Mosquito Bytes
Mosquitoes
are insects belonging to the order Diptera, the True Flies. Like all True Flies, they have two wings, but unlike
other flies, their wings have scales and their mouthparts (in female mosquitoes) form a long piercing-sucking proboscis.
Males differ from females by having feathery antennae and mouthparts not suitable for piercing skin. Nectar is
their principal food source.
The Spanish called the mosquitoes, "musketas," and the native Hispanic Americans
called them "zancudos." "Mosquito" is a Spanish or Portuguese word meaning "little fly"
while "zancudos," a Spanish word, means "long-legged." The use of the word "mosquito"
is apparently of North American origin and dates back to about 1583.
Mosquitoes can be an annoying, serious problem in man's domain. They interfere with work
and spoil hours of leisure time. Their attacks on farm animals can cause loss of weight and decreased milk production.
Some mosquitoes are capable of transmitting diseases such as malaria, yellow fever, dengue, filariasus and encephalitis
The mosquito goes through four separate and distinct stages of its life cycle: Egg, Larva,
Pupa, and Adult. Each of these stages can be easily recognized by its special appearance.
Egg : Eggs are laid one at a time and they float on the surface of the water. In the case of Culex and Culiseta
species, the eggs are stuck together in rafts of 200 or more. Anopheles and Aedes species do not make egg rafts
but lay their eggs separately. Culex, Culiseta, and Anopheles lay their eggs on water while Aedes lay their eggs
on damp soil that will be flooded by water. Most eggs hatch into larvae within 48 hours. Water is a necessary part
of their habitat.
Larva : The larva (larvae - plural) lives in the water and comes to the surface to breathe. Larvae shed (molt)
their skins four times, growing larger after each molting. Most larvae have siphon tubes for breathing and hang
from the water surface. Anopheles larvae do not have a siphon and lay parallel to the water surface to get a supply
of oxygen through a breathing opening. The larvae feed on micro-organisms and organic matter in the water. On the
fourth molt the larva changes into a pupa.
Pupa: The pupal stage is a resting, non-feeding stage. This is the time the mosquito turns into an adult. It takes
about two days before the adult is fully developed. When development is complete, the pupal skin splits and the
mosquito emerges as an adult.
Adult: The newly emerged adult rests on the surface of the water for a short time to allow itself to dry and all
its body parts to harden. The wings have to spread out and dry properly before it can fly.
The egg, larva and pupa stages depend on temperature and species characteristics to determine how long they take
for development. For instance, Culex tarsalis , a common California, USA mosquito, might go through its life cycle
in 14 days at 70 F and take only 10 days at 80 F. Also, some species have naturally adapted to go through their
entire life cycle in as little as four days or as long as one month.
Mosquitoes Need Water: All mosquitoes have four stages of development-egg, larva, pupa, and adult-and spend their
larval and pupal stages in water. The females of some mosquito species deposit eggs on moist surfaces, such as
mud or fallen leaves, that may be near water but dry. Later, rain or high tides reflood these surfaces and stimulate
the eggs to hatch into larvae. The females of other species deposit their eggs directly on the surface of still
water in such places as ditches, street catch basins, tire tracks, streams that are drying up, and fields or excavations
that hold water for some time. This water is often stagnant and close to the home in discarded tires, ornamental
pools, unused wading and swimming pools, tin cans, bird baths, plant saucers, and even gutters and flat roofs.
The eggs deposited on such waters soon hatch into larvae. In the hot summer months, larvae grow rapidly, become
pupae, and emerge one week later as flying adult mosquitoes. A few important spring species have only one generation
per year. However, most species have many generations per year, and their rapid increase in numbers becomes a problem.
Only the Female Can Bite: When adult mosquitoes emerge from the aquatic stages, they mate, and the
female seeks a blood meal to obtain the protein necessary for the development of her eggs. The females of a few
species may produce a first batch of eggs without this first blood meal. After a blood meal is digested and the
eggs are laid, the female mosquito again seeks a blood meal to produce a second batch of eggs. Depending on her
stamina and the weather, she may repeat this process many times without mating again. The male mosquito does not
take a blood meal, but may feed on plant nectar. He lives for only a short time after mating.
Winter Survival Is Important: Most mosquito species survive the winter, or overwinter, in the egg stage, awaiting
the spring thaw, when waters warm and the eggs hatch. A few important species spend the winter as adult, mated
females, resting in protected, cool locations, such as cellars, sewers, crawl spaces, and well pits. With warm
spring days, these females seek a blood meal and begin the cycle again. Only a few species can overwinter as larvae.
Mosquitoes Can Transmit Disease: Mosquito-borne diseases, such as malaria and yellow fever, have plagued civilization
for thousands of years. Organized mosquito control in the United States has greatly reduced the incidence of these
diseases. However, there are still a few diseases that mosquitoes in New, Jersey can transmit, including Eastern
Equine Encephalitis and St. Louis Encephalitis. The frequency and extent of these diseases depend on a complex
series of factors.
Reduce the Amount of Standing Water: The most efficient method of controlling mosquitoes is by reducing
the availability of water suitable for larval and pupal growth. Large lakes, ponds, and streams that have waves,
contain mosquito-eating fish, and lack aquatic vegetation around their edges do not contain mosquitoes; mosquitoes
thrive in smaller bodies of water in protected places. Examine your home and neighborhood and take the following
precautions:
- Dispose of unwanted tin cans and tires.
- Clean clogged roof gutters and drain flat roofs.
- Flush sump-pump pits weekly.
- Stock ornamental pools with fish.
- Change water in birdbaths, fountains, and troughs twice a week.
- Clean and chlorinate swimming pools; when not regularly used, they should be emptied.
- Turn over unused wading pools and other containers that tend to collect rainwater.
- Cover containers tightly with window screen or plastic when storing rainwater for garden
use during drought periods.
Mosquito
http://www.britannica.com/bcom/eb/article/2/0,5716,55272+1+53915,00.html
Menacing Mosquitoes
http://whyfiles.news.wisc.edu/016skeeter/index.html
The Buzz on
Mosquitoes
http://washingtonpost.com/wp-dyn/kids/archive/A35304-2000Jul24.html
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