Know your enemy: The Fly

Summertime is beach time, bach time, barbecue time and fly time. As the temperatures creep up, the invaders buzz in – especially in the early evening when cooking smells waft invitingly from open doors and windows. As the saying goes, it’s good to know your enemy – so we’ve done some digging about flies. 

What are flies?

Flies come from a large and highly successful biological order that has about 150,000 species worldwide (even Antarctica!). They have a single pair of transparent wings and sucking or piercing mouthparts. The members of this family that you’ll know the best are houseflies, blowflies, mosquitoes, midges, gnats and fruit flies.

What’s the problem with flies?

Food sources for flies include plant sap, blood, dead things, decaying organic matter and whatever you’re eating. Because flies can only suck liquids, they vomit on solid food sources so that digestive juices, enzymes and saliva can liquefy the food.

If flies eat food from a bacteria-laden source, such as a rubbish bin or excrement, bacteria stick to the fly’s legs and mouthparts. When the fly lands on its next meal (your dinner?), these bacteria transfer. Flies are highly mobile, so the interchange between bacteria sources and human food happens quickly.

How can you control flies?

» Physical controls: As well as ensuring that organic rubbish is stored in a closed bin outside the house, you can use air curtains and insect screens to keep flies out. An efficient rangehood can prevent cooking smells from moving through the house. It’s also good to avoid piles of grass clippings, doggy dos and any other kind of animal manure. If you make your own compost, try to keep it dry and turn the mix every two to three days – wet compost heaps full of food scraps are a feeding and breeding ground for flies. 
» Surface sprays: Ecomist has a highly effective surface spray called Insect Sniper . It can be sprayed onto areas that are frequented by flies (look for fly specks) – warm sunny places that are close to attractive odours. Be careful in kitchen areas; avoid getting surface spray onto utensils and surfaces used for preparing food.

» Space sprays: Natural Pyrethrins, such as those used in Ecomist Insect Killer , give very rapid knockdown and are safe to use around humans. When flies encounter small droplets of pyrethrins, they head for the light and go into a bit of a dance as their nervous systems is affected. Shortly thereafter, they die. As well as killing flies that venture into their range, Ecomist Automatic Insect Control Dispensers  ensure there’s enough pyrethin in the air to repel flies that are thinking about coming inside.

Information sources: Urban Pest Management in Australia 5th Edition (2008). Gerozisis, J; Hadlington, P; Staunton, I.
Utah Education Network www.uen.org