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Temperature and humidity were approximately the same for both batches of larvae. The large larvae is one of the three that was separated for the photos and all three are similar in size. The small larvae is from the more crowded container which held the bulk of the larvae. The same type of food was available to both groups, but I can’t attest to the quality of the food in the more crowded environment that produced the smaller larvae. From casual observation it appeared that there was always food available to both groups. The most obvious difference between the two containers was the density of larvae. The small larvae where moved into a larger container six days after hatching and seem to be healthy and growing, but are still relatively small.

I imagine any properly educated researcher would not be surprised by this difference in development, but to this layman it’s very interesting.

There are more than 100,000 species of flies, but in most people’s minds a fly is a fly, period. The species most people automatically think of are the house flies, blow flies, and bottle flies. Our disdain for these pests is understandable because they are known transmitters of human diseases, but non-pest black soldier flies are different in several ways. The most important difference is that BSF are not vectors of human pathogens. Black soldier flies rarely go into human habitats or land on people, and the adult black soldier fly doesn’t even eat during it’s short lifespan. Now that I’ve gotten that out of the way, on to the mythbusting.

Swarms of black soldier flies = myth

I’m convinced that most people imagine a swarm of black soldier flies hovering around a BSF composting unit such as a BioPod. They would be wrong. I’ve been culturing black soldier fly larvae for one and a half years and the greatest number of winged adults I’ve seen at any one time is less than 10. Most of the time when I check my BioPod there are no flies near it. I don’t think I’ve ever seen one before noon (apparently they sleep in), and you don’t see them when the sun is low or at night.

In case I haven’t made my point, BSF adults (winged stage) are relatively rare. One reason is that the adults only live a few days, just long enough to breed and lay eggs, and then they die. Contrast this with house flies that live 30 days or more. In the short period that BSF spend as adult flies there just isn’t enough time for big social gatherings such as swarms.

Black soldier flies pester people = myth

Black soldier flies can’t bite or sting and they don’t eat so they have no interest in people. As mentioned above you probably won’t see many BSF adults and if you do they will usually ignore you. On the rare occasions when a BSF adult lands on me it’s most often when I’ve been handling larvae and I have their scent on my hands. They land then because the subtle scent of BSF larvae is a powerful attractant to BSF females and if one lands on me I always pause to admire this beautiful beneficial insect. To be honest, I usually refer to any BSF adults I see around the BioPod as “the girls”, because males are not attracted to the unit. All of the BSF near the BioPod will be females looking for a good site to lay eggs.

To be continued… larvae, biopod, composting, black soldier fly, flies, composter

Update 8/25: Since I’m aware that anyone can modify a Wikipedia entry I went there to investigate the process. I assumed there would be a detailed system of presenting information and waiting for a consensus before changes would be allowed. Nothing of the sort. Registration was simpler than with most internet forums and it was automatic and instant. I registered and then began looking for the form where I could make my recommendations for editing the black soldier fly entry. There is no such thing, but there is an edit button. I clicked “edit”, changed a few things and then saved it. That’s all there was to it. A 10 year old could do it. Wikipedia can be a valuable source of information, but it relies on consensus and this can lead to problems with obscure subjects such as black soldier flies. I will continue to edit this Wikipedia entry until it accurately depicts black soldier flies.

I considered deleting this post about Wikipedia since the issue will soon be resolved, however it can still serve to illustrate the problems with relying on Wikipedia as a reference source.

ORIGINAL POST:

First, it’s important to understand how Wikipedia functions.

This is from the Wikipedia entry about itself:

Wikipedia (pronunciation ) is a free,^[5] multilingual, open content encyclopedia project operated by the United States-based non-profit Wikimedia Foundation. Its name is a portmanteau of the words wiki (a technology for creating collaborative websites) and encyclopedia. Launched in 2001 by Jimmy Wales and Larry Sanger,^[6] it attempts to collect and summarize all human knowledge in every major language.^[7]

Critics of Wikipedia target its systemic bias and inconsistencies^[12] and its policy of favoring consensus over credentials in its editorial process.^[13] Wikipedia’s reliability and accuracy are also an issue.^[14] Other criticisms are centered on its susceptibility to vandalism and the addition of spurious or unverified information.^[15]

SOURCE

Wikipedia is an open content “encyclopedia”, and here is their definition of open content:

Open content, a neologism coined by analogy with “open source“, describes any kind of creative work published in a format that explicitly allows copying and modifying of its information by anyone, not exclusively by a closed organization, firm or individual. The largest open content project is Wikipedia.^[1]

In other words you, or I, or anyone else can modify any Wikipedia entry.

