Pham Van Be has been running his black soldier fly farm for five years in Duc Hoa District, Long An Province, which borders Saigon to the west. After working as a teacher for more than two decades, he shifted to farming pigeons and snakes before settling on the black soldier flies.
The black soldier fly, Hermetia illucens, is a species widely cultivated in many countries. Their larvae are nutrient-rich food for pigs, poultry and seafood. The insect is also used to treat waste in agriculture and craft villages.
"From my previous experience in pigeon rearing, I learnt that birds which feed on larvae grow faster. I looked up more information to find that black solider flies are not harmful to the environment and they grow well, so I reared some as an experiment. It was difficult at first because this species is quite hard to find in nature," said 50-year-old entrepreneur.
The farm covers an area of 500 square meters that houses 32 enclosures or cages. Be invested more than VND100 million ($4,308) on building the farm. Its ceilings are installed with many fans to facilitate ventilation and balance the temperature with the external environment.
The cages are basically mosquito nets, covering 10 to 30 square meters each. They are always closed to prevent the flies from leaving. Each cage hosts about 100,000 flies.
This species lives for a month, growing from eggs to larvae and then pupae and eventually into flies," said Be. "At this stage, they don’t eat anything and only live for seven days, lay eggs and then decay."
Inside the cages, there are thin wooden bars tied together with elastic bands with cracks in the middle for the flies to lay eggs in. "This breed usually lays eggs in cracks so doing this emulates their natural habitat. Each cage has a bucket of food for them to stimulate reproduction."
Each black soldier fly lays 500-700 eggs. Workers use a knife to gently prise them out and collect them in a tray.
"When we take eggs, we have to be very gentle to avoid breaking them," said Phat, an employee. "Every other day, the farm will collect about two kilograms of eggs and sell them for VND20 million ($861) per kilo."
Another area of the farm is dedicated to incubation where the flies go through their life cycle, from an egg into a fly in 20 days.
The food for the black fly larvae is mainly rotten vegetables. "We collect this from markets. This species are voracious eaters throughout their whole life. A kilogram of larvae consumes two to three kilos of fruit," said Be.
Black fly larvae are used as feed for poultry, cattle, seafood, and so on, and their cocoons as fertilizer.
Each month Be’s farm generates about two tons of pupae, but it only sells a small amount to the market, retaining the rest for breeding. The farm mainly sells eggs to livestock, poultry and aquaculture farms so that they can produce black fly soliders themselves.
Be said that after deducting expenses, he earns more than VND100 million ($4,308) each month.