Flies


The most common observed stage of a fly is the winged adult. The adult fly mates, lays eggs in a breeding medium that will provide sufficient food for the immature stage – a pale, legless maggot. The breeding site is nearly always moist and surrounds the soft-bodied maggots. When maggots are full grown, they stop feeding and usually wander from the breeding site in search of a place to pupate. After pupation, they emerge as an adult fly. In warm weather, flies complete their development (egg-larva-pupa-adult) in an incredibly short period, 7-14 days, and produce numerous generations during a typical season.




House Fly


BIOLOGY / CHARACTERISTICS

Each female fly can lay approximately 500 eggs in several batches of about 75 to 150. The eggs are white and are about 1.2 mm in length. Within a day, larvae (maggots) hatch from the eggs; they live and feed in (usually dead and decaying) organic material, such as garbage or feces. They are pale white, 3-9 mm long, thinner at the mouth end, and have no legs. At the end of their third instar, the maggots crawl to a dry cool place and transform into pupae, colored reddish or brown and about 8 mm long. The adult flies then emerge from the pupae. The adults live from two weeks to a month. After having emerged from the pupae, the flies cease to grow; small flies are not young flies, but are indeed the result of getting insufficient food during the larval stage.

Houseflies can take in only liquid foods. They spit out saliva on solid foods to predigest it, and then suck it back in. They also regurgitate partly digested matter and pass it again to the abdomen.

These flies can walk on vertical planes, and can even hang upside-down from ceilings. This is accomplished with the surface tension of liquids secreted by glands near their feet.


Blow/Bottle Fly


BIOLOGY / CHARACTERISTICS

Blowflies are about the same size as the housefly, and look very similar. They are usually metallic blue or green, and therefore they are also called bluebottle or greenbottle flies.

The eggs are laid on the material that serves as food for the larvae, e.g., decaying flesh and other organic matter. Blowflies are often carriers of disease, such as dysentery. The larvae of certain species of blowfly, raised under germ-free conditions and known as surgical, or medicinal, maggots, are used to consume dead and dying tissue and thus promote healing.