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reach the operational stage, an increased investment in surveillance will become
necessary. In a recent survey of U.S. organized mosquito abatement districts,
surveillance, including mapping, inspection, and processing of mosquito collections, accounted for 13-58% of the mosquito control effort and averaged 35%
(NAS, 1976). To this it will be necessary to add surveillance of other components
of the invertebrate fauna in order to avoid disruption of natural systems that
provide a significant degree of control.
8.5. SOURCE REDUCTION
Source reduction is probably the area in which existing knowledge and
technology is most underutilized. The initial cost of source reduction and other
cultural control methods is often cited as a deterrent to their use. Following a
survey of several mosquito control districts in Florida, however, Provost (1977)
reported that the cost of ditching or impounding salt marsh was recovered, on
an average, in 2 or 3 years of savings on larvicide alone. Sarhan et al. (1979),
using an empirical model of mosquito control practices in a California abatement
district, concluded that physical source reduction methods were more efficient
in both the short and long run.
Source reduction alone is usually not adequate, but source reduction has
been a basic component of some of the most successful integrated control programs. Source reduction is not a viable option in some situations because of
environmental considerations. It is particularly inviting in situations where human
activity has already damaged or destroyed the natural ecology, such as by sprawling urbanization or poor agricultural practice. With regard to uncontrolled urbanization, Culex pipiens, a polluted water breeder and the vector of filariasis
in India and of arboviruses in the United States, immediately comes to mind.
Das (1971) states that this species could best be controlled in India by building
more modem sewerage systems than now exist in urban areas and by the use
of such techniques as canalization, interception of seepage, insect proofing of
septic tank ventilation pipes, and installation of manhole covers.
Sharma (1974) reviewed some of the culturally based methods used for
mosquito control in India prior to the DDT era. Deweeding of slow-moving
water channels for An. fluviatilis control, streamlining water flow in irrigation
channels for control of An. culicifacies, sealing of wells for control of An.
stephensi, and the institution of "dry days" in which all domestic and peridomestic
water containers were emptied at least once per week for Ae. aegypti and An.
stephensi control were among the methods that were used effectively, in some
cases in conjunction with Gambusia or limited application of insecticides.
203
reach the operational stage, an increased investment in surveillance will become
necessary. In a recent survey of U.S. organized mosquito abatement districts,
surveillance, including mapping, inspection, and processing of mosquito collections, accounted for 13-58% of the mosquito control effort and averaged 35%
(NAS, 1976). To this it will be necessary to add surveillance of other components
of the invertebrate fauna in order to avoid disruption of natural systems that
provide a significant degree of control.
8.5. SOURCE REDUCTION
Source reduction is probably the area in which existing knowledge and
technology is most underutilized. The initial cost of source reduction and other
cultural control methods is often cited as a deterrent to their use. Following a
survey of several mosquito control districts in Florida, however, Provost (1977)
reported that the cost of ditching or impounding salt marsh was recovered, on
an average, in 2 or 3 years of savings on larvicide alone. Sarhan et al. (1979),
using an empirical model of mosquito control practices in a California abatement
district, concluded that physical source reduction methods were more efficient
in both the short and long run.
Source reduction alone is usually not adequate, but source reduction has
been a basic component of some of the most successful integrated control programs. Source reduction is not a viable option in some situations because of
environmental considerations. It is particularly inviting in situations where human
activity has already damaged or destroyed the natural ecology, such as by sprawling urbanization or poor agricultural practice. With regard to uncontrolled urbanization, Culex pipiens, a polluted water breeder and the vector of filariasis
in India and of arboviruses in the United States, immediately comes to mind.
Das (1971) states that this species could best be controlled in India by building
more modem sewerage systems than now exist in urban areas and by the use
of such techniques as canalization, interception of seepage, insect proofing of
septic tank ventilation pipes, and installation of manhole covers.
Sharma (1974) reviewed some of the culturally based methods used for
mosquito control in India prior to the DDT era. Deweeding of slow-moving
water channels for An. fluviatilis control, streamlining water flow in irrigation
channels for control of An. culicifacies, sealing of wells for control of An.
stephensi, and the institution of "dry days" in which all domestic and peridomestic
water containers were emptied at least once per week for Ae. aegypti and An.
stephensi control were among the methods that were used effectively, in some
cases in conjunction with Gambusia or limited application of insecticides.