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Tick
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Tick is the common name for the small arachnids in superfamily Ixodoidea that, along with other mites, constitute the Acarina. Ticks are ectoparasites (external parasites), living by hematophagy on the blood of mammals, birds, and occasionally reptiles and amphibians. Ticks are important vectors of a number of diseases, including Lyme disease and Tick-borne meningoencephalitis.
Young ticks have six legs, and mature ticks have eight legs. They are about the size of a sesame seed, and males are black; females have a brick-red abdomen with a black shield-like plate close to their head.
s are blood-feeding parasites that are often found in tall grass and shrubs where they will wait to attach to a passing host.
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Tick is the common name for the small arachnids in superfamily Ixodoidea that, along with other mites, constitute the Acarina. Ticks are ectoparasites (external parasites), living by hematophagy on the blood of mammals, birds, and occasionally reptiles and amphibians. Ticks are important vectors of a number of diseases, including Lyme disease and Tick-borne meningoencephalitis.
Young ticks have six legs, and mature ticks have eight legs. They are about the size of a sesame seed, and males are black; females have a brick-red abdomen with a black shield-like plate close to their head.
Habitats and behaviors
Ticks are blood-feeding parasites that are often found in tall grass and shrubs where they will wait to attach to a passing host. Physical contact is the only method of transportation for ticks. Ticks do not jump or fly, although they may drop from their perch and fall onto a host. Some species actively stalk the host by foot.
Changes in temperature and day length are some of the factors signaling a tick to seek a host. Ticks can detect heat emitted or carbon dioxide respired from a nearby host. They will generally drop off the animal when full, but this may take several days. In some cases, ticks will live for some time on the blood of an animal.
Ticks can be found in most wooded or forested areas throughout the world. They are especially common in areas where there are deer trails or horse paths.
Some of the more common diseases that can be contracted from a tick bite include: Babesiosis, Ehrlichiosis, Lyme disease, Rocky Mountain spotted fever, Southern tick-associated rash illness, Tick-borne relapsing fever, and Tularemia.
Population control
Case study of the American Deer Tick
The blacklegged or deer tick (Ixodes scapularis) is dependent on the white-tailed deer for successful reproduction. Larval and nymph stages (immature ticks that cannot reproduce) of the deer tick feed on birds and small mammals. The adult female tick needs a large 3 day blood meal from the deer before she can reproduce and lay her 2000 or more eggs. Deer are the primary host for the adult deer tick and are key to the reproductive success of the tick. See the Connecticut Agricultural Experiment Station and Connecticut Department of Public Health joint publication "Tick Management Handbook" for more details of the tick's life cycle and dependence on deer.
Numerous studies have shown that abundance and distribution of deer ticks are correlated with deer densities.
For example, when the deer population was reduced by 74% at a study site in Bridgeport, Connecticut, the number of nymphal ticks collected at the site decreased by 92%. Furthermore, the relationship between deer abundance, tick abundance, and human cases of Lyme disease was well documented in the Mumford Cove Community in Groton, Connecticut, from 1996 to 2004. The deer population in Mumford Cove was reduced from about 77 deer per square mile to about 10 deer per square mile (4 deer per square kilometer) after 2 years of controlled hunting. After the initial reduction, the deer population was maintained at low levels. Reducing deer densities to 10 deer per square mile (4 deer per square kilometer) was adequate to reduce by more than 90% the risk of humans contracting Lyme disease in Mumford Cove. Deer population management must serve as the main tool in any long-term strategy to reduce human incidences of Lyme disease.
Other control measures
Also, the Centers for Disease Control and Prevention offers advice on reducing ticks around your home.
The parasitic Ichneumon wasp Ixodiphagus hookeri has long been investigated for its potential to control tick populations. It lays its eggs into ticks; the hatching wasps kill its host.
Another "natural" form of control for ticks is the Guineafowl. They consume mass quantities of ticks. Just 2 birds can clear in a single year.
Topical (drops/dust) flea/tick medicines need to be used with care. Phenothrin (85.7%) in combination with Methopren was a popular topical flea/tick therapy for felines. Phenothrin kills adult fleas and ticks. Methoprene is an insect growth regulator that interrupts the insect's life cycle by killing the eggs. However, the EPA has made at least one manufacturer of these products withdraw some products and include strong cautionary statements on others, warning of adverse reactions.
To control ticks outdoors so they don’t get transmitted inside, you can use liquid spray using a hand sprayer or a hand spreader. Using the amount instructed on the label for liquid spray and granule. Apply the solution and granule uniformly on the entire lawn, large turfs, and other landscaped areas. Apply on bushes, wooded and shaded areas as well. If there is already a tick infestation inside the home, you can use liquid spray using a hand sprayer with a mist and pinpoint nozzle, dust using a duster and aerosol. This is very important because once a tick infested with Lyme disease is in your home. Using the amount instructed on the label, apply the liquid solution and aerosol around window/door frames, window sills, cracks and crevices, near pet areas, baseboards, corners, storage areas, closets, around utility pipes, attics and eaves, cabinets, sinks, furnaces, stoves, behind and under refrigerators, and carpets. Pay special attention to pet areas. Ticks may be on the bed and furniture, it is safe to be used on beds and furniture. After the application of liquid solution and aerosol, leave the house for about 3 hours and ventilate the house once you come back only if you sprayed the whole entire carpet, or mattress. After you come back home, steam vacuum the home thoroughly. Reapplications may be needed. If that is the case, reapply to retreat the home.
Example species
*Dermacentor variabilis, the American dog tick, is perhaps the most well-known of the North American hard ticks. This tick does not carry Lyme disease, but can carry Rocky Mountain spotted fever.
- Ixodes scapularis (formerly Ixodes dammini), known as the black-legged tick or deer tick, is common to the eastern part of North America and is known for spreading Lyme disease.
- Ixodes pacificus, the Western black-legged tick, lives in the western part of North America and is responsible for spreading Lyme disease and Rocky Mountain spotted fever. It tends to prefer livestock such as cows as its adult host.
*Australia tick fauna consists of approximately 75 species, the majority of which fall into the Ixodidae, hard tick, family. The most medically important tick is the Paralysis tick, Ixodes holocyclus. It is found in a 20-kilometre band that follows the eastern coastline of Australia. As this is where much of the human population resides in New South Wales, encounters with these parasites are relatively common. Although most cases of tick bite are uneventful, some can result in life threatening illnesses including paralysis, tick typhus and severe allergic reactions.
- The southern cattle tick, Boophilus microplus (Canestrini), causes annual economic losses in the hundreds of millions of dollars to cattle producers throughout the world, and ranks as the most economically important tick from a global perspective. This tick also attacks sheep, horses, goats and a few related species, but cattle are the most important hosts.
- The Lone Star tick, Amblyomma americanum, is part of the Ioxdidae family, classifying it as a hard tick. The adult females are distinguished by a white dot or "lone star" on its back. The adult males can also be seen with dots and white streaks on the edge of their bodies. This tick has been associated with transmission of Southern Tick Associated Rash Illness (STARI) in humans, which is a disease caused by a Borrelia sp. related to the agent that causes Lyme Disease.
See also
Fossil record
Fossil ticks are rare but not unknown. The oldest example is an argasid (bird) tick from Cretaceous New Jersey amber. The younger Baltic and Dominican ambers have also yielded examples; all of which can be placed in living genera.
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