How does Wikipedia get black soldier flies wrong?

The problem with the Wikipedia entry for BSF at this time is that it’s very unbalanced and poorly referenced. You can click the image below to see a view of the entry as it was on 8/21/08.

(click to enlarge)

Of the six bullet points about BSF I believe that one is incorrect and another is misleading:

The larvae can be destructive pests in honeybee hives

I have heard this before, probably from people who have read this Wikipedia entry, but I have found no research to back it up. All I could find was a reference to BSF larvae inhabiting abandoned hives found in the walls of houses. I can’t imagine how a BSF adult or larvae could survive in an active beehive. BSF are truly defenseless creatures that lack stingers and the adult flies don’t even have functional mouth parts.

I tried finding documentation of this claim from the three sources the article sites as references. The first study didn’t mention bees and in fact the title of the study refers to BSF as “a Non-Pest Native Fly”. The second source deals with forensic science and refers to black soldier fly larvae collected from a couple of  bear carcasses. The third source is a print article and I couldn’t locate a copy of the July 2007 issue of Reptiles magazine.

If anyone finds evidence that BSF can be “destructive pests in honeybee hives” please present it to me because I don’t believe it.

The larvae may sometimes cause intestinal myiasis or pseudomyiasis in humans. See this case in Costa Rica[1]

Whoever wrote this did use the word “may”, but an entry like this is unbalanced if it doesn’t describe how rare this potential event actually is in the case of BSF. The point of an encyclopedia is to present information in such a way that the reader gains a basic overall understanding about the subject. Due to the sensational quality of myiasis this statement it is likely to be overemphasized by the average reader. Anyone who clicks on the word myiasis in this Wikipedia sentence will be taken to a page that describes this very disturbing condition where a fly larvae inhabits the inside of person. This is sensational, but not balanced reporting in the case of BSF.

It’s possible that a BSF larvae will survive in a human gastrointestinal tract if it’s swallowed whole which is why I always recommend chewing them well. I found references to a few cases worldwide involving BSF over the last 50 years, and in those few cases no serious or lasting damage was attributed to BSF larvae.

The fact is that this possible occurrence is exceedingly rare and would most likely be caused by people eating from garbage cans. A BSF female seeks out rotting food on which to lay her eggs, not fresh. Furthermore, there is research that suggests that BSF larvae actually control pathogens in waste such as salmonella and E coli. That means a person who ate from garbage inhabited by BSF larvae might be spared a severe illness or even death.

How does Wikipedia describe rattlesnakes?

This is the entire overview section from the rattlesnake entry at Wikipedia:

There are approximately fifty species of rattlesnake, with numerous subspecies. They receive their name for the rattle located at the tip of their tails. The rattle is used as a warning device when threatened. The scientific name Crotalus derives from the Greek, κρόταλον, meaning “castanet“. The name Sistrurus is the Latinized form of the Greek word for “tail rattler” (Σείστρουρος, Seistrouros) and shares its root with the ancient Egyptian musical instrument, the sistrum, a type of rattle.

Most rattlesnakes mate in the spring. All species give live birth, rather than laying eggs. The young are self-sufficient from birth. As they do not need their mother after birth, the mother does not remain with her young.

No mention of venom or human deaths? If you didn’t already know that rattlesnakes are dangerous you might think they use their rattles to calm little babies. Yes, we all know that rattlesnakes are dangerous, but this still represents unbalanced reporting by Wikipedia. You have to read halfway down the lengthy entry  to the “Safety and identification” section to find a reference to rattlesnakes biting humans. You would think that the the safety section would mention the fact that these beautiful animals can be deadly to humans, but you would be wrong.

Wikipedia entry for Rattlesnake

And finally, the black soldier fly photo from Wikipedia:

I’ve seen a lot of images of black soldier flies and the one at Wikipedia is the only one I would call sinister looking. I’ll bet the vast majority of people who see that image immediately assume that the BSF is stinging the tree. Could these “soldiers” be so aggressive that they sting trees for no reason!? In fact that is a female black soldier fly laying hers eggs. Unlike disease carrying flies, BSF prefer to lay their eggs above and away from the food source and not on it. BSF mimic wasps in appearance as a defense because in reality they are totally vulnerable creatures.

