The Black Soldier Fly

Image  credit: wikimedia commons

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All life fits into an ecosystem somewhere. Even what some may consider an annoying creature has a role to play in our intricate and interconnected world. One of those “annoying” creatures is the fly. However, the black soldier fly (Hermetia illucens) doesn’t have the typical characteristics of the annoying housefly that interrupts your lunch and quiet while you sleep. In fact, they are beneficial in ways beyond the niche they fill in our ecological community.

Image Credit: Wikimedia Commons

So, this fly is a bit different in appearance to the common housefly. The adults measure about 5/8 inch long. They have a predominantly black body with metallic blue to green on the thorax and a reddish-brown abdomen. They have a wide head and very developed eyes. Their habits are different as well. They don’t buzz around and land on your doughnut releasing digestive juices and bacteria like the housefly. Instead, they are much calmer, can be caught easily, and the spreading of pathogens isn’t a problem. They prefer hiding if they are able. Their metabolic rate isn’t as high, so they fly around less.

The life cycle of a black soldier fly begins as an egg.  The eggs incubate for about 3 days. The entire life cycle can take anywhere from 44-73 days. The time for each stage is dependent upon temperatures and food access. Warmer temperatures are best for the quickest stage development. During the larval stage they may go through 6 instars or stages of shedding and growth. This process takes about 14 days. Then they pupate for 1-2 weeks before emerging as a fully formed black soldier fly. Then they mate, lay eggs and the whole process begins again.

The larvae eat almost constantly, breaking up particles with their mouth parts. Eating in masses together they stir up their food and heat it up with the energy they give off thus increasing the rate of compost. They love compost, household organic waste and manure. They can quickly reduce a compost pile by 50% if the weather is warm. As adults they move less and mostly drink liquids. Their main goal is mating and laying eggs.

In nature the black soldier fly can usually be found around livestock and farms due to their desire for compost and manure. This attribute can be utilized in and around homesteads, small city chicken coops, compost piles and farms.

Image  credit: wikimedia commons

 The larvae have many uses. These include feed for poultry, fish, pigs, lizards, turtles and are sometimes incorporated into dog food. They have a nice balance of healthy fats, nutrients, and amino acids. So, for this reason could they be used for human food? Absolutely. It is reported that when cooked they smell like cooked potatoes, have a crispier outside and a soft yummy inside with a nutty meaty taste. Yum!!! In 2013 Austrian designer, Katharina Unger, produced a tabletop insect breeding farm called Farm 432 ( that can produce a bit over a pound of larvae a week. The larvae are not only a nutritious protein filled meal for us but is also used to produce chitin, a polymer derived from glucose, to aid in removing biofouling (organic buildup) from pipes and the hulls of ships. The larvae manure is called frass and has its own use as organic fertilizer. Nothing goes wasted in nature.

Image credit: pixabay

You could even set up a self-feeding or collection station for your pigs, chickens, and ducks. In an existing contained compost bin, you could construct a ridged tube from the bottom of the bin that leads to a bucket outside. The larvae have a natural tendency to climb. Use that aspect and give them a tube to crawl up and simply set a bucket at the end for them to drop into. Or just let the chickens and ducks wait at the end for a snack.

credit: pixabay

In conclusion, we have examined the lifecycle, and many uses of the larvae for Hermetia illucens. Get innovative and construct your own chicken food producing station.  You can do it with minimal engineering knowledge and just a visit to the hardware store. Explore a sustainable source of protein to create culinary delights such as larvae burgers and crunchy bits for salads and stews.  As you snack you can revel in the knowledge that this less buzzy fly has not only a niche in nature, but a place in our world as we move closer to sustainability.

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Shana M Ritch

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