CAN WE DO ABOUT MOSQUITOES?
July 8, 2012
are a scourge, especially in years like this one with obnoxiously hot
weather punctuated by sporadic thunderstorms. Consequently, I am often
asked, What can we do to reduce the number of or even eliminate these
itchy nuisances? The following answer from a few years ago applies equally
well this year and may provide a little relief.
followed by warmer than normal temperatures create ideal conditions
for many species of mosquitoes to complete their life cycle and reach
the blood-sucking stage we all despise. More than 3,500 species of mosquitoes
exist, and like many other groups of animals and plants, the highest
diversity is in the tropics. But the temperate zone has its share, and
like other groups of organisms with many species, mosquitoes differ
considerably in their natural history, including one group that does
not even bite people. The basic life cycle of a mosquito, like that
of flies, grasshoppers, and many other insects, starts with the egg,
which becomes a larva, which develops into a pupa before becoming an
adult. Mosquito larvae and pupae are the "wrigglers" seen
flipping around in shallow standing water.
step in reducing the number of mosquitoes around a house is to eliminate
standing water. The problem is that an amount as negligible as that
collected in a dead magnolia leaf, an un-emptied rain gauge, or a low
spot in a house gutter can become a mosquito nursery where eggs are
laid and larvae and pupae thrive. Old tires and tree holes that collect
water are actually preferred egg-laying sites for some mosquitoes. Some
kinds of mosquitoes even lay their eggs on dry soil in depressions that
later fill with water, stimulating the eggs to hatch. Sprinkler systems
that keep grass and shrubs looking nice may provide all the water some
mosquitoes need to start the cycle.
stages last for a few days to a week or more, depending on the species
and on the water temperature. Adult mosquitoes can live for days or
weeks. Only the females suck blood, as part of the reproductive cycle.
The blood is used to provide nourishment to the eggs while they are
in the female's body. When one batch of eggs is laid, she is ready for
another blood meal to get the next batch ready. Male mosquitoes, benign
creatures with no interest in humans, feed on nectar.
attempt to eliminate or reduce mosquito problems in many ways, including
municipal mosquito trucks, backyard mosquito traps, handheld mosquito
foggers, and the numerous insect repellents on the market. The strategy
of one of my daughters is to stand close to her husband when mosquitoes
are around. He apparently attracts all of them, and they no longer find
her as palatable. As a general rule, mosquitoes are attracted to warm
body temperatures, which we all have, and carbon dioxide, which we all
exhale. I know two people whose body temperature runs about a degree
below normal, and they are seldom bitten by mosquitoes while others
around them are.
tactic in the war against mosquitoes, besides swatting the life out
of them when they land on your arm, is to set up a mosquito decoy site.
Put a bowl or glass of water somewhere in your yard, such as on a deck
or porch, and check it daily. If wrigglers are present, a blood-sucking
mosquito laid her eggs a few days earlier. Give the wrigglers a day
or so before you pour the water out on dry ground to kill them. Then
refill the container for the next round. You can enjoy knowing you have
scored a minor victory over one female mosquito and her insidious progeny.
Also, the decoy lets you know that mosquitoes have recently laid their
eggs so the time has come to search for other standing water around
the house. Incidentally, a dab of toothpaste is a quick and effective
way to stop the itching from bites by mosquitoes whose mothers don't
fall for the decoy.
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