To put Wikipedia’s accuracy into even greater doubt place your cursor over the original image on the Wikipedia page. You will see the file name for this photo which is “Wasp 1454″. If you don’t know the difference between a wasp and a fly you shouldn’t be creating encyclopedia entries.

Doesn’t everyone know to take Wikipedia entries with a grain of salt?

Well hopefully anyone who reads this post will!

Black soldier flies are common in tropical and subtropical regions, but their range extends to the most northern states of the continental U.S. You can easily operate a BSF bio-composting unit in northern states during the warm months, but you can also maintain the colony through the colder months with a little extra effort.

A black soldier fly colony generates its own heat

Maintaining a BSF unit in cold weather is possible because the metabolic action of the larvae eating creates heat as a byproduct. Under cold conditions keeping the colony at the optimal temperature range of 85° - 100°F (30°-38°C) is as simple as consistently feeding them and placing an insulating material directly on top of the pile. Simply remove the insulating material, add the food scraps, and then replace it. It’s important to feed the colony consistently in cold weather because without food the temperature will drop and the colony will become dormant. If the larvae are exposed to freezing temperatures they will die. Also, any insulation on top of the colony needs to have an air gap between it and the BioPod.

Maintaining a BSF colony during extended periods of sub-freezing weather is possible, but it may be more than you wish to get involved with. In that case you can enjoy BSF culturing up to the point where the weather in your area makes it difficult and then resume in the spring.

Process more food scraps, harvest less larvae

In cold weather the time it takes BSF larvae to mature increases from the usual few weeks to a period of up to several months. The colony has little or no crawl-off of mature larvae and that enables you to continue bio-composting without the need to replenish the larvae via visiting females.

In warm weather the colony has a tendency to overheat, so in cool weather the larvae are able to consume even more food scraps.

How adventurous are you?

I don’t recommend bringing the BSF unit into your living room, but why not try keeping it in the garage or a shed when the temperature drops? Sure, a few larvae might get out, but so what? The adult fly will just emerge from it’s pupae in the spring and then you’ll have the pleasure of gently capturing it and releasing it outdoors. They are harmless creatures after all. I don’t think a heated space would be the best choice though, because it might trick the larvae into developing too quickly. I would guess that 40° - 60°F (5°-15°C) is a good range to try testing this theory, and of course you would need an insulating disc of some sort to keep the colony warm. The degree of insulation would depend on the ambient temperature in the space.

I’m cursed with living in an area that rarely gets cold so if you try this experiment please let me know how it goes. I would love to post photos of your set up (if it works ).

The purpose of this post is to feature a blog that is valuable to anyone researching black soldier flies. It’s called BioSystems Design Weblog and below is an excerpt from their “about” page.

About BioSystems Design

BioSystems Design LLC. is dedicated to the transformation of what was previously considered waste into valuable products.  Our institutional knowledge and designs are based on nature, as nature is the premier designer of BioSystems that use waste as production inputs.

Our studies of nature and Biosystems are conducted in Bogotá, Colombia, at our two research laboratories, with our prestigious partner organizations, La Universidad Nacional de Colombia and Universidad de La Salle.

BioSystems Design LLC.  maintains close partnerships with ESR International and Otterwasser Gmbh.   Our commitment to ESR International is the design, construction, and operation of an industrial production process that feeds crop and food waste to larvae, harvests that larvae, cooks it, pulverizes it, and sells the high protein larvae-meal to animal feed producers.

Our commitment to the German wastewater consultancy, Otterwasser Gmbh, is to sell, build, and operate their innovative energy generation and wastewater treatment systems in the United States.

BSF post from their blog:

Black Soldier Fly: Compiled Research On Best Cultivation Practices

The following represents the “nuts and bolts” facts relevant to Black Soldier Fly cultivation which were found buried inside of research texts. The key distinguishing factor is that they are organized by environmental considerations (in bold). Where inconsistencies are found they are noted. Assistance, suggestions, along the lines of additional sources, inconsistencies, and added environmental considerations are highly welcome. I hope to make this a very active post.

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 or paper.
• Larvae reduce the volume of household food waste by up to 95%.
• A 2 foot (60cm) container of larvae can process several pounds 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 possible method for processing putrescent waste. The challenge is simple, state any significant problem that might be caused by using BSF to convert our organic garbage into nutritious animal feed.

