Circles Big and Small

The circular economy is defined as a model of production and consumption that involves sharing, leasing, reusing, repairing, refurbishing and recycling existing materials and products as long as possible. In this way, the life cycle of products is extended. Recycling wastes is an essential practice under this approach.

Black soldier flies, with their impressive ability to extract nutrients from a wide variety of organic wastes and convert them to a usable biomass, could be a great fit in many, if not most, circular economies. An obvious example will be black soldier flies reared on an aquaculture sludge, harvested, processed into aquafeed, and then fed to fish. This way, nutrients circulate in the system instead of being hauled away and buried in a landfill. This is the cycle that most people think about when talking about using black soldier flies "to close the loop" between production and waste management.

There are, however, other ways how black soldier flies can contribute to building circular economies. These cycles may be smaller in terms of the amounts of materials involved, but they are still important. For example, amending soils with black soldier fly frass helps kale grow. In turn, feeding black soldier fly larvae with kale waste will enrich them with lutein, thus increasing the value of animal feeds made from such larvae. Moreover, chitosan derived from black soldier fly skins can increase bioavailability and stability of ingested lutein.

As more information on black soldier flies becomes known every day, the number of ways they can contribute to building sustainable economies is certain to grow. Right now, we are just beginning to unlock potential of this amazing species.