Journal of the Department of Agriculture, Western Australia, Series 4 Volume 8 Number 12 1967 Article 5 1-1-1967 The house fly Clee Francis Howard Jenkins Follow this and additional works at: https://researchlibrary.agric.wa.gov.au/journal_agriculture4 Part of the Entomology Commons, and the Environmental Microbiology and Microbial Ecology Commons Recommended Citation Jenkins, Clee Francis Howard (1967) "The house fly," Journal of the Department of Agriculture, Western Australia, Series 4: Vol. 8 : No. 12 , Article 5. Available at: https://researchlibrary.agric.wa.gov.au/journal_agriculture4/vol8/iss12/5 This article is brought to you for free and open access by Research Library. It has been accepted for inclusion in Journal of the Department of Agriculture, Western Australia, Series 4 by an authorized administrator of Research Library. For more information, please contact [email protected]. INSECT PESTS THE HOUSE FLY (Musca domestic ) By C. F. H. JENKINS, M.A., Government Entomologist MANY insects are so commonly associated with man and his dwellings that they may almost be called domesticated. In olden days the presence of these insects was accepted as a matter of course, but present knowledge shows that many of them can be important disease carriers while others may cause damage to food and clothing. There is no more widely known pest or LIFE HTISTORY disease carrier than the house fly. Volumes A single fly may lay from five to twenty have been written dealing with its habits batches of eggs, each batch containing and control, but it still remains one of from 75 to 150 eggs. The elongated light- the most important problems of the medi­ coloured eggs measure about l-25th of an cal entomologist. The name "common inch in length and take from eight to 24 house fly" is quite an appropriate one, for hours to hatch under optimum conditions. the insect is cosmopolitan. The small white maggot grows rapidly and There are several local flies which closely passes through a number of instars or resemble the house fly and are often con­ stages, each stage being marked by a fused with it. The two commonest are the moulting or shedding of the skin and an bush fly (Musca vetustissima), and the increase in size. stable fly (Stornoxys calcitrans). Both are small greyish flies about the size of the house fly, but they seldom come indoors. The species which pesters one when on a country walk and clusters thickly on one's back is not, as popularly believed, the house fly, but the bush fly. The stable fly may be quickly recognised by its stiff piercing mouth parts and its "bite" for again contrary to the popular idea, the house fly never "bites." Description of adult fly The adult house fly measures about a quarter of an inch in length and has transparent wings. The body is greyish and the thorax is characteristically marked with four dark longitudinal stripes. These stripes distinguish the house fly from the '/ bush fly, for in the latter each pair of dark tripes converges towards the base to form The house fly (enlarged) a Y-shaped mark. (After Gibson and Twinn) 503 Journal of Agriculture, Vol 8 No 12 1967 When fully grown the maggot passes RELATION TO DISEASE through an inactive pre-pupal stage, dur­ The house fly exemplifies one of the ing which no feeding is done and after simplest types of disease transmission by which it buries itself in the soil to pupate. insects, the role of the fly being merely The larval stage may cover from three that of a mechanical carrier. As already to five days in favourable weather and stated, flies infest and breed in all manner the pupation time an equal period. From of refuse such as garbage, damp lawn the figures quoted it will be evident that clipping, human excreta, and various types the house fly can complete its life cycle of manure. Under such circumstances in a little over a week. A further period they have every opportunity of coming of from seven to fourteen days normally in contact with disease-contaminated elapses however before a female can lay material, tiny portions of which may eggs, so that the interval between succes­ either be swallowed or carried about sive generations is about three weeks. adhering to the hairs of the legs and body. HOW LONG DO HOUSE FLIES LIVE? Bearing in mind the house flies' liking It must be clearly understood that the for sugar, milk and other foodstuffs, it is time taken to complete any particular not difficult to understand how easily even stage may be greatly protracted by cold or a single fly can contaminate food and other adverse weather conditions. The drink by merely settling on them. larval stage, for instance, may extend The habit of regurgitating