Black Soldier Fly Larvae

[GaryD]

Hi Justafarmer,

BSF are likely to be found almost anywhere in Australia. It is believed that they were translocated to Australia from the US during World War II.

While there are many species of Soldier Fly throughout the world (some of which are native to Australia), it is the Black Soldier Fly (Hermetia Illucens) that has attracted the attention of researchers for its potential use as animal protein for livestock.

Gary

[justafarmer]

Hi Gary,

So, from what I have gleaned from the posts and your site, all I have to do is make some holes large enough (say 10-15 mm) in the side of my regular compost bin (presumably in the upper third of the bin) and the BSF female will in time lay eggs in the compost and mature to the stage that the larvae then climb out if I provide an incline out of the material?

I read somewhere that the ideal temperature for these delightful creatures is 27-30 degrees. Can I expect colonization of my compost bin even here in the cool temperate climes of Melbourne? It's nice and warm now in December, but what happens in the middle of Winter when the daytime max can be 8-10 degrees?

Has anyone managed to culture these things in Victoria?

[Murray]

Hi Justafarmer,
I live about 20kms south east of Gary. Last summer I obtained some live larvae from Gary and put them in my compost bin. Had a good colony until winter came and they disappeared. They have not come back even though I have a really good bin going. I live on 10 acres with acreage blocks all around me. I can only assume that because of the bush environment they are just not in my area.

[GaryD]

Hi,

Our flow of BSF larvae has been a bit slow lately. My little harvesting rig is only yielding a few each day at the moment. The problem seems to be a shortage of sufficient kitchen scraps.

GaryD

[Martin A1]

Hi Gary & Everyone,
I have had two "lots" of BSF in my compost bin this summer. I've been meaning to take some photo's but I figure if you have seen one BSF maggot then you've seen 'em all.

My attempts to harvest them effectively have not yet succeeded. Sorting them by hand and watching the fish enjoy was fun once but not again.

I tried a set-up like the one Gary described earlier in this thread using my old recycling 'box' from local council. My experience was that the BSF simply dug themselves to the bottom of the tub ignoring my available PVC pipe ramps. Persistence and some further inspection some two weeks later found many apparently dead (or matured) in the lower layers.. but they hadn't crawled up any ramp??

An observation of them on the top of my compost heap today indicated that after about 5 mins with the lid off the compost bin they quickly 'disappeared from view'. It seems that they do not like light!

A quick read of this months newsletter had another article on BSF from "Guru" Gary which showed an enhanced harvesting set-up that takes advantage of the larvae's apparent dislike of light.

Guru, can you clarify for me if harvesting BSF larvae is dictated by
(a) the larvae reaching a level of maturity and then wanting to march up hill; (my original understanding).. OR
(b) them simply avoiding the light of day and being prepared to march up hill to do it at any stage... OR
(c) all of the above ie they will march up hill when mature but only if it is dark?

Figuring this out will really help my current lack of BSF harvesting capability I think. Thanks mate.

PS How do you know when they are mature? Any tell tale looks, age or behaviour?

[GaryD]

Hi Martin,

a) the larvae reaching a level of maturity and then wanting to march up hill; (my original understanding).. OR
(b) them simply avoiding the light of day and being prepared to march up hill to do it at any stage... OR
(c) all of the above ie they will march up hill when mature but only if it is dark?

When the larvae are ready to self-harvest, they will be about 20mm long and dark in colour and they'll walk up an improvised ramp of their own accord. This happens at night.

You can manually harvest them at any time using the light extraction method that small-scale worm farmers employ. You mount a desk lamp or other strong light over a bench and put a shovelful of larvae-ridden compost on the bench and brush away the compost a bit at a time. They don't like light and will either bury themselves into what remains of compost or they start to leg it. When I've harvested this way, I've used a pair of long tweezers to pick them up and deposit them into a container. This is a bit labour intensive for me but it will get you some larvae in a short time.

I've also made up a smal table top harvest rig which comprises two plastic trays. I've cut a slot in one end of one tray which I rest on the edge of the other tray to form a ramp. I put a couple of handsful of concentrated larvae and compost into the sloping tray and then I disturb the compost and they'll start to march up the ramp. Making something like this is very easy.

Photo 1 - My current harvesting rig.
Photo 2 - Harvesting by the light extraction method.
Photo 3 - When there's nowhere to hide, the larvae will simply leave.
Photo 4 - My table top harvesting rig.
Photo 5 - The larvae as they exit the ramp - they just jump into the collection tray.


Gary

[GaryD]

.....and when it all goes well....


By the way, while we've spoken about using BSF larvae for fish, your chickens will absolutely love them. If I throw a handful of the frozen larvae into the grass, they'll track down every single one of them. The leathery skins on the larvae will pass through your fish undigested which can be a nuisance with keeping a small tank clean. Because of the way that chickens process their food, this is not an issue for them.

Scientists in the US have used BSF (35% fat content) to extract the oil to make bio-diesel. Any remaining fat or skins would make a good fuel if pressed into a cake like they do with olive seeds and skins.

[mtnester]

Hi Gary etc
just getting info together to kick off my first attempt at IBFP.
With trying to attract BSF to say horse manure how would you discourage ordinary blowies and house fly, so you end up with mainly just BSF.

[GaryD]

Hi,

You don't have to do anything in particular. Once BSF find the conditions that suit them, they will assert themselves. It will be the sheer number of them.....and their voracious appetite......that will displace other fly species.

If things are slow with the horse manure, you might try spreading some milk or some food scraps across the manure. BSF get really interested in things that stink.

GaryD

[hygicell]

quite a sophisticated harvesting rig!
could it be possible to have a ramp right out of the composting bin and straight up to the fish tank?
would avoid all manipulation

and do BSF and worms live together in peace?
can they be combined?

Frank