Mosquitoes:

The best-known biting insect, mosquitoes make many areas nearly uninhabitable in certain seasons and at certain times of the day. While most are nocturnal, many attack in daytime, or close to sunrise and sunset. They are most common out-of-doors, but many enter houses, especially at night and in the tropics. They seriously disrupt the lives of many animals and birds, aside from human beings, and often carry disease to their victims.

Like most insects, mosquitoes begin with a fertilized egg. Depending on the species, eggs may be laid in a variety of waters, from those of quiet pools (even snow pools), to salt water marshes, to tree holes and gutters. Although eggs may hatch in a few days, under humid conditions eggs of some species may remain viable for several years.

Some Facts About Mosquitoes: 

Why do mosquitoes bite? Only female mosquitoes bite. Female mosquitoes require a blood meal to acquire the protein needed to produce eggs. Females lay multiple batches of eggs during their lifespan, and a new blood meal is needed to produce each batch. Different mosquito species prefer different host species; some mosquitoes will seek blood meals from birds, others from mammals - and some are generalists. The female inserts her needle-like proboscis - a slender, tubular, feeding and sucking organ - under the victim's skin, drawing blood into her abdomen. She will feed until her abdomen is full, unless discovered and brushed away.

Why do mosquitoes seem to bite some people, but not others? This phenomenon is not completely understood. Mosquitoes are attracted by the carbon dioxide that we - and other animals - exhale. They may also be attracted by various odors - perfume, perspiration, lactic acid, detergents - that combine in unique ways to make one victim more attractive than another as a meal. Because dark colors absorb heat and lighter colors tend to reflect heat, mosquitoes also tend to be more attracted to victims dressed in darker clothes. Also, some people react more violently to the bites than others and only appear to be bitten more often.

Why do mosquitoes bites itch and swell? The itching, swelling, and burning from a mosquito bite are actually caused by the body's autoimmune response to the saliva injected by the mosquito when she feeds. This saliva contains anti-coagulating agents that prevent the victim's blood from clotting as it is sucked into the mosquito's abdomen. A bite may take several days to heal and stop itching; treat it with Calamine lotion or a topical anti-itch medication.

Where do mosquitoes breed? Mosquitoes breed in wet, swampy areas, where they lay their eggs. The eggs hatch in the water, and the young mosquitoes spend their pupal stages in the water. Mosquitoes lay eggs in both fresh and polluted water, and seek still waters such as those found in small puddles, ditches, and ponds. Even a small amount of standing water - say, in the bottom of a flower pot - will provide sufficient habitat for mosquito eggs. These eggs usually hatch about 5 days after they are laid. A key factor in mosquito prevention is the elimination of standing water in an area.

What is the average lifespan of a mosquito? Like most insects, mosquitoes are a prime food source for birds, amphibians, and spiders. Between predators and extreme weather events such as drought and harsh rains, most mosquitoes live for an average of about two weeks in their adult form. If they manage to escape predators, females from some mosquito species live to about two to three months of age. Those females who enter adult form late in the season may go into hibernation as cooler weather approaches, and can emerge the following spring to lay eggs. In many species, eggs laid before the onset of cold weather can also survive through a winter, even without water, re-hydrating in spring rains to go through larval, pupal, and adult stages.

How many types of mosquitoes are there? According to the American Mosquito Control Association, there are more than 2500 species of mosquitoes World-wide.

Deer & Horse Flies: 

While not as serious a carrier of disease as mosquitoes, many Tabanids viciously attack both animals and human beings. Most prefer warm seasons and the warmth of the day, but some species are most active at dawn or dusk. While waiting for females, Tabanid males hover in large swarms at "aggregate sites" in relatively open areas. These swarms do not attack, for only females are able to bite.

There are two principal genuses. Tabanus includes the larger black "horse flies", as well as the smaller salt-marsh dwelling "greenheads" and striped horse flies. Equally vicious are the smaller Chrysops or deer flies with multi-colored, cross-banded wings.

Bites are deep and painful, but unless one is allergic the effects will soon pass (if not the memory). Repeated attacks by Tabanids can cause serious blood loss in animals.

Black Flies: 

Especially in Spring and early Summer, swarms of small black flies can make life intolerable. They seldom enter houses, but vacationers and laborers, as well as livestock and wildlife, can be severely affected.

The larvae require running water to feed. To this extent, Black Fly habitat differs from that of Mosquitoes and Deer Flies, since standing water is of no use to them.

Biting occurs mostly during the day, particularly early morning and toward evening. Threatening weather, as before a thunderstorm, intensifies biting. Females target body projections, such as ears, and the lower parts of the body. They are attracted by odors, shapes, and colors - and in common with other biting insects, carbon dioxide. Males do not bite, but on the outlook for females, they often swarm near female targets.

