Control The Butte County Constraints Freeborni Life Cycle & Vector Control District Anopheles The overwintering Anopheles freeborni Egg stage Since 1948 An adult female females are not easily controlled during Freeborni mosquito can lay the cool weather months. The District The District covers over 1600 square approximately 100-400 miles, and includes all of Butte County, usually cannot fog for mosquitoes in the eggs which float on the winter and early spring months due to its surface of the water, or except the small areas served by ineffectiveness compared to the warmer eggs may be laid singly on the surface of the Durham and Oroville Mosquito spring and summer months. the water. Within 2-3 days the eggs hatch Abatement Districts, which were into larvae. formed earlier. The District also includes Certain conditions have to be met the Hamilton City area of Glenn County. in order to effectively control adult Larval stage In April of 1994, “Vector Control” was mosquitoes. During the warmer months Larvae can be found added to the District name to reflect the District sprays for mosquitoes before close to the surface the additional disease surveillance and of the water where the sun rises in the mornings and after information now provided. it has set in the evenings. This is not they breathe and feed. usually possible in January, February, or Larvae are found in a wide variety of standing water sources March since the temperature is not warm our Mission including rice fields, ditches, ponds, and enough to spray during those times. horse troughs. Larvae shed their skin The mission of BCMVCD is primarily to suppress mosquito-transmitted The overwintering mosquitoes are four times during the next several days or weeks, finally changing into a . disease and to also reduce the usually most active during sunlight annoyance levels of mosquitoes and hours. The District does not spray Pupal stage diseases associated with ticks, fleas and during sunlight hours due to improper In the pupal stage, the other vectors through environmentally weather conditions such as the lack of mosquito grows inside compatible control practices and public an inversion layer, UV rays reducing the of a cocoon-like shell. education. pesticides effectiveness, and the risks to Once fully developed, non-target beneficial . the pupal skin splits and the mosquito emerges as an adult.

Adult stage The newly emerged adult mosquito rests on the surface of the water until it is strong enough to . Female mosquitoes require a blood meal to lay eggs. Male mosquitoes do not feed on 5117 Larkin Road blood. Female mosquitoes are attracted Oroville, CA 95965 by heat and carbon dioxide to hosts (530) 533-6038 such as humans, mammals, and birds. or Diseases are transmitted when female (530) 342-7350 mosquitoes feed on an infected host and then feed on an uninfected host. www.BCMVCD.com Mosquitoes ABOUT Anopheles

Bugging You? freeborni TREES

The later parts of summer and early fall While cold winter weather kills most IRRIGATED PASTURE bring extremely high populations of the species of adult mosquitoes, the adult Western mosquito (Anopheles female Anopheles freeborni hibernates SPRING Adult Anopheles move to freeborni) to most of Butte County and during these months. agricultural areas to lay eggs Hamilton City. The majority of these In the fall these mosquitoes disperse URBAN RIPARIAN mosquitoes are bred in agricultural lands RICE FIELD PARK CREEK AREA throughout the west and south areas of several miles from their breeding sources AREAS to seek shelter in protected places, such the county. UNDERGROUND as houses and outbuildings. They are STORMWATER STRUCTURE This mosquito is medium sized, brown often a nuisance at this time. UNDER to tan in color, with long legs, and EAVES On warm, sunny days, only screened WATER dark spots on the wings. It is a very WINTER windows and doors should be opened. Adult Anopheles move to aggressive mosquito and is readily found towns to find overwintering sites in and amongst homes, barns, yards, and Keep screens in good repair. If mosquitoes do get inside your house, they may be vegetative areas. This pest also has the CULVERT found resting on walls, under sinks, in OR UNDER ability to fly long distances in one night, BRIDGE HEDGES DECKS allowing it to fly from its rural breeding closets, etc. site to urban areas. This mosquito is A warming trend in January, February commonly found throughout most of or March sounds a wakeup call to these California and is a severe pest in rice mosquitoes. They are extremely hungry CATCH BASIN growing areas. and are looking for a blood meal that will nourish their developing eggs.

Biting females are most bothersome How Can You Protect during the afternoons and early evenings. Yourself from Mosquitoes? Fortunately, the problem usually lasts only as long as the warm days persist. Where they breed Minimize outdoor activities at Their breeding patterns and life cycle are slightly different from other mosquitoes. Anopheles dawn and dusk when mosquitoes Adult behavior freeborni prefer standing water that is open and sunlit with vegetation and algae present. Such are most active. The adult population reaches its peak in sources include rice fields, creek isolations, ponds, swampy areas, stream edges, and drains. August. Females hibernate during the Drain any standing water around winter months and disperse from their Can these mosquitoes transmit disease? your house. hibernating sites in February or March. The Western Malaria Mosquito is considered unlikely to transmit West Nile virus. These Females will readily enter houses during mosquitoes historically transmitted malaria and were involved in the malaria epidemics Wear long sleeves and pants at peak activity time. Males do not bite but during the late 1800’s and early 1900’s in northern California. dusk and dawn. feed on nectar and plant juices. Although malaria is not currently a concern in California, the potential for disease Use an repellent approved transmission exists if malaria is reintroduced through an imported human case. The District by the EPA and recommended by works closely with state and local health departments to monitor new and reemerging vector- the CDC. borne diseases.