Mosquito Facts - 33 Things You Didn't Know About Mosquitoes
A bug is born
- Mosquito is Spanish for“little fly.” The word reportedly originated in the early 16th century. In Africa, mosquitoes are called “Mozzies”.
- There are more than 3,500 species of mosquitoes. About 175 of them are found in the United States, with the Anophelesquadrimaculatus, Culex pipiens, and Aedes aegypti (Asian tiger mosquito) among the most common. The Anopheles is a malaria carrier, and the other two are known to spread various forms of encephalitis.
- West Virginia has the fewest species of mosquitoes. There are 26 in the mountainous state, while Texas has the most with 85. Florida is a close second with 80 identified species.
- Only female mosquitoes bite people. Both male and female feed mainly on fruit and plant nectar, but the female also needs the protein in blood to help her eggs develop. Once she's had her fill of blood, she'll rest a couple of days before laying her eggs.
- Mosquitoes don't have teeth. The females “bite” with a long, pointed mouthpart called a proboscis. They use the serrated proboscis to pierce the skin and locate a capillary, then draw blood through one of two tubes.
- A mosquito can drink up to three times its weight in blood. Don't worry, though. It would take about 1.2 million bites to drain all the blood from your body.
- Female mosquitoes can lay up to 300 eggs at a time. Usually, the eggs are deposited in clusters – called rafts – on the surface of stagnant water, or they are laid in areas that flood regularly. Eggs can hatch in as little as an inch of standing water. Females will lay eggs up to three times before they die.
- Mosquitoes spend their first 10 days in water. Water is necessary for the eggs to hatch into larvae, called wigglers. Wigglers feed on organic matter in stagnant water and breathe oxygen from the surface. They develop into pupae, which do not feed and are partially encased in cocoons. Over several days, the pupae change into adult mosquitoes.
- Mosquitoes hibernate. They are cold-blooded and prefer temperatures over 80 degrees. At temperatures less than 50 degrees, they shut down for the winter. The adult females of some species find holes where they wait for warmer weather, while others lay their eggs in freezing water and die. The eggs keep until the temperatures rise, and they can hatch.
- The average mosquito lifespan is less than two months. Males have the shortest lives, usually 10 days or less, and females can live about six to eight weeks, under ideal conditions. The females lay eggs about every three days during that time. Females of species that hibernate may live up to six months.
The bloodsucker anatomy and behavior
- Mosquitoes have six legs. They also have a head, thorax and abdomen. On the head are two large compound eyes, two ocelli (simple eyes), two antennae and a proboscis. Two large, scaled wings sprout from the thorax.
- Midges and crane flies are often mistaken for mosquitoes. Biting midges are smaller, have shorter wings and tend to feed in swarms. Mosquito traps often attract and kill biting midges. Meanwhile, crane flies are much larger than mosquitoes – up to 1 ½ inches long in some cases – and do not bite.
- Male mosquitoes locate females by the sound of their wings. Females can beat their wings up to 500 times per second, and the males pick out the higher frequency of those beats when seeking a mate.
- Mosquitoes can't fly very far or very fast. Most mosquitoes can fly no more than about one to three miles, and often stay within several hundred feet of where they were hatched. However, a few salt marsh species can travel up to 40 miles. The top speed for a mosquito is about 1.5 miles per hour.
- Mosquitoes generally fly below 25 feet. However, some species have also been found at extraordinary heights, including 8,000 feet up in the Himalayas.
- Mosquitoes can smell human breath. They have receptors on their antennae that detect the carbon dioxide released when we exhale. Those plumes of CO2 rise into the air, acting as trails that the mosquitoes follow to find the source.
- Sweat helps mosquitoes choose their victims. Our skin produces more than 340 chemical odors, and some of them smell like dinner to mosquitoes. They are fond of octenol, a chemical released in sweat, as well as cholesterol, folic acid, certain bacteria, skin lotions, and perfume.
- Body heat marks the target. Mosquitoes use heat sensors around their mouthparts to detect the warmth of your body – actually, the blood inside it – then land on you and locate the best capillaries for tapping.
- Mosquitoes feed day and night. Some species, like the Aedes are daytime biters, while others, like Culex, start biting at dusk and continue a few hours into dark.
The trouble with mosquitoes
- Mosquitoes have been around since the Jurassic period. That makes them about 210 million years old. They've been mentioned throughout history, including in the works of Aristotle around 300 B.C. and in writings by Sidonius Apollinaris in 467 B.C.
- The bumps from mosquito bites are caused by saliva. While one tube in the proboscis draws blood, a second pumps in saliva containing a mild painkiller and an anti-coagulant. Most people have minor allergic reactions to the saliva, causing the area around the bite to swell and itch.
- Malaria is caused by a parasite that lives in mosquitoes. The parasite gets into mosquito saliva and is passed on when the insect bites someone. West Nile and other viruses are passed the same way. Mosquitoes can also carry and pass on canine heartworm.