Biting Midges: 

Also known as "no-see-ums", "sandflies", and "punkies", Biting Midges are so small that they can pass through ordinary mosquito netting. The parts of the body attacked vary widely. Some species attack around the head and eyes. Others attack the ankles, often crawling up the body under clothes. Targets soon become aware of a burning sensation, and subsequent welts may itch for days.

Frequently confused with Black Flies, their appearance (aside from size), life cycle, distribution, and habits are quite similar. Any area near water is a good habitat for one or another species. Even more than Black Flies, Biting Midges restrict their attacks largely to daylight hours.

Sand Flies: 

These include any insect of the family Phlebotomidae of the order Diptera. The aquatic larvae live in the inter-tidal zone of coastal beaches, in mud, or in wet organic debris.

Sand flies are of considerable medical importance: around the Mediterranean and in southern Asia, Phlebotomus transmits the pappataci fever virus; and in parts of South America, Africa, and Asia it carries the protozoan parasites causing kala azar, Oriental sore, espundia, and bartonellosis.

The name sand fly is also used for certain species of the black fly and the biting midge. They are often referred to as No-See-Ums because you rarely see them.

Chiggers: 

Chiggers are the parasitic larvae of the harvest mite, Trombicula alfreddugesi. The adults are harmless, but the tiny, six-legged larval stage is parasitic on many animals, including rodents, birds, rabbits, livestock, reptiles, toads, and humans. The biting season is therefore limited to the late summer/early autumn period when the larvae are active.

Chiggers occur in several parts of the world including the southern United States and do not normally transmit disease. However, in parts of Asia they are known to carry "scrub typhus".

They are normally found in brush and tall grassy areas, especially where small rodents are abundant. Females lay eggs on the ground in groups of up to 400, picking damp but well drained sites. They may be particularly abundant near river banks and under trees or bushes.

The larval chigger is an active creature that moves to the tip of grasses and fallen leaves to wait for and grab onto a passing host. Once on its host, the chigger usually moves about until it reaches a place where it is somewhat protected, such as around ankles, under socks, waistline, under belts and elastic bands of underwear etc.

Chiggers do not burrow into the skin, but they do pierce the skin, (often around a hair follicle) and after secreting digestive enzymes in their saliva, they suck up the liquefied host tissues. The rash and intense itching associated with chigger bites is an allergic reaction to their salivary secretions.

After a larva is fully fed days, it drops off the host, leaving a red welt with a white, hard central area on the skin that itches severely and may later develop into dermatitis. Welts, swelling, itching, or fever will usually develop three to six hours after exposure and may last for weeks depending upon the sensitivity of the individual. Scratching a bite may break the skin, resulting in secondary infections.

Ants: 

In so far as they affect us at all, most ants are little more than nuisances in kitchen or garden. However, the imported fire ants of the South bite viciously and in dangerously large numbers when a colony is disturbed. Individual workers can sting repeatedly, and companies may attack at once. The stings produce an intense burning sensation, later blistering and forming a white pustule.

Fire ants generally live in large, heavily crusted earthen mounds that may be eighteen inches high and contain over 100,000 workers. Unfortunately, they can also take up residence in house walls or under cracked pavement.

Although some imported fire ants are black, the most common are reddish-brown. As with other ants, males and most workers live no more than a few weeks, but queens can live up to seven years. Only males and females (during the mating period) have wings.

Larvae develop in six to ten days, then "pupate", to emerge two weeks later as adults. Since there may be more than one queen per colony and mature queens can lay 800 eggs a day, numbers can expand rapidly. New colonies can "hive off" from the mother colony and appear to be established in no more than a few days.

Ticks: 

Travellers walking through dense undergrowth or exploring caves may find ticks or mites attached to their skin but they are relatively easy to remove with a pair of tweezers: grip the tick firmly under the head end and push down to disengage the "teeth" then gently pull away. Once the tick has been removed, treat the bite area with antiseptic.

Ticks are responsible for spreading diseases such as typhus,   encephalitis and lyme disease.

Scabies is caused by a small mite which burrows into the outer layers of the skin and cause the characteristic itch which can be almost unbearable but the mite does not carry any infectious disease. In order to catch scabies it is necessary to be in close contact with an infected person for some time. The itch develops six to eight weeks after infection. Treatment consists of applying an insecticidal lotion containing benzyl benzoate, malathion or carbaryl.

One species of mite endemic to South East Asia can cause Relapsing Fever which is a form of typhus.

Note: Ticks and mites are actually arachnids and not insects.