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HomeMy WebLinkAboutSS3 - Orange County Vector Control District7 * 160 GE CpL� O � WHAT IS THE ORANGE COUNTY VECTOR CONTROL DISTRICT? 00A oM The Orange County Vector Control District is a special district formed in 1947. It is supported by a small per parcel fee and property tax that is about the equivalent to the cost of a can of insect spray. The District functions under the provisions of the California State Health and Safety Code (Division 3, Chapter 5, Article 2, Sections 2210 - 2226). The District is governed by a Board of Trustees composed of 32 members, each appointed by a city within the District, and one Board member representing the unincorporated area of the County -at- Large. The Trustees are appointed for either a two or four year term. The Trustees serve without pay, but are compensated in -lieu of expenses at $50 per monthly meeting. The Board of Trustees meets regularly on the third Thursday of each month at 3:30 P.M. at the District headquarters at 13001 Garden Grove Boulevard, Garden Grove. The principal mission of the District is management and control of several species of vector organisms (animals, such as insects, that can transmit disease or cause injury to humans) and to maintain a surveillance and detection program for the diseases they carry. It is important to distinguish between vectors and other kinds of pests that may be of agricultural importance (medfly, gopher, etc.) or structural (termites, silverfish, flour moths, etc.). None of the foregoing can transmit disease and thus are not vectors. The vectors that the District maintains year - round operational control programs on are mosquitoes, rats, and flies. Other less common problems such as scorpions, ticks, and Africanized honey bees are dealt with as the need dictates. Larger animals, such as coyotes, skunks, raccoons, and venomous reptiles are traditionally handled by city or county animal control departments. Orange County has changed from a largely agricultural and rural area to a prosperous urban area in just three decades. With this transition, mosquito breeding habitats have also diversified. The pastures, dairy farms, truck gardens, and orchards of yesterday are now the housing developments, resorts, tourist attractions, and commercial operations for which the County has become famous. Many of the mosquito breeding sources are directly related to the County's urbanization. Flood channels, off - street drains, street gutters, catch basins, ornamental fish ponds, and neglected swimming pools have replaced the rural mosquito habitat of 30 years ago. In the District's approach to mosquito control, four elements of Integrated Pest Management are used: (1) physical, (2) biological, (3) chemical, and (4) public education. Source reduction, sometimes called physical control, is the first element of mosquito control. This method involves reducing or eliminating an aquatic mosquito breeding source through drainage or other means of eliminating the water. Sometimes this is as simple an operation as emptying out a backyard wheelbarrow filled with rainwater. Biological control involves the use of mosquito fish (Gambusia affinis), where possible. These fish are reared at District headquarters and planted in those aquatic mosquito breeding sources where the quality of the water is sufficiently high to support them. The most widely used is chemical control employing larvicide oils, biorational pesticides, such as Bti, and the juvenile hormone, methoprene, with some limited use of organophosphates. Most of these chemicals are directed toward the larval stage of the mosquito, although some selective spraying for adult mosquitoes is done. The fourth method of control is public education. The District pursues a vigorous program of public educational activities involving public and private schools, homeowners associations, civic organizations, electronic and print media, and other avenues of information dissemination. The combination of these four elements, used where appropriate, has brought mosquito -borne disease to a very low level. Of the 18 species of mosquitoes existing in _r Orange County, several are potential disease carriers or significant biting pests. The most significant potential vector species are Culex tarsalis, the primary encephalitis vector in the west, and Anopheles hermsi, the southern California malaria mosquito. Canine heartworm is a concern in dogs in Orange County, although it is unclear which species of mosquito is the vector. There are several species of filth flies in Orange County. The vast majority of flies are produced by human carelessness. Trash cans that are not cleaned regularly, domestic animal waste, poorly managed compost piles, and other decomposing organic material can produce sizable populations of flies. The District attempts to prevent fly production through public education and regular inspection of those operations which by their nature are capable of generating large numbers of adult flies. The District does a