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Uitert size Want an easy (and free) way to feed your chickens? Have you heard of black soldier fly larvae? Not sure what the big deal is? In this article, I’ll show you how to get started growing black soldier fly larvae—and why they’re a valuable food source for your flock. You’ll also get our free plans for building your own black soldier fly larvae farm.
What are black soldier fly larvae?
Black soldier fly larvae are the state of the black soldier fly (tightly shining). The adults look like wasps, and the larvae may remind you of mealworms. But don’t confuse them — black soldier fly larvae and mealworms are different species, with different advantages to backyard chickens and ducks.
Since they can be found all over the United States, especially in the southern states, you probably already have black soldier fly larvae in your backyard! Don’t worry if you never spot them. Flies are easy to miss. We never realized they inhabited our ranch until some horse grain was left in the bed of our truck during a rainstorm. A few days later, hundreds of caterpillars crawled out of the grain. We accidentally lifted them in the bed of our truck! Yes, it was pretty gross, and it made me realize how easy it is to farm these insects. We had some happy chickens that day.
Black soldier flies everywhere. You just need to create an attractive area for the adults to lay their eggs to start your own black soldier fly larvae farm.
How do I feed them to the chickens?
You may be wondering why these insects are so healthy for birds. While adults are not generally fed chickens, their larvae make an interesting, nutritious, and free supplement in your flock’s diet. The larvae of the black soldier fly contain about 50 percent protein and are a rich source of vital nutrients, such as calcium. Since protein is needed for feather development and egg production, it’s obvious how beneficial these tasty foods are for chickens. The extra calcium helps your flock lay better eggs, too.
There is no exact percentage of how much in your flock’s diet can be substituted for black soldier fly larvae. Just make sure your chicken is getting all the nutrients it needs. You can start by substituting 10 percent of the regular flock grain, and then increase from there. They will thank you! It’s always a good idea to consult your vet as well.
To feed these insects to your flock, you have a few options. Could you:
- Feed the live insects
- Freezing larvae (thaw before feeding)
- Dry the larvae for long-term storage
Each option has advantages. Feeding live insects is fun and exciting for your chickens because it allows them to indulge in their natural behaviors. Our birds are carnivores. It evolved to feed on and hunt for tasty insects. Since we keep them locked up all day, they get a little bored! Live insects break up boredom and give your flock a little exercise.
Eventually, the live black soldier fly larvae will transform into an adult chrysalis. Mature black soldier flies will stop reproducing as summer wears off, and you won’t have any more caterpillars to harvest until the following spring. If you don’t harvest and store some youngsters, your stable stock will eventually dwindle.
Feeding dead black soldier fly larvae makes it easier to mix them into the feed. It is also easy to keep dead larvae for long-term storage (either by freezing or drying them). If you don’t want to keep black soldier fly larvae in the freezer, you can freeze-dry them after they die. Use a solar oven or even a home oven to dry them for long-term storage. Another way to dry black soldier fly larvae is to heat them in the microwave, however, I have never personally tried this method.
Plan a DIY black soldier fly farm
Now that you know why these insects are so healthy for your chickens, let’s talk about how to raise them yourself! First, you will need a home for your caterpillars, and one way to do that is to build your own.
Building your own black soldier fly larvae farm only takes a few minutes. And it doesn’t need to cost an arm or a leg. We spent less than $20 on this project and were able to recycle wood waste and sawdust from our barns to complete it.
To make this project easy and accessible to chicken keepers of all levels, we used a 55-gallon plastic container. You can buy them at any major store. While plastic may not be for everyone, we wanted to show how easy, accessible, and low-cost this project can be.
If plastic is not your thing, you can also create boxes out of wood using the same design. It will cost you a little more than a plastic container, but it will last you much longer. If you are not sure that raising black soldier fly larvae is right for you, stick to a plastic bin. You’ll be less financially invested in the project, and you can always upgrade to a wood crate later.
Ultimately, the goal is to grow a protein-rich feed for your chickens. Since the design works so well with so many different types of materials, feel free to use wood, cement, cinder blocks, or whatever else you have on hand.
For this project, you will need:
- Cinder blocks, or another way to lift the container ($1 each)
- 55-gallon plastic bin and smaller plastic crate ($14 total)
- Practice with a small circumference (1/4 inch is best)
- mattress topper (free)
- Starter feed (such as ground corn, spent fruits and vegetables, horse feed, rice bran, etc.).
- Corrugated cardboard (free from post office)
- Two pieces of wood at least 6 inches wide (the best width) and half the length of a trash can (free)
Total cost: $18
Step 1: Stack the ash cubes and the bin.
Assembling your trash is easy. First, drill a few holes in the container for drainage, so its contents don’t become soggy. Next, stack your cinder blocks so that the box is raised off the ground. This is important for two reasons: First, it keeps mice and rats out of the trash. Second, it creates good circulation around your trash. You don’t want the inside to get too hot, as it will cause the food to rot faster (attracting the wrong kind of bugs). Additionally, if your box gets too hot, it will cause black soldier fly larvae to crawl out sooner. It will be smaller and less nutritious for your chickens.