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?blog, biopod, composter,

The coffee colored BSF larvae (prepupae) are the final stage before pupation into adult BSF. To our advantage they are programmed by nature to crawl away from the food source in search of a suitable pupation site. In a properly designed BSF unit these larvae crawl up a ramp and drop into a collection bucket where they will live for weeks without any maintenance.

The method described below is for harvesting the earlier stages when the larvae are actively feeding and growing. It doesn’t work for the mature larvae because they don’t eat therefore aren’t attracted to the bait in the collection container. It works very well for the light colored immature larvae.

The Immature Larvae Collection Device or ILCD (old butter tub)

Take a cheap container and cut some small holes around the bottom edge.

(click on images to enlarge)

Add something delicious (any food scraps will do), and simply place it on the surface of the compost. I used fish food because I’m training my fish to eat it and this is a good way to introduce them to the flavor (I feed the larvae to the fish). Just about anything will work, but drier items might make handling the collected larvae easier.

The photo below was taken 2 minutes after placing the tub on top of the compost.

This is after 11 minutes.

The photo below was taken 40 minutes after adding the container.

This quick harvest totaled about 2 cups (.5 litre) of small to medium larvae. I don’t have many large larvae at this time due to the crash I caused in the colony a few weeks back. I do have a lot of larvae, just not large ones yet.

fishing, bait,

I’ve been feeding BSF larvae to my redear sunfish (shellcrackers) everyday for about a week and they are taking them with enthusiasm. They have a preference for the immature larvae over the dark prepupal larvae, but they still eat the dark ones pretty well. I think the prepupal larvae might be more foreign to them than the light colored larvae, but I think with some conditioning they will eventually accept  them just as well. There are some individual fish that already take the prepupae well which is why I suspect it isn’t a taste issue or something like that.

(Wow. That video quality is terrible. I’m open to suggestions if anyone would like to offer some advice about uploading video. I’ll leave this up for now, but I have to do something! I tried blip.tv and PhotoBucket which were better quality, but the embedded players for these sites ruined the xhtml validation for my blog, the YouTube videos don’t.)

Here’s a link to a better quality version of the same video at Blip.tv - VIDEO

Update - August 14

These fish are in a pond that was built in January 2008 and I only stocked 24 adult redears. (I also stocked 110 very small redears in late March and you can see a few of them feeding with the larger fish in the video) At first when I began feeding them BSF larvae the fish were concentrated in one area of the pond because they were on spawning beds. This made it very convenient to hand feed them, but I assumed they would disperse once the spawning season passed. Well, the spawning seems to be over and they’re still concentrated in the same spot, and I’m pretty sure it has something to do with the daily offerings of black soldier fly larvae. Lately when I walk up to the feeding area I see the fish lining up just off the bank of the pond about one meter from the water’s edge. All fish are oriented on me as they wait for the rain of tender BSF morsels. They will swim into water that is only a few inches deep to snatch up the larvae. Previously I was unaware of the popularity of fly larvae as fish bait, but now I can understand why they are so effective.

If you’re a sensative person you may hesitate at the idea of sacrificing the larvae to fish this way but there is another way to look at it. In nature fly larvae have a high mortality rate and the balance of the population is based on the vast majority of them not surviving to reproduce. Two BSF can produce between 500 and 900 eggs depending on which report you read, and to maintain the normal population only 2 of those several hundred will survive to lay more eggs. I address this issue in more detail here: Feeding black soldier fly larvae to other animals

After working with and blogging about black soldier fly larvae for over a year I finally have one of the first BioPods. For the past year I’ve been getting by with my homemade unit and I’m looking forward to testing this product. With that previous experience I’m pretty familiar with the shortcomings of my unit and from what I can tell by looking, the BioPod addresses those problems.

I’m starting this colony from scratch

I already have a colony of BSF larvae established, but I want to take this opportunity to start a BioPod from scratch. On one hand it seems like I’ll have an advantage starting this new colony because I have an established BSF population on my property, but that may not be an advantage. My existing colony which is 200 feet (60 meters) from my new BioPod is a powerful attraction to any female BSF looking to lay their eggs. BSF larvae do not have a strong or unpleasant odor, but their scent is easily picked up by the adult females.

