Three types of experiments were conducted to compare mean dipper counts of Culex tarsalis with estimates of absolute density in rice fields. Data from stocked enclosures in rice fields, field population surveys and field populations sampled from enclosures were used to develop linear regression equations describing the relation between counts and population density. There were good correlations (r2 > 0.93) for the regressions and the regression lines were similar for third and fourth stage larvae and pupae. Combined with a standardized dipping procedure these data can be used to estimate the absolute population from the mean dipper count.