As mentioned before, traditional electronic bug zappers are usually ineffective against mosquitoes, rendering them useless to a late evening picnic. Some but-zappers however try to solve this problem.
Mosquitoes are attracted to humans because of the carbon dioxide that is emitted through our breath and sweat. Because of this, some mosquito zappers take advantage of this by emitting steady streams of carbon dioxide, Octenol attractant and moisture. This pulls the Mosquitoes into a net where they will dehydrate and die. These devices are usually powered by a propane tank, so no electricity is required. One manufacturer of these products claims that entire mosquito populations collapse in six to eight weeks because egg-laying females are destroyed in these contraptions.
Another device uses a chemical that the manufacturer claims blocks the mosquito's olfactory receptors. The makers of this product say that blocking the insect's ability to "smell" carbon dioxide reduces the number of mosquito landings and bites.
The biggest battle in the war against mosquitoes is getting to the female mosquitoes and their eggs. Since mosquitoes lay eggs in water, the goal is to eliminate all sources of standing water, such as watering cans, old tires, buckets, etc. Cover your rain barrels and if you have a pond, stock it with fish that will eat mosquito larvae.
Commercial pesticides are available that kill both mosquito larvae and adults. Municipalities often spray pesticides, particularly malathion, on a large scale in the spring and summer to eliminate mosquito populations.