The bait

The BioPod user’s guide recommends starting your colony with normal household food scraps except for meat or fish. It’s not a problem to feed meats or fish to an established colony, but before that stage those items will attract too many unwanted critters. I started my first colony using assorted scraps, but for this unit I’m using only dry dog food. I added 2 cups (.5 liters) of it, slightly moistened. The humidity where I live is usually 50% or higher so I don’t think I’ll need to wet it further. The purpose of wetting it in the first place is to enhance the smell and it may not even be necessary. The reason I’m testing with the dog food is because some types of food scraps start to look nasty after a few weeks and the dog food is fairly stable. In the end it probably doesn’t make much difference, but it’s hard for me to follow instructions sometimes.

JULY 10

This is the day my BioPod arrived. I set it up in about 20 minutes, added the bait, and so far that’s all I’ve done. It’s important to deter ants from entering the BioPod so I’m going to treat the legs of the stand with a small amount of Bug Stop.

JULY 15

It’s been raining a lot lately and that seems to slow down the BSF adults. I haven’t observed any BSF or seen any eggs on the new BioPod yet. This morning when I checked it there were a few house flies on the lid and I could smell the dog food from outside. Inside there were a few fruit flies and nothing else.

JULY 20

Still no sign of black soldier flies in the BioPod, even though they’re active only a few hundred feet away.  I guess this reinforces the idea that if you maintain a BSF colony that you won’t have them all over your property. I’ve seen a few house flies on the BioPod lid but none inside. This may be because they aren’t willing to enter the small opening in the BioPod. My homemade unit had a fair amount of house flies entering it at this stage.

The dog food I used as an attractant is beginning to mold and I don’t think it was necessary to moisten it. Still not bad for 10 days in the summer though.

It can be frustrating waiting for the BSF to show up at your BioPod. I think the key is getting that first female  to lay her eggs in your BioPod. Once that happens I think the others will quickly follow.

JULY 24

Still no luck in the new BioPod and I may have a clue why it’s taking this long, even with the healthy BSF population on my property.

I’m sure this one frog isn’t the only reason it’s taking a while and it may be the other colony I have on the property is getting all of the attention. Still, that is one well fed frog.

JULY 27

Okay, first of all, the frog was back! The frog from the photo has some unique markings and I believe the one I saw today was the same frog. The first time I moved it about 50 feet, this time I tried 100.

Other than that I want to say UEREKA! I now have BSF eggs in my new BioPod. I’m surprised how long it took, but as I mentioned earlier I believe my other colony was attracting most of the females.

It won’t be long now!

(egg disc removed from BioPod for photo)

AUGUST 1

I have a few different types of larvae feeding in the BioPod now which are too large to have come from the eggs in the photo above. I think I’ve seen one of these species in the past when starting a BSF colony, and I think it may be one of the other soldier fly variaties. Here’s a photo of that fly:

(unidentified fly - not bsf)

There are over 200 members of the soldier fly family (Stratiomyidae) in North American, but I assume the other soldier flies won’t work well for bio-composting.

I’m fairly certain some of the larger larvae feeding in the BioPod are black soldier fly larvae, so it shouldn’t be long before they become the dominant species.

Frog removal is becoming a daily chore. :/

AUGUST 2

I may have been too conservative with the food scraps added to the Pod so far. I’ve limited the food source to the original few cups of dry dog food put in at the beginning. Since there are larvae now present I decided to add more food today. When I removed the BioPod lid I was happily surprised to see 4 female BSF laying eggs. If they all survive that could be a few thousand larvae.  Two of them kept laying will I poured the sloppy scraps in.

AUGUST 10

Today there were prepupae in the collection bucket. Prepupal larvae (prepupae) are simply the mature, dark colored larvae that are in the final stage before they pupate and change into adult black soldier flies. Although the light colored immature larvae sometimes migrate out of the BioPod the majority are these prepupal larvae.

Above: The BioPod collection bucket

The number of larvae actively feeding in my new pod is steadily increasing as is to be expected. I’m short on food scraps so I’ve been feeding this colony a type of hog feed that is made from cornmeal. Ideally I’ll find a source of food waste to use but for now I don’t have the time to find it or fetch it. : /

SEPTEMBER 24

I haven’t had much to report since the past several weeks have been business (BSF composting) as usual. I add scraps every 2 or 3 days and I occasionally empty the collection bucket and liquid jar. I’m spending about 5 minutes per day with this unit on average. Most of the grubs have been fed to my pond fish, and some of them have been sent to my BioPod customers in seeding kits.

As the weather gets cooler I’ll monitor the activity of the female black soldier flies that visit the unit to lay eggs. I’ll probably start a new post to record the end of season information.

composter, compost, larvae, fly, flies, biopod