Data related to
A BLACK FLY (sometimes called a BLANDFORD FLY, BUFFALO GNAT , TURKEY
GNAT, or WHITE SOCKS) is any member of the family SIMULIIDAE of the
Culicomorpha infraorder . They are related to the
* 1 Ecology * 2 Regional effects of black fly populations
* 3 Public health
* 3.1 River blindness
* 4 See also * 5 Notes * 6 References * 7 External links * 8 Bibliography
Eggs are laid in running water, and the larvae attach themselves to rocks. Breeding success is highly sensitive to water pollution. The larvae use tiny hooks at the ends of their abdomens to hold on to the substrate, using silk holdfasts and threads to move or hold their place. They have foldable fans surrounding their mouths. The fans expand when feeding, catching passing debris (small organic particles, algae, and bacteria). The larva scrapes the fan's catch into its mouth every few seconds. Black flies depend on lotic habitats to bring food to them. They will pupate under water and then emerge in a bubble of air as flying adults. They are often preyed upon by trout during emergence. The larva of some South African species are known to be phoretic on mayfly nymphs. A female black fly
Adult males feed on nectar, while females exhibit anautogeny and feed
on blood before laying eggs. Some species in
Different species prefer different host sources for their blood meals, which is sometimes reflected in the common name for the species. They feed in the daytime, preferably when wind speeds are low.
Black flies may be either univoltine or multivoltine , depending on the species. The number of generations a particular pest species has each year tends to correlate with the intensity of human efforts to control those pests.
Work conducted at
Portsmouth University in 1986–1987 indicates
REGIONAL EFFECTS OF BLACK FLY POPULATIONS
Black flies attack a canoe expedition in July 2015 in the
Canadian Arctic, Dubawnt River ,
* In the wetter parts of the northern latitudes of
Only four genera in the Simuliidae family,
Mature adults can disperse tens or hundreds of kilometers from their
breeding grounds in fresh flowing water, under their own power and
assisted by prevailing winds, complicating control efforts. Swarming
behavior can make outdoor activities unpleasant or intolerable, and
can affect livestock production. During the 18th century, the
"Golubatz fly" (
Bites are shallow and accomplished by first stretching the skin using teeth on the labrum and then abrading it with the maxillae and mandibles , cutting the skin and rupturing its fine capillaries. Feeding is facilitated by a powerful anticoagulant in the flies' saliva , which also partially numbs the site of the bite, reducing the host's awareness of being bitten and thereby extending the flies' feeding time. Biting flies feed during daylight hours only and tend to zero in on areas of thinner skin, such as the nape of the neck or ears and ankles.
Itching and localized swelling and inflammation sometimes result from a bite. Swelling can be quite pronounced depending on the species and the individual's immune response, and irritation may persist for weeks. Intense feeding can cause "black fly fever", with headache, nausea, fever, swollen lymph nodes, and aching joints; these symptoms are probably a reaction to a compound from the flies' salivary glands . Less common severe allergic reactions may require hospitalization.
Repellents provide some protection against biting flies. Products containing the active ingredient DEET (N,N-diethyl-meta-toluamide) or picaridin are most effective. However, given the limited effectiveness of repellents, protecting oneself against biting flies requires taking additional measures, such as avoiding areas inhabited by the flies, avoiding peak biting times, and wearing heavy-duty, light-colored clothing, including long-sleeve shirts, long pants and hats. When black flies, for example, are numerous and unavoidable, netting that covers the head, like the “bee bonnets” used by beekeepers, can provide protection.
Black flies are central to the transmission of the parasitic nematode Onchocerca volvulus which causes onchocerciasis , or "river blindness". It serves as the larval host for the nematode and acts as the vector by which the disease is spread. The parasite lives on human skin and is transmitted to the black fly during feeding.
* ^ Daley, Beth (2008-06-23). "Black flies surge in Maine\'s clean
rivers". Boston Globe. Retrieved 2008-06-23.
* ^ The Canadian Encyclopedia: Black