The BSF, a tropical and temperate dipteran insect, is adapted to large-scale production considering its short life cycle, the great size of its immature stage, the high number of eggs, and bioconversion efficiency. Females lay between 320 and 620 eggs. Four days later, the larvae hatch and go through six larval instars, including the prepupae, then pupate. The larvae are beige and possess photoreceptors that allow them to flee the light. They can eat a wide variety of organic matter such as manure, fruits and vegetables, food waste, and fish offal and can reduce up to 50% of their feeding substrate dryly. They also have a high conversion efficiency since they can produce 1 kg of larvae biomass with 1.4 kg of ingested feed compared to cricket and mealworms, which require 2.3 and 3.8 kg, respectively. The BSF larvae reach the prepupal stage in 10 to 52 days and weigh 300 mg depending on the feed offered and the rearing temperature. It then stops eating and initiates melanization, resulting in a darker coloration of the cuticle a few hours before molting becomes a prepupa. During this stage of 7 to 10 d, the prepupa migrates to a dry place to metamorphose into a pup. The pupal stage, during which larvae do not move nor eat for at least eight days, ends with the adult emergence. Because the imago does not eat, it uses its accumulated reserves to meet its metabolic needs. The fly mates and lays its eggs in 8 to 9 living days. The most nutritious stages are the larval ones (larva and prepupa) and are, therefore, the most often harvested by BSF producers.
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