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Blow and Flesh Flies
Need to know
- Blow flies and flesh flies are very common flies associated with dead animals.
- Blow flies and flesh flies lay their eggs in recently deceased animals. The larvae infest the animal carcass for 5-10 days before they leave the carcass and wander in search of a dry place to pupate.
- Both the maggots and flies are harmless.
- Control adult flies by swatting or using a ready-to-use indoor insecticide labeled for fly control.
Descriptions of blow and flesh flies
Blow flies and flesh flies are very common flies associated with dead animals. The larvae (maggots) of these flies feed on dead animal tissue and as such are beneficial in nature as decomposers of dead animal carcasses. The appearance of these flies or maggots in the house typically indicates that an animal (i.e. rodent, bird, etc.) has died within the walls or in the attic.
Life cycle of blow and flesh flies
Blow flies and flesh flies are attracted to recently deceased animals, where they lay their eggs. The larvae infest the animal carcass for 5-10 days before they leave the carcass and wander in search of a dry place to pupate. These maggots are unsavory but harmless.
Maggots that are left to develop turn into adult flies in 5-7 days. These are large, sluggish, black or shiny green or blue flies. These flies are harmless. The flies will not deposit eggs or further develop inside the house. By the time the flies emerge, the original carcass is too old and dry for reinfestation.
Management of blow and flesh flies
The only necessary control for flesh fly maggots is to vacuum or sweep them up and discard them. Then check for dead animals in the walls, attic, etc. Control adult flies by swatting or using a ready-to-use indoor insecticide labeled for fly control.
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