a drop of fluid over a month or more under certain cir­ in order to moisten certain foods offers an cumstances, consequently an adult fly can additional means of contamination since emerge in a week or several months from viable bacteria are known to have occurred the time of egg laying, according to in "fly specks." In order to emphasise the whether conditions are favourable or potentialities of the house fly as a disease otherwise. Furthermore, the adult fly itself carrier, may be quoted the fact that a may live for a period of weeks or months single insect has been known to carry well according to conditions. If these particu­ over 6,000,000 bacteria. lars are kept in mind the old question, Amongst the diseases carried by the "Where do the flies go in the winter house fly are typhoid, cholera, various time?" offers little difficulty. Much of the population dies out if conditions are par­ types of dysentery and ophthalmia and ticularly adverse but a portion survives in tuberculosis. No further propaganda than various stages of development and is able the above list should be required for an to bring about a rapid build up of numbers anti-fly campaign, and yet only too often when the opportunity arises. the matter is given but scant attention. HOW FAR DO THEY FLY? Control Normally house flies do not range very SANITATION far afield although under certain circum­ The first essential for fly control is strict stances they may travel several miles sanitation. This applies not only to the down-wind. One investigation in America involving the release of 54,000 marked immediate vicinity of dwellings, stables house flies showed that 1,216 were re- and dairies but to the disposal of garbage, caught within half of a mile of the release lawn clippings, fowl manure and other centre, 272 between one and four miles organic matter which only too often is distant, and only four at a distance of piled in some out of the way corner or eight miles. This and other experiments, shovelled into a shallow pit. If garbage coupled with general observations, indicate is buried it should be treated with an that when flies are numerous, the breed­ insecticide if already fly struck and covered ing source is usually close at hand. with at least a foot of compacted soil. WHERE DO THEY BREED? GARBAGE TINS House flies will breed in almost any type of decaying organic material, but they are Garbage tins should have close fitting particularly attracted to all types of lids and all materials should be wrapped animal manures, compost heaps, lawn before disposal. Moist waste should not be clippings and kitchen garbage. placed in garbage cans. Mi Journal of Agriculture, Vol 8 No 12 1967 COMPOST can only be obtained if the necessary It is not generally realised that lawn attention is also given to general hygiene clippings and various other garden refuse and the disposal of garbage, manure and can breed house flies if left in a neglected other fly breeding media. On no account heap. Where composting is not carried out should baits and sprays be used as alter­ grass cuttings should be spread out thinly natives to the more fundamental methods over the garden where they will dry quickly of control, as the indiscriminate use of and cause no fly hazard. If a compost pit chemicals may finally lead to the develop­ is used then the clippings should be put ment of insecticide resistant flies, and so, immediately into the pit and covered wtih to the intensification rather than the relief a layer of soil to keep off flies. of the fly problem. Where fowls are kept, the droppings Space Sprays (for indoor use) should be cleaned up daily before fly in­ festation has occured and either spread (i) Pyrethum -f synergist = rapid out thinly to dry, or placed in a compost knockdown. No residual action. pit with a thin covering of soil. (Concrete (ii) Pyrethum + synergist and residual sided pits or boxes with fly proof covers additive (e.g., DDT, Methoxychlor, lin­ are satisfactory for composting, but they dane) = rapid knockdown plus some should be actually fly proof and not just residual action. a roughly covered container to which flies have easy access. Baits (i) Impregnated mats and crystal baits STABLE MANURE (containing Dipterex, Diazinon, DJD.V.P.*, Manure should be collected and disposed etc.), may be used inside or outside—near of daily by thin spreading. Where this is resting sites. not possible, fly breeding may be reduced (ii) Bait sprays (Dipterex, Diazinon, by tightly packing the material on a con­ Malathion, etc). These materials are gen­ crete base with a 6 in. ditch containing erally used at 0.1 per cent, concentration water surrounding the heap.