Data from a 5 year collection of Culiseta incidens (Thomas) in the foothill area of Fresno County confirm this species is a cold weather mosquito; peak abundance appeared in the winter months and the winter population was mostly composed of teneral and parous females. The blood meals that were identified were from domestic cattle and horses. The average time period from 1st-instar larvae to adult emergence was 44 days and 47 days respectively for males and females in a natural breeding site.