Green Bottle Fly: All You Need To Know About Green Bottle Fly

The green bottle fly, weird name, right? these green colored flys are a very helpful species to human beings as they among others are capable of laying maggots on wounds which help to heal the wounds. But don’t trust them so quickly for as it is said everything with an advantage has a disadvantage, so it is with these guys.

They can also be pests as they lay eggs on the naked parts of the body such as the eyes, nose, ears, etc. and can become a drastic problem if these eggs which later develop to maggots get to the brain as it may result to death.

Freaky right? indeed most of us are very well familiar with some pests such as the ants, spiders, bees, house centipede and lots more but never before have you heard of this particular pest. Well, lucky for you we’ve got you covered join us on this info-filled research-based journey as we’ve scanned through the world of the green bottle fly and brought it to exposure. Fasten your seatbelts and enjoy the ride!



Green Bottle Fly Facts

The green bottle fly sometimes referred to as the blowfly or screwworm is found in most areas of the world and is the most well-known of the numerous green bottle fly species. Its body is about 10 to14 mm i.e 0.39 to 0.55 in length and is slightly larger than a housefly. One difference between the housefly and the green bottle fly is that the housefly is any fly regularly found in human dwellings while the screwworm is any of various flies of the family Calliphoridae that lay their eggs in rotting meat, dung, or in open wounds.

They have brilliant, metallic, blue-green or golden coloration with black markings. It has short, sparse bristles (short stiff hair) and three cross-grooves on the thorax. Its wings have light brown veins, and the legs and antennae are black. The larvae of the fly may be used for maggot therapy, are used in forensic entomology, and can be the cause of myiasis in livestock and pets.

Green Bottle Fly
Green Bottle Fly

Green Bottle Fly
Green Bottle Fly Feeding on Pollen

Green Bottle Fly Behavior

  • Feeding

Once the eggs of the green bottle fly are laid directly into the decaying flesh of dead animals, they are able to hatch and feed on the corpse until they migrate to the pupa stage. They are very beneficial to mankind through their feeding habits as they feed on both pollen and feces, therefore serving as important agents of pollination and decomposition. Pollen serves as a very good source of protein especially to pregnant females who can’t always find decaying flesh. These flies are capable of digesting the pollen, perhaps with the assistance of bacteria in their digestive tracts. Notably, these pregnant flies are particularly attracted to flowers that produce dead decay-like odor, such as the S. tuberosa and S. javanica. These flowers trick the flies into pollinating them by mimicking the scent of dead decaying flesh. However, the flies also frequently visit myophilous flowers such as the Leucanthemum vulgare and are attracted to the color yellow as well as to the scent of flowers. This proof analyzes the fact that the flies are attracted to flowers not only because they smell like dead decaying flesh (in the case of the S. tuberosa and S. javanica), but precisely for the pollen offered by the flower (in the case of the Leucanthemum vulgare).


See Also: Honey Bees


  • Mating

The process of mating in the green bottle fly is a very complex system and most of the roles are played by the male. The male first identifies a potential mate and pushes her with his head; he then taps her with his foreleg several times. The male then mounts the female and attempts mating, continuously tapping his foreleg on her body.

If the female is willing to mate the copulation proceeds, genital contact is achieved, and when the process is over both fly part ways. If she is not willing, the female will kick at the male with her hind legs, but this has no effect at all in dismounting the male and the mating proceeds nevertheless. Some males are left-biased and some males are right-biased in their foreleg tapping, but this bias has no effect on the mating process.

Green Bottle Fly
Green Bottle Fly Mating


  • Care for Offsprings

The females lay their eggs on fresh dead decaying flesh, avoiding older decayed flesh because of the bacterial activity or other factors. Female screwworms perform mass laying of eggs, laying their egg masses in carcasses that other female flies are also laying in. The presence of female flies eating or ovipositing on a carcass urges other female flies to do the same, perhaps through chemical cues.

Females exhibit a preference for certain oviposition (laying of eggs) conditions; they attempt to maximize the survival potential of their offspring by laying eggs in only the best places. They often prefer to lay eggs on wet fur, and not on wounds, as is mistakenly thought by many. Pregnant female green bottle flies prefer warm temperatures for their offspring since this will decrease development time and therefore increase the survival potential of the offsprings, this also is because they oviposit faster and with more eggs in warmer decaying flesh.