- West Nile virus came to the U.S.in 1999. Scientists first identified it in a feverish woman in Uganda – the West Nile district – in 1937. There were large outbreaks of the virus reported in Israel, South Africa, and Romania up through the late '90s. The virus first appeared in the United States in 1999 with an epidemic in New York.
- Mosquitoes do not transmit HIV. The virus that causes AIDS does not replicate in mosquitoes and is actually digested in their stomachs, so it's broken down without being passed on.
- Mosquitoes are considered the deadliest “animal” in the world. The Anopheles mosquito, in particular, is dangerous because it transmits malaria, which kills more than one million people every year, primarily in Africa. Alexander the Great is believed to have died of malaria in 323 B.C.
Keeping them away from you
- DEET is considered the 'gold standard' of mosquito repellents. Endorsed by the Centers for Disease Control (CDC), DEET doesn't mask the smell of the host or jam the insect's senses - mosquitoes simply don't like it because it smells bad to them. A product containing 10 percent DEET can protect you for up to 90 minutes. Two other repellents, picaridin and lemon-eucalyptus oil, have also proven effective and are now recommended by the CDC.
- Bacteria can be used to kill mosquito larvae. Bacillus thuringiensis israelensis (Bti) is a commercially-produced bacteria, sold in pellet and powder form, that can be laced into water where larvae live. It produces proteins that turn into toxins after the larvae eat it.
- Dark clothing attracts mosquitoes. Remember, they are drawn to heat and darker clothes retain more heat than light-colored clothing.
- Insecticides work, but only in the short term. Permethrin, one of the most common chemicals used by local mosquito control programs, kills mosquitoes on contact by disrupting their central nervous systems. However, eggs and larvae often are not affected. Once the insecticide dissipates, mosquitoes can return.
- Bats do not eat mosquitoes. At least, not very many of them. Mosquitoes make up less than 1 percent of a bat's diet. And purple martins, a bird popularly believed to be a mosquito predator, eat very few mosquitoes. They prefer dragonflies and other insects.
- The two main mosquito predators are fish and dragonflies. Gambusia, or mosquitofish, feed on mosquito larvae and are used all over the world to help control mosquito populations. Dragonfly larvae, called nymphs, eat mosquito larvae, and adult dragonflies prey on adult mosquitoes. Some towns in Maine release dragonflies every summer as a natural form of mosquito control.
- Mosquito traps can kill thousands of mosquitoes in a single night. One study conducted by public health researchers in Australia found that a Mega Catch trap caught and killed more than 44,000 female mosquitoes from 17 species in less than two weeks.
- Bug zappers are useless against mosquitoes. Studies have shown that less than 1 percent of the insects killed by zappers are mosquitoes or other biting insects. The devices attract and kill beneficial or harmless insects, like moths, and have no effect on the overall mosquito population. Electronic repellers have also proven ineffective in scientific testing.
Mosquito Life Cycle
Birth of a bloodsucker: A Mosquito's Life
If there's anything good about mosquitoes, it's that they don't live very long. The entire mosquito life cycle can be counted in days.Once they emerge from their pupal cocoons and take flight, male mosquitoes last less than a week, the females maybe a couple of months, and that's only with ideal conditions.
The bad news is that they are an extremely hardy type of insect. According to the University of California-Davis Mosquito Research Program, mosquitoes have been around for at least 210 million years.
They don't travel much, typically not more than a mile from the place where they were hatched, and their sole purpose seems to be laying more eggs to make more mosquitoes. A female can produce up to 500 eggs before she finally dies.
And here's a creepy little bit of information: Your blood helps mosquitoes perpetuate the species, and not in the way you probably think. But more about that later on.
Right now, let's start with eggs, the first of four stages in the mosquito life cycle.
That's not a speck of dirt, it's a raft of mosquito eggs
You've probably seen the TV news segments telling you to never, ever leave standing water around your yard because it can become a breeding ground for mosquitoes.The reason for the warning is that mosquito eggs require water in order to develop. Almost any kind will do, from stagnant rain water to the condensation found inside an old tire, as long as the water is not likely to be disturbed for a week or two.
There are about 2,500 species of mosquitoes throughout the world, and roughly 150 of them can be found in the United States. The most common is the Culex pipiens.
The female mosquitoes of Culex and most other species lay their eggs in batches of 50 to 100, often in tiny clumps about a quarter-inch long that float together on the surface of the water like a raft. They make those deposits on water that's collected in tree holes, ditches, even your dog's water dish.
However, some species will lay mosquito eggs on moist, often-flooded soil in anticipation of the next rise in water. Those eggs can survive winter, waiting for spring or summer rains to cover them over.
Females usually deposit their eggs at night, and can lay them about every third night, up to three times.
