The Black Soldier Fly Challenge
I believe black soldier fly larvae represent the most logical method for dealing with the constant stream of putrescent waste that humans create. Putrescent waste is anything that gets putrid (rots) and is mostly wasted food. Like all skeptics I immediately started looking for the negative aspects of processing this waste with BSF, and while they aren’t magic it’s hard to imagine a much more efficient solution to a growing problem.
Bio-conversion
The process of feeding organic wastes to black soldier fly larvae is called bio-conversion. That’s because the process doesn’t exactly eliminate the garbage, it converts it into BSF larvae. Rotting garbage is a liability and BSF larvae are a valuable asset. You can read more about bio-conversion HERE.
Generally accepted data about black soldier flies and larvae
- They are not associated with the transmission of diseases
- They don’t bite or sting and they avoid human habitats
- Their presence in waste deters or even eliminates house fly reproduction in that waste
- Larvae rapidly consume almost any organic waste except for high cellulose items like yard waste
- Larvae reduce the volume of household food waste by up to 95%
- A 2 foot (60cm) container of larvae can process 5 lbs. (2.3kg) or more of household food waste in 24 hours
- When larvae mature they will self harvest using a simple ramp system
- Live larvae are very nutritious and are readily consumed by many different animals (pigs, chickens, reptiles, fish, etc)
- Meal made from dried larvae is roughly equal to Menhaden fish meal, a valuable and widely used ingredient in animal feeds.
The challenge
I’m making the claim that bio-conversion of putrescent waste with BSF larvae is the best way to deal with the constant stream of rotting waste that goes into landfill. The challenge is simple, state any significant problem that might be caused by using BSF to convert our organic garbage into nutritious animal feed or high quality products for industry such as bio-fuels.
Let’s not wait
Burying our food waste in giant rotting mounds is ridiculous given the elegant solution represented by bio-conversion with black soldier fly larvae. The technology already exits and represents the essence of sustainablity. What in the world are we waiting for?
The only question I have about using the self-harvesting BSF composters is about the effect this harvesting has on the wild BSF population levels. I’m interested in BSF larvae as chicken feed. I compost with red wiggler worms and much prefer the idea of self-harvesting feed. Does giving the wild BSF females a place to lay their eggs, catching the mature larvae, and then using them as feed reduce the levels of helpful BSF in the ecosystem? I don’t see how it couldn’t since the females are choosing to lay eggs in the composters which will ultimately feed their larvae to my chickens instead of them laying their eggs in a dung pile somewhere to make more helpful flies for the next generation.
Any thoughts on this would be helpful. I don’t want to feed generations of helpful insects to my hens to the detriment of my farm’s ecosystem.
Hi Jesse,
I do not believe that maintaining a BSF colony in this fashion will have a detrimental impact on your wild population. In fact, since the systems I blog about here rely on reproduction by free ranging adults it’s in your best interest to increase the wild population. These systems contain the larvae, but the adults remain wild.
I’ve been told that the male/female ratio for BSF is roughly 1 to 1. Estimates for egg production from a single female are 500-900, or an average of 700. If each pair of BSF adults produces 700 offspring then to maintain a stable population (no increase in size) 698 of the 700 eggs produced must not survive to reproduce. Only two adult BSF need to survive and reproduce for each 700 larvae to maintain the population. I have always promoted the practice of allowing a small percentage of larvae to pupate and emerge as adults. I usually suggest that while people are initially building up their colony that they minimize the amount of larvae that are used as feed. Once the colony is the proper size for your goals I recommend allowing 5 or 10% of the larvae to survive to adulthood. The actual numbers will vary for each situation, but with experience you’ll get a feel for what size colony is necessary to support the amount of feed you wish to produce. As the estimates above indicate; in nature the survival rate to adulthood is much less than 5-10%.
My brain isn’t functioning very well this morning so if you still have questions please feel free to ask.
Hi,
I am looking into BSF for a larger scale production on our ranch, for feeding a couple hundered chickens and about 10 pigs. I was wondering if there is any research ,you know about, for this larger scale? Is it possible, how would I go about starting an operation like this? Any info you can give me would be great.
Thanks
Hi I agree with everything Jerry says except for the ratio of males to females. From a couple studies I looked at, it appears in one study that males out number females 2 to 1. In another study they divided them into Male:female:sexless. I have also seen a study that said females were 11% larger than males on average. What that means to me is that there are more males/sexless than females. I chop up the larvae for my fish and so I usually pick out the larger ones to spare assuming these are the one that are likely female. I also gather a random hand full to spare as well… I would hate the females not to have any suiters
. The only thing I don’t know is if a male can mate more times than one. I have not seen anything on this.
My operation is small scale. I only harvest between 100 and 300 larvae a day right now. Most of my input is fruit scraps from a fruit stand. My system gets a lot of water, but it seems to work.
[...] soldier fly larvae are welcome residents of compost piles designed for bioconversion, the process of turning decomposing matter into [...]
the digestor and the breeding are two different aspects
the digestor does not work without insects, insects need organic matter to develop and live.
one should have both elements to close the cycle
Our compost got invaded (no better word) with black soldier fly larvae. Our initial reaction was, “what the heck are these?” They seemed to be eating the garbage so we let them be. There’ll be millions (approximate number) of them around next year from our compost. I hope they lay in our compost again; maybe I’ll try fishing with them. Thanks for the article.
charles where are you located?