Abstract: A method of controlling mosquito populations is disclosed. The method includes: placing a plurality of ovitraps into an area where it is desired to reduce a mosquito population; filling the ovitraps with water; introducing a defined larvicidal amount of a water conditioning agent comprising cow urine into a given volume of water into the ovitraps to condition the water absent of a separate or additional pesticide; leaving the conditioned water for at least 7 weeks; and monitoring at least one of the ovitrap and the area to determine effectiveness.