|MadSci Network: General Biology|
While it is true that many dragonflies eat mosquitoes it is also true that no plan to increase their numbers is practical. First you need to have a marsh or pond for the dragonflies to breed (also a great place for mosquitoes to breed as well!) Dragonfly nymphs feed on other insects, tadpoles and small fish (this latter habit makes the nymphs pests in fish hatcheries!) For garden pests there are many things (such as raising good nectar producing flowers)you can do to attract beneficial insects, such as parasitic wasps, but mosquitoes are not as easily controlled (keep in mind that millions are eaten by dragonflies, predatory flies, spiders, birds, reptiles and amphibians) by predators to the point where they are not a problem to us at all (although they would be much worse without the predators!) For information on dragonflies try: Silsby, Jill. 2001. Dragonflies of the World. Smithsonian Institution Press, Washington, D.C. 200 pp.
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