Green Bottle Fly Life cycle

The Life cycle of the green bottle fly is from the adult→ egg→ larva→ pupa stage. Females can lay 2000-3000 eggs in 9-10 batches within three weeks. Wow! Temperature is one of the many great factors that affect and determine the number of eggs a female oviposits. Eggs are usually laid on crevices (openings) of moist decaying organisms. Screwworms like to lay their eggs areas that are usually exposed to light.

Maggots hatch from the eggs and attach themselves to the dead decaying flesh they have been installed into. After about 4-9 days the maggots are done with development and then go into the pre-pupa stage where they will bury themselves into the soil and then pupate into a pupa. In this stage, the maggot is encompassed in a hardened shell where it will cast off its old cuticle and grow wings. They are motionless, incapable of eating, and cannot protect themselves. The pupa stage will last about 7 days depending on soil temperature.
Adult flies will then escape from their pupa and journey above the surface of the soil just like the tarantula wasp hawk.  The fly is soft at first and does not contain its bright green color. It takes the body of the fly 2 days to harden, the color display begins and fully functional wings emerge. Mating occurs and the cycle rotates all over again!

Green Bottle Fly
Green Bottle Fly Maggot


Green Bottle Fly Maggots

Maggots hatch from the eggs and attach themselves to the dead decaying flesh they have been installed into. After about 4-9 days the maggots are done with development and then go into the pre-pupa stage where they will bury themselves into the soil and then pupate into a pupa.

It has been studied that the green bottle fly maggots are known to consume dead tissue but still leave the tissue intact, so they have been suggested for use in maggot therapy (A study involving the installment of life, disinfected maggots into the non-healing skin and wound of a human or animal for the purpose of cleaning out the dead tissue within a wound and for the purpose of disinfection).  The developmental stage of their larvae (maggot) in a corpse can be used for accurate determination of the time of death.

Green Bottle Fly Benefits

They serve as useful agents of pollination just like the bees.

They assist in the decomposition of dead decaying matter.

The maggots help in the treatment of non-healing wounds.

They are used in forensic entomology to determine the time of death of a victim.


Green Bottle Fly Infestation

One of the common reasons for flies swarming all over your house is an infestation inside or nearby your home. When you notice a swarm of flies flying around your home that means eggs have already hatched and developed into flies. The source is obviously within your house, garage, attic or garden and should be exterminated.

Obviously the adult flies will depart in late summer to lay their eggs in the soil. The cluster fly larvae are parasitic on earthworms and will pupate in the soil, emerging as adults ready to find shelter for the winter. But you wouldn’t wait that long, would you? Assuming you decide to wait for that period of time till they return to the soil, these flies will develop into adults and still visit you during the winter period as they cluster together for warmth in wall voids and in your attic, to ride out the long cold winter. They are strongly attracted to light, so they are usually found around windows and at night around lamps.


How to Get Rid of Green Bottle Fly

Yes, of course not everyone will want these pests in their homes as they may grow to become a nuisance so certain steps have to be taken to send them parking. Below are ways of getting rid of the green bottle fly;

  • By use of Chemicals

Step 1 Spray insecticide on the walls of your home.

Step 2 Use broom or vacuum to dust away dead flies.

Step 3 Still use insecticide again in the infested area.

  • By use of Vinegar

Step 1 Put some vinegar in a bowl.

Step 2 Mix with detergent to reduce the surface tension of the mixture.

Step 3 The mixture attracts the flies and they drown due to low surface tension.

  • Spray cinnamon air fresheners as these pesky pests hate its fragrance
  • Use of venus fly trap


We’ve come to an end of a very interesting and epic journey. Surely this article has been of so much help to certain questions that have evolved in our minds concerning this pest. For further clarification contact us

About The Author

Discover more from Pestclue

Subscribe to get the latest posts to your email.

Leave a feedback

This site uses Akismet to reduce spam. Learn how your comment data is processed.