Common Housefly (Musca domestica) adults are 6 – 8mm in length with a wing span of 13 – 15mm. They have large compound eyes, mouth sucking parts and segmented feet on the end of each leg.
The lesser housefly is 6mm long with a 12mm wingspan and three longitudinal stripes which are less pronounced than those of the common housefly.
A typical female can lay around 9,000 eggs, which are white and 1.2m in length. She usually lays them on dead or decaying organic material (e.g. faeces, corpses) so that once hatched they are able to feed. They hatch within 1 day as white maggots.
After 3 days of feeding, the maggot moves away to find somewhere warm and dry to pupate (transform), which is usually in soil. After 4 days they have transformed into a pupa and 10 days later, they eerge as a fly.
Household flies can carry intestinal worms and diseases, such as gastroenteritis, dysentery, typhoid, tuberculosis and cholera.
Houseflies feed by regurgitating digestive juices and their stomach contents onto food. The acid liquefies the food which they suck up using specialized mouth parts. They often pick up pathogenic organisms which survive their gut or stick to their bodies, which are passed on when they land on their next snack. Fly spotting is produced when the fly feeds or defecates.
Pest Control Methods
Flies are highly mobile and multiply quickly. To be effective, pest control methods have to target both the larvae and adult population simultaneously.
The larvae can be targeted by limiting breeding sites in the local area. E.g. Storing rubbish in sealed containers or refuse sacks.
Insecticidal sprays, dusts, lacquers and strips can be highly effective.
UV light traps can be installed near food or other problem areas. Fly traps with bait may be useful for localised fly problems.