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Insects and Relatives

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Mosquitoes

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Physical Control Source Reduction Source reduction refers to any method of physically altering a mosquito breeding site to render it unsatisfactory for the completion of the mosquito life cycle. Source reduction projects will vary in size and cost depending on the type, but typically they are the most effective and economical long-term method of mosquito control. A. Sanitation is a continual process of eliminating man-made mosquito breeding locations. To a large extent, the public can be educated to play an integral part in this process. It includes: 1. Removal of water-holding containers, such as tires, to prevent the breeding of mosquitoes, mainly Aedes albopictus and Culexp. quinquefasciatus; removal of debris; elimination of ornamental ponds and swimming pools no longer being used and properly maintained. 2. Maintenance and repair of broken sewer lines, leaking elevator shafts, catch basins, storm water lift stations in some areas and ditches. B. Water management is a method of control where the mosquito source or body of water is altered in such a way that it either is made unsuitable for mosquitoes to complete their life cycle or provides habitat for predators of mosquitoes. 1. Impoundment Management - Impoundments are mosquito-producing marshes around which dikes are constructed to allow water to be pumped onto the marsh surface from the adjacent estuary. This eliminates the egg-laying opportunities of both permanent and floodwater marsh mosquitoes and effectively reduces their populations. 2. Open Marsh Water Management (ditching or runneling) - Shallow ditches are excavated to connect mosquito-producing locations on the marsh surface to deep water habitats (tidal creeks, deep ditches), allowing predator access to mosquito-producing depressions or, conversely, the draining of these locations before adult mosquitoes can emerge. Ditches or runnels usually follow natural drainage depressions and resemble natural channels. 3. Storm Water Retention Structure Management These impoundments are mandated for new construction to handle runoff from the development and prevent flooding of existing waterways. Many of these impoundments become choked with emergent vegetation and begin breeding mosquitoes after a few years. 4. Filling of low-lying depressions to eliminate the potential of standing water. 5. Ditching to promote rapid runoff of rainwater. C. Operational factors 1. Inspectors routinely remove water from containers while advising the homeowner in the process. 2. Other sanitation processes will, at the request of the director, require governmental assistance from the appropriate agency or department, such as state highway department, parish street and drainage department and/or parish health unit. 3. Water management projects are generally very costly and require compliance with federal/state government regulations. Local government can mandate that developers maintain storm water retention structures as a provision of local building and construction guidelines and permitting.