Entomologists at Oklahoma State University report that the eggs are white when first deposited, then darken to near black within a day. They will hatch in one to three days, depending on the temperature. Eggs left on moist soil can last for up to a year, until the ground is flooded again, before hatching.
When the eggs hatch, the mosquito larvae come out.
Mosquito larvae wiggling all around
This is the baby stage for mosquitoes.The larvae are aquatic creatures that feed on algae, bacteria and other microorganisms in the water. Certain mosquito species will even eat each other. They spend most of their time hanging upside down at the surface, sucking in oxygen from breathing tubes located in their tails.
They're often called “wigglers” because that's how they move in the water, propelling themselves with a frantic twitching motion. At this stage, a mosquito larva is vulnerable to predators such as fish and birds, as well as other mosquito larvae.
The New South Wales Department of Natural Resources in Australia describes them as “hairy maggots with siphons,” covered on the lower half by a cocoon.
Because mosquitoes are cold-blooded and rely on external heat sources to warm their bodies, development depends on the temperature. The warmer it is, the faster the mosquito larvae will grow.
Most larvae develop over about a week or so, shedding their skins – known as molting – four times on the way to becoming mosquito pupae. The molting stages are call instars. By the fourth one, each one mosquito larva is almost a quarter-inch long.
Mosquito pupae rest up for the big debut
The mosquito pupae – called “tumblers” – do not feed. In fact, they don't do much of anything except swim around in the water. Think of this as the teenage stage of the mosquito life cycle.They have short, curved bodies with a large head at one end and flippers for swimming at the other. They are lighter than water, so they live at the surface and, like the larvae, they must take in oxygen from time to time through two breathing tubes known as “trumpets.”
When disturbed, mosquito pupae tumble down to the safety of deeper water and eventually float back to the surface. Again, like the larvae, they are vulnerable to birds and fish. They're also vulnerable to people. Just put a little bit of an oily substance in the water, and a mosquito pupa will be unable to break through to get oxygen.
Otherwise, inside their cocoons, they are developing into those flying insects we all hate. It can take up to four days, depending on the temperature of the water. Once the pupal tissue has developed into adult mosquito form, the adult uses air pressure to split the cocoon and emerge.
The new mosquitoes will rest on the surface – which is one reason eggs are deposited in still water – until their wings dry out and their bodies harden.
Then, they take off.
All grown up and looking for a mosquito mate
Adult mosquitoes are made up of a head with two large compound eyes, a thorax, a pair of scaled wings and six jointed legs. They also have antennae and a proboscis.Mosquitoes, both male and female, come out of the cocoon with two things in mind. They want to breed, and they want to feed, in just about that order.
Adult mosquitoes mate within the first few days after emerging. The male mosquitoes sometimes have to wait for about a day for their reproductive parts to fully develop. They locate females by listening for the sounds of their wings, which run about 250-500 beats per minute. The mosquitoes join, and the males pass sperm to the females, perpetuating the mosquito life cycle.
Once their job is done, male mosquitoes live three to five days. The females tend to mate only once, but live considerably longer, depending on how much warmth and moisture is in their environment. Under ideal conditions, they may last as long as a month or two.
Of course, they have plenty of predators to contend with. Bats and birds feed on mosquitoes, communities spray pesticides to kill them and homeowners use mosquito traps to attract and dispose of them.
The mosquitoes often stay within a short distance of where they emerged from their cocoons, although some species are capable of flying five miles or more. Slow fliers – about 1 mph – and easily dispersed by wind, they prefer to stay close to the ground.
Female mosquitoes on the hunt for blood
Mosquitoes generally feed on plant nectar and fruit juice. Male mosquitoes do not take blood, so when you feel a mosquito plunge into your skin and start siphoning your blood, you can bet it is a female, every time.Typically, female mosquitoes start hunting as the sun goes down and will continue a few hours into the night, searching for any warm-blooded creature, such as people, dogs, cats, birds, and wildlife.
Carbon dioxide – which we exhale – and lactic acid from our sweat combine to make us smell like a mosquito buffet. The insects can pick up the scent from 100 feet, and they can also see us moving and feel our body heat.
They use a serrated proboscis to pierce the skin and inject an anti-coagulant to keep the blood flowing and a mild painkiller, apparently to help them escape detection by their prey. The female mosquito will insert the proboscis into a capillary and withdraw as much blood as she can, up to three times her body weight.
If you are bitten by a mosquito, another thing you can assume is that you have just become a proud new parent, in a way. While female mosquitoes need nectar for nourishment, they also need protein to develop their eggs. That protein comes from your blood.
Once they've gotten blood, the mosquitoes fly away to a warm, damp place to rest and wait for their eggs to develop. That takes up to five days. The females lay their eggs, and then move on to the next blood meal to feed the next batch of eggs.
Female mosquitoes can lay a set of up to 100 eggs about every third night after mating only once. They typically lay as many as three sets before dying.
Those eggs eventually hatch, and the whole mosquito life cycle starts over again.