Mosquito
From BWCAWiki
Mosquitoes are flying, biting insects in the family Culicidae. They have a pair of scaled wings, a pair of halteres, a slender body, and long legs. The females of most mosquito species suck blood from other animals. While the BWCAW, and Minnesota in general, has a reputation for large populations of aggressive mosquitoes, actual conditions vary considerably with geography, season, and recent weather.
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Life cycle
The mosquito undergoes complete metamorphosis, going through four distinct stages in its life cycle: egg, larva, pupa, and adult. The length of the first three stages is dependent on the species and temperature. Culex tarsalis may complete its life cycle in 14 days at 20 °C (68 °F) and only ten days at 25 °C (77 °F). Some species have a life cycle of as little as four days or up to one month. The larvae are the "wrigglers" or "wigglers" found in puddles or water-filled containers. These breathe air through a siphon at the tail end. The pupae are nearly as active as the larvae, but breathe through thoracic "horns" attached to the thoracic spiracles. Most larvae feed on microorganisms, but a few are predatory on other mosquito larvae.
After metamorphosis, male and femal adult mosquitoes behave differently. In most females, the mouth parts form a long proboscis for piercing the skin of mammals (or in some cases birds or even reptiles and amphibians) to suck their blood. As opposed to a syringe's typically smooth needle, the mosquito proboscis is highly serrated, which leaves a minimal number of points of contact with the skin being pierced — this reduces nerve stimulation to the point where the "bite" is not felt at all, which is generally the case. The females require protein for egg development, and since the normal mosquito diet consists of nectar and fruit juice, which has no protein, most must drink blood to get the necessary protein. Males differ from females, with mouth parts not suitable for blood sucking.
Most mosquito species outside of the tropics overwinter as eggs, but a significant minority overwinter as larvae or adults.
Variability of abundance
Due to the requirement of standing stagnant water for the larval stage of their life cycle, mosquitoes are found in greater numbers around suitable habitat, such as wetlands and small ponds. The suitability of this habitat increases with a period of wet, warm weather; likewise an extended dry spell will decrease the amount of available larval habitat and therefore decrease adult populations.
Mosquitoes seem to be most active at dawn and dusk, sometimes for as little as 45 minutes. Mosquitoes dislike strong direct sunlight, preferring shade and twilight.
Adult mosquitoes cannot tolerate freezing temperatures, although their eggs are not affected.
Attraction
Although scientists continue to study what attracts mosquitoes to humans, it has been found that mosquitoes generally find their prey by sight, smell, and heat. Carbon dioxide, released when humans exhale, may be a mosquito attractant, as well as the increased temperature and humidity of the breath. Various scents and compounds given off by the skin including sweat, lactic acid, heat, moisture, and foot odor all may be attractants. Mosquitoes seem to be attracted to dark colors (black, blue, red) more than light colors (tan, white, yellow). Alcohol consumption may increase mosquito attraction. [1] [2] [3]
Deterrence
Seasonal avoidance
Spring and fall frosts kill adult mosquitoes, making for a "bug-free", albeit cooler, experience. Several weeks of dry weather will decrease the mosquito populations, even in mid-summer.
Campsite selection
Due to their tiny size, adult mosquitoes have difficulty flying in more than a 10-15 mph wind. When choosing a campsite, lightly forested sites on islands and points may get more of a breeze than other locations, making mosquito conditions more tolerable.
Also, choosing campsites surrounded by steeper, rockier terrain rather than low, swampy land may have some affect, although results vary.
Behavior
Try to stay cool and avoid strenuous activity if possible.
Clothing
Long sleeved shirts and long pants are the easiest physical deterrent to mosquitos. Broad brimmed hats and bandanas covering the neck are also useful.
In extreme cases, a "bug net" may be desired to protect the head. Most consist of fine nylon mesh which extends down from the brim of a hat, covering the head and neck.
Chemical repellants
Many visitors to the BWCAW swear by chemical repellants such as DEET or citronela. While effective, these sprays or oils are generally strong smelling. Most experts believe DEET is safe when used as directed, although there is some concern about DEET's toxicity and absorption through the skin when applied directly. [4] [5] Young children are more sensitive to DEET than adults. Users of DEET should be careful not to handle certain plastics and rubber, as DEET is a chemical solvent and will dissolve some materials.
Chemical repellants made from natural plant oils are becoming increasingly available, although their effectiveness may not yet match that of DEET.
References
Parts of this article are originally from WikipediA, The Free Encyclopedia.