If you have another way to raise your trash, such as an extra workbench or saw, you can use these in place of ash briquettes. The idea is to just get the trash off the floor.
Step 2: Add your bedding substrate to the box.
We used spent shavings from our chicken coop. We didn’t want the inside of the trash can to get too wet. The moist, anaerobic environment causes food to rot quickly, and attracts houseflies rather than black soldier fly larvae. Some other bedding options are newspaper, wood chips, compost, or dirt.
Step 3: Add your splash feed.
We used rice bran for this project, and tossed it on top of the rice shavings. Then we wet the bran a little so that it creates a scent that attracts the black soldier flies.
Step 4: Attach it to the cardboard.
Just place the cardboard over the feed. The black soldier fly ladies will know what to do!
Step 5: Add the Planks.
Place them in the trash, and rest them side by side on one side of the bin so that they are on a shallow slope (at least, as shallow as the bin will allow). The idea is that these panels provide an easy way for the caterpillars to crawl out of the box. It’s still possible that some caterpillars will crawl up the sides of your box, but most will use the path of least resistance. If you notice a lot of caterpillars crawling around the sides, you can catch the caterpillars by placing additional, smaller boxes under those areas as well. You can also add a lid to your trash can to help contain and protect the larvae and their habitat.
If you have strong winds like we do on our farm, weighting the cap with a cinder block will prevent the cap from getting loose. This is especially important in storms, because you don’t want a lot of water in the trash. Too much moisture may drown the caterpillars, cause them to crawl out too early, or attract the wrong kind of insect.
Step 6: Place the extra trash directly under the planks.
Keep them as close to the ends of the boards as possible to ensure your larvae can reach the receiver box. If you need to raise the receiving box, just use extra cinder blocks, or something similar. Check your small container daily! Adult black soldier flies only live for about 7 days. At that time, they need to mate and lay eggs. The eggs take about 4 days to hatch, so you should see results quickly.
Step 7: Choose a location for your container.
You don’t want the inside of the trash can to get too hot, too wet, or too wet. If none of these conditions are ideal, it can lead to faster crawling and possibly death. While the goal is to harvest caterpillars to feed our chickens, you don’t want them to die early in your bin or crawl out before they are big and nutritious for your birds. Choose a spot that’s in partial shade and can keep your trash reasonably dry. It allows you to build your own caterpillar farm in a basket and easily transport it if needed.
Whenever we decide to start a new box, I look for a place where I’ve seen maggots in the past. For example, our horses are adept at throwing their grain and mashing it in the mud. If we dig an inch or so into the heel of our shoe and see black soldier larvae, we know it’s a great place to put a new basket. Flies are actually attracted to that area! You can also place a trash can near your coop. Black soldier flies are attracted to the smell of chicken feed, so they are likely to be in that area already.
Maintain your trash and attract black soldier flies
Now that your trash is complete, go to the next step!
Your goal is to attract mature black soldier flies and encourage them to lay eggs in your trash can. These insects naturally lay eggs near their food source. However, unlike house flies, which lay their eggs on me Their food, black soldier flies lay their eggs near their food. So, it is important to provide an attractive placement site, such as corrugated cardboard. Any cardboard will do, although personally I would stay away from anything with a lot of ink and printing on it.
For food, we use ground corn, rice bran and wheat in our bins. We already have it and are unlikely to attract houseflies. We also save leftover fruit and vegetable peelings and other kitchen waste. Experts advise avoiding putting meat in the trash. When the meat decomposes, it gives off a moldy smell, which is likely to attract houseflies. We personally don’t like the smell, so we just stick to grains, fruits, and vegetables. We’ve always had great luck with cereal in particular!
Add food as needed, and keep an eye on the amount of food in the bin. If you notice it goes away daily, add more. If there is a lot of uneaten food in it, stop adding more. While you’ll want to use leftovers from your kitchen rather than using very fresh produce, you also don’t want moldy food creating an anaerobic environment in your trash. It will attract maggots rather than black soldier fly larvae. It’s a balancing act, but you’ll get to it soon.
How to harvest black soldier fly larvae
As they mature, the black soldier fly larvae will increase in size until they are black and about 1 inch long. At this point, they will begin to crawl in and out of their litter box to move on to the next stage of their lives. They are very easy to harvest as they will naturally leave the trunk. Simply wait for them to crawl!
Wood pallets give them an easy way to leave their nest. As they crawl, they will eventually reach the end of the boards, and fall into the receiving box below. You can check the box every day for new caterpillars. You can then decide whether to feed them to your flock right away or sacrifice them by freezing them.
Breeding and harvesting black soldier fly larvae is relatively easy and, over time, can provide a healthy, nutritious source of food for your chickens.
Maat van Uetert is the founder of the backyard chicken and duck blog, Pampered Chicken Mama, which reaches nearly 20 million backyard poultry enthusiasts each month. She is also the founder of Living the Good Life with Backyard Chickens, which carries nesting grass, feed, and treats for chickens and ducks. You can follow Maat on Facebook and Instagram.
Originally published in Community chicken Website 2019.