Blow Flies

Facts, Identification & Control

Latin Name

Family Calliphoridae

Appearance

What Do They Look Like?

blow fly picture

  • Color: Adult blow flies are often metallic, while larvae are pale in color.
  • Characteristics: Adults have sponge-like mouth parts, with feathery hairs on the terminal antennal segments of the males. Larvae have hook-like mouth parts.
  • Larvae: Blow fly larvae are also known as maggots. Measuring 9 to 22 mm in length, maggots are equipped with hook-like mouthparts and spiracles for breathing. They are soft and appear similar to worms or grains of rice. Each body segment of the blow fly maggot has a median row of fleshy tubercles that resemble hair.

How Did I Get Blow Flies?

These pests get into homes through open doors, windows, or small cracks in walls in search of food. Once inside, blow flies find a meal and begin to deposit eggs on its surface.

How Serious Are Blow Flies?

Disease Transmission
These flies transfer infections to humans through contaminating food and food preparation surfaces. Also it is possible to transfer disease organism when a blow fly comes into contact with an open wound or lesion on people, livestock or pets. When the insects feed, pathogens attach to their bodies. These pests can spread dysentery, eye infections, and other illnesses.

Related Problems
A blow fly infestation often indicates a more serious issue. These pests gather in large numbers around carrion. An indoor swarm is a sign of an animal carcass trapped in an attic or wall void.

Signs of Infestation

Adults can be spotted resting on surfaces or checking out potential food or odor sources. Spotting larvae often happens when they move out of breeding sources to pupate.

How Do I Get Rid of Blow Flies?

Your local Orkin technician is trained to help manage blow flies and similar pests. Since every building or home is different, your Orkin technician will design a unique program for your situation.

Orkin can provide the right solution to keep blow flies in their place…out of your home, or business.


Behavior, Diet & Habits

Blow flies belong to the Family Calliphoridae of flies under the Order Diptera. To date, there are approximately 80 species in North America.

What Do They Eat?
Blow flies are attracted to decaying meat and are typically the first organisms to come into contact with dead animals. The meat of dead animals is essential for larval survival and growth. They are also attracted to plants that give off the smell of rotting meat and as such, can be a pollinator for those plants.

Where Do They Live?
Blow fly maggots are generally seen near dead animals. Different species of blow flies are active at different times: the Calliphora vomitoria are most commonly found on carrion during cooler months, while the Phaenicia sericata are more active in hot seasons. Other species thrive more in the shade, while some require hot temperatures to complete the maggot developmental stage.

Life Cycle

life cycle chart

Larvae or Maggots
Female blow flies typically lay their eggs on decaying meat, where maggots hatch within a few hours to a few days depending on species. These maggots undergo three stages within several days, after which they leave their food source and pupate in soil. Within a few  days, the pupation will be complete, at which point they emerge as adults.

Blow fly eggs are laid in rotting meat, where maggots feed and complete their development before seeking a dry location within which to pupate. After maturing, larvae create outer skins, known as puparia, that look like rat droppings or cockroach egg cases. Pupae develop within the puparium, maturing into adults.