The humble house fly—that pesky plague carrying pest that’s been around since the dinosaurs—is prolific during the summer months. Milder weather spawns the hatching of house fly eggs, releasing new populations of hungry flys who ruin picnics and barbecues relentlessly with their annoying buzzing around people and food.
Hark back to Year seven science class and you may remember your teacher telling you about house fly feeding activity. For example:
Fly lands on faeces (animal or human—it’s not fussy which) and because it can’t chew it spits out dissolving enzymes, mushes the saliva into the faeces with its feet, sucks up the “soup” through its sponging, straw like mouth, regurgitates it and repeats the procedure until it is sated. Later, when it’s hungry again, it will do the whole thing over, perhaps on your picnic or that freshly baked cake you left cooling on the kitchen counter. (flies have quite a sweet tooth – or sponge, in their case).
Flies vomiting on food is the sort of information that remains etched in the mind of delicate students for the rest of their life, and plays a huge part in why humans hate flies. Flies, on the other hand, love humans.
Flies are attracted into homes, schools and workplaces by heat and smells. Flies are also drawn to rotting animal carcasses, but are equally happy with the just-out-of-the-oven roast your were allowing to sit uncovered before carving it up for Sunday lunch.
This nasty nuisance not only has horrible feeding techniques, it is also the transporter of disease-carrying organisms, such as those causing diarrhoea. These are picked up when the fly crawls around disease infested matter such as poop. Organisms that stick to the legs and body of the fly can survive for a few hours, being transmitted to surfaces the fly lands on. Germs and bacteria ingested by the fly may remain in its gut for several days, and are regurgitated each time the fly feeds on your food—remember that science lesson!
Controlling and discouraging flies
- Clean work and household surfaces regularly and thoroughly.
- Clean up spills quickly.
- Keep rubbish contained and remove it often.
- Flies are attracted by smells – keep the toilet fresh and the bin covered.
- Cover non-refrigerated foods.
- Keep pet feeding and litter areas clean.
- Flies breed in rotting organic matter – cover compost heaps.
- Clean drains of sewage sludge.
Fly sprays and chemical control should be used as a last resort since flies can become resistant to these making them more difficult to control. Try these other methods instead:
- Plant aromatic herbs such as basil, mint and lavender, place them near near windows and outer doors. Crush the leaves and sprinkle them along windowsills, or as a potpourri on your kitchen worktops or desk.The aroma of these herbs repel flies.
- Light aromatic candles or oil burners at your picnic or barbecue to deter all sorts of pests, including flies.
- Set fly traps – a simple jar with some cider vinegar and a paper funnel will draw flies in (by the scent) but they will be unable to get out.
- Hang fly papers and change them regularly (no one likes to see multiple fly corpses hanging from the ceiling).