individuals were recaptured for 33 d after release. Horizontal estimate s of survival calculated using recapture data were 0.89, 0.87, and 0.84/d f or August, September, and October, respectively. Temporal differences in th e recapture rate were attributed to the effects of blood meal acquisition o n host-seeking activity versus effects of mortality and strong developmenta l site fidelity on weekly recapture rates. Partially engorged females colle cted by CO2-baited traps at the wetland fed predominantly on cattle indicat ing that host-seeking females were using hosts at dairies surrounding the w etland and were returning to the wetland for resting before seeking an addi tional blood meal. Estimates of the gonotrophic cycle length and survivorsh ip (vertical estimates) were problematical because of the low parity rates for females collected by CO2-baited traps. Limited dispersal and long survi val of Cx. erythrothorax are important factors in the development of large populations at constructed wetlands.