Worried that BSF cannot escape new fangled composter

[lulu_bopeep]

I am new to both the worlds of forums and BSF, so please excuse any ineptitudes on my part.  I'm not even sure this is an appropriate place to ask this but.......

Last month a neighbor started complaining of giant maggots in her compost after heavy rains and a visiting mother who added gobs of wet veggie matter to her barrel composter and neglected to add any browns or dry matter.  I didn't think too much about it though until I found the same creatures in my brand new composter I'd only started 2 weeks earlier.  This composter is a giant ball with hollow internal posts that provide air flow and help to mix the contents when the ball is rolled (you can view it here http://www.compostbins.com/compost-bins/compost-tumblers/ecomposter11cubicftcomposttumbler.cfm) in case I'm not explaining well.

Now that I know that these are BSFL, I am "in love" with them and want to maintain a colony. But I am worried that the mature larvae are trapped inside the composter as there is no easy access to get out since the air holes are in long poles that don't always contact the matter and don't necessarily lead "up and out".  I intend to purchase a BioPod eventually but am preparing for a summer trip and don't have time to deal with set up and maintenance in my absence.

So in the mean time are the mature larvae going to die and rot inside the composter?  I'm considering dumping out the compost (basically all that's there now is  BSF larvae and yard waste since they've eaten all the fruit/veg)  that's in there so the larva won't expire as there are not any perpetual dry spots for them to pupate since the ball is supposed to be rolled regularly.  Also, am I killing/crushing some just by rotating the ball?  How sturdy are they?  I'd appreciate any suggestions. 

Also when I return from travel and am ready to start a BioPod colony, can I keep them from also invading the ball again?  I know they are just larvae , but I'm troubled by the thought of large numbers of them expiring because their mother had the poor planning to lay them in a contraption they could not escape from.

[GW]

Hi lulu_bopeep! So far you're doing fine with the forum etiquette and I applaud your thoughtfulness about the BSF.

The design of the ecomposter certainly isn't the friendliest for BSF, but I think there may be some things you can do to accommodate your new grub friends. I wouldn't worry about rolling the composter because BSF grubs are pretty resilient. If you cut the food scraps into smallish pieces (no 1/2 watermelons) the BSF should be fine.

There are a few things you can try that might help the grubs escape the composter. The first thing that came to mind is to leave some of the air tubes off, something like 2-8 of them. That would give the grubs more direct access to the outside and I don't think it would compromise the effectiveness of the composter much. If that doesn't seem to work you could also open the smaller lid of the unit for a few hours every 2-3 days. Of course the opening should be towards the ground as much as possible so the grubs don't have to crawl up the wall at a steep angle. (If