Biological control of mosquito populations: An applied aspect of pest control by means of natural enemies

Abstract

Mosquitoes were recognized as a health and nuisance problem only in the last century. Since mosquito oviposition sites were initially associated with the expansion of human settlements, which as a rule is done by building actions of poor economies, the biological control became a necessity. Even with the development of chemical industry, the preparation of synthetic formulations of insecticides is environmentally hostile and ecologically unsafe since the main side effect of the application is the extinction of natural enemies of mosquitoes such as odonates, beetles, fishes and hemipterans in water pools apart from the induced resistance in a short time. The advancement of biological knowledge made available many new controlling methods of mosquito populations though substantially more expensive than synthetic insecticides. The most important of them is the set of semiochemicals (natural products) associated with the classical biological control by means of predators. Many investigations have proven that predators are able to control mosquitoes in ecosystems of variable size, nutrients and prey densities. Semiochemicals are employed in many aspects predation. Prey detection, oviposition site selection, chemical crypsis, kairomonal confusion is among the ways that predators and their prey mosquitoes are using to affect the outcome of predation. Microbials as killing agents, are extensively used in projects for mosquito control in order to minimize the environmental side effects of insecticides. However, they fail to eradicate pest populations. In the present report is described an integrated system for the control of mosquitoes from experience gained in Mediterranean areas of application. The control system is able to incorporate any future developments in mosquito population management such as new introductions or releases from rearing of predators, new genetic methods or inexpensive repellents and oviposition deterrents.