limited amount of adulticiding when the population of flies is great enough to present a clear public health problem, but this is done very selectively. The roof rat, Rattus rattus, is the majorproblem species in Orange County. They have adapted readily to the lush residential backyards where many fruit trees still exist providing food for the rats. They nest mainly in Algerian ivy, bougainvillea, untrimmed palm trees, and other dense vegetation common in southern California. The Norway rat, Rattus norvegicus, is not a significant problem in Orange County. This species is confined to several ocean jetty structures and other isolated habitats along the coast. Norway rats are relatively poor climbers. They favor higher protein food sources, such as meat scraps, garbage, cereals, and seafood. These rodents burrow and establish their nests nearer ground level than the roof rat. The District approaches roof rat control in an integrated way, much the same as it does with other vector species. One of the most important elements in the program is the motivation of homeowners to reduce or eliminate both nesting harborage such as ivy, bougainvillea, and untrimmed palm trees, along with sources of food and water from their properties. These procedures are augmented by selective placement of anticoagulantroden ticides. The District currently uses one -half pound paraffin -based rodenticide blocks containing an anticoagulant ingredient mixed with cornmeal, sugar, and dyes. These bait blocks are placed on properties where rats feed or find harborage. At the same time, adjoining properties are inspected and rat prevention/ control recommendations are made to the property owners. The District has taken a conservative approach to the use of rodenticides in an attempt to forestall resistance to the material by the roof rat population in Orange County. The District receives more than 9,000 requests for rat control assistance every year. The District also carries out vector -bome disease surveillance in Orange County, including detection of bubonic plague and several strains of mosquito -bome encephalitis. This is done routinely throughout the year. In 1984, an epidemic of mosquito -bome St. Louis encephalitis occurred in the southern California area. Of the 26 confirmed human cases, 6 of these occurred in Orange County. The District is also involved in research in tick -bome Lyme disease, murine typhus (flea - bome), and hantavirus. The District works closely with other agencies to accomplish its mission. Among those at the federal level are the U.S. Fish and Wildlife Services, Environmental Protection Agency, and the Centers for Disease Control. At the state level, the Department of Health Services, Department of Pesticide Regulation, and the University of California are all important contacts. Locally, county departments of planning, health, flood control, and agriculture are dealt with routinely. City planning and code enforcement departments play important roles in accomplishing the District's mission, The District is a member of the Mosquito and Vector Control Association of California ( MVCAC), a nonprofit organization created to unite California vector control agencies in promoting research, annual education conferences, workshops, and training sessions for the exchange of technical information. MVCAC also facilitates communication with state legislators and other policy makers. The District is also a member of the statewide Vector Control Joint Powers Agency Insurance Pool. This pool has significantly reduced the cost of workers compensation and liability insurance. ORANGE COUNTY VECTOR CONTROL DISTRICT 13001 Garden Grove Boulevard, Garden Grove. CA 92643 (714) 971 -2421 • 1- 800 - 734.2421 Red Imported Fire Ants (RIFA) General Information The Red Imported Fire Ant, Solenopsis invicta is the most recent of a growing number of pests introduced into Orange County. A native of South America, the Fire Ant was first introduced in the southeastern United States in 1930s, Since that time the ants have found their way across the south, and into Southern California. RIFA "mounds" are very distinctive and easily recognized as a low mat of fine granular soil as much as 18 inches across. Fire Ants commonly settle in turf and frequent mowing keeps ants from forming the larger mounds typically found in the southeast. The greatest threat posed by Fire Ants is their venomous stings. The ants can sting repeatedly which results in a burning, itching sensation that is followed by a raised pustule a few days later. The pustule can last for up to two weeks. RIFA venom is relatively toxic, and potentially lethal to pets, wildlife and sensitized humans. Because of the number and severity of stings delivered by this aggressive species, residents should be aware of the existence of this menace on their property and the potential hazards posed by accidental contact. Fire Ants are also damaging to landscape material as well as agricultural products. Electrical current is a strong attractant for Fire Ants so irrigation controllers, air conditioners and outdoor lighting are all at risk. Description RIFA are small ants that display a wide range of sizes within a single colony. Individual ants can be from '/8 to %. inch long. They have a shiny dark red head and thorax with a dark brown abdomen. They posses a pair of toothed mandibles to grasp the skin before they sting. Fire Ants have two nodes between the abdomen and thorax. The tip of the antennae is a two - segmented club. Rev. 6/12/01 Control The Orange County Fire Ant Authority ( OCFAA) recommends that citizens leave RIFA colonies undisturbed. A call to the Hotline (1-888-4 - FIREANT) will assure prompt, no- charge treatment, not just of the resident's home, but the entire neighborhood. Suspected infestations can also be reported on our website: www.ocfi- eant.com. Improper treatment can cause the infestation to spread and increase the effort required to achieve eradication. The OCFAA uses two baits to eliminate Fire Ants; our first application is with a product containing hydramethylnon, a metabolic inhibitor that results in starvation of the colony. The OCFAA also uses an insect growth regulator, pyriproxyfen that sterilizes the queen, ending the reproduction and replacement of workers, until the colony slowly dies out completely. Both products are safe for humans, pets, and the environment. These products are slow acting, if ants are found indoors or if for some reason citizens are unable to wait several days for results, they should call a licensed pest control operator. Keep in mind a fast acting treatment will likely prolong the infestation in exchange for temporary quick results. In the event a pest control operator is called the OCFAA should still be notified so the surrounding area can be treated to avoid reinfestation. ORANGE COUNTY FIRE ANT AUTHORITY A Division of the Orange County Vector Control District P.O. Box 59, Santa Ana, CA 92702 1- 888- 4- FUtEANT Visit our website at: www.ocfireant.com Summary of Fire Ant Activity in Newport Beach The beach communities of Orange County have, for the most part stayed beyond the RIFA infestation limits. The exceptions have been the larger cities that extend several miles inland or have undergone extensive development lately. The Newport Coast area exposes the city of Newport Beach on both counts. In June of 2000, a RIFA nest was located in Newport Coast; two more were found in August, by October, there were 7 known sites. It is not possible to tell with certainty how or when the ants arrived, but the OCFAA became aware of the threat because of citizens using the CDFA hotline. None of the known colonies in Newport Beach are currently showing any activity. It seems that the prevailing winds in Orange County tend to protect the coastal areas from "fly in" infestation, and the Santa Ana winds are so hot and dry that they are probably ineffective for ant dispersal. These are just trends and it should not be assumed that ants are not able to move west under their own power. Newly mated queen ants are attracted to the habitat offered by disturbed soil, so it is possible that they arrived in Newport Coast on their own, drawn by the tremendous disturbance caused by recent development. It is also possible that the fire ants were inadvertently brought there on a landscaping truck, not necessarily to the property they now occupy, but at least to the area. It should be noted that a colony could exist for several months before it is large enough to emerge as a visible mound. The state has implemented several steps to reduce the possibility of ants being moved along with landscape material, but it is entirely possible the ants were introduced before some of these steps were in effect. Newport Coast illustrates the problems we face in much of the more recently developed parts of the county. In addition to the backyards, there are vast areas of slopes and common areas that are irrigated, so they are suitable habitat, but no one visits these areas regularly. Fire ant colonies can flourish undetected under these conditions and, move into backyards, or repopulate areas they have been eliminated from. In addition to mating flights, fire ants can move several hundred feet overland. Citizens helping out by performing the "pest test ", best meet the challenge of detection. The "pest test" not only will locate nests on the property, but also will warn of an ant colony in an adjacent area that would have otherwise gone unnoticed. 4 V O V/ 0 PEN A� �Wy �I �I a s �I 0 PEN CA 0 PEN wo so T U� 0 y \y QW' y y0 � i Q` C~ N N C~ a� U 2 n 0 0 N c� /y 10 NEWPORT BEACH MARSHES Kadane Backbay: Backbay (South) Backbay (North Fresh Water Westbluff Macarthur Marsh and Basin Bonita Canyon Marsh FLOOD CHANNELS AND CREEKS Harbor Cove Basin and creek Upper Big Canyon Harbor Ridge Nature Park Ford Road Creek Bonita Canyon Creek Big Canyon Big Buck Little Buck Harbor View Dam Fashion Island DRAINS AND DITCHES Freshwater "T" Backbay Rd. ditch East Bluff drains Bayview drains * THERE ARE ALSO NUMEROUS AMOUNTS OF UNDERGROUND LOCATIONS.