Mating
The female mates about 36 hours after emerging from the pupa. She must feed after copulating for egg development. Egg laying (oviposition) begins four to 20 days after mating.
Eggs
The female will lay six to eight groups of eggs, with each group containing 75 to 150 eggs. The eggs hatch into first stage (instar) larvae between 8 and 20 hours after being laid.
Larvae
A legless larva (maggot) emerges from the egg and immediately begins feeding. There are three larval instars with molting of the larval skin after the first and second instar stages. Larvae complete development in four to 30 days.
Pupae
The third larval instar skin dries to form the pupal case. The fly pupates for about five days before emerging as an adult.
Adults
The adult life span is generally 15 to 25 days and, sometimes, up to two months. The life cycle generally takes seven to 12 days and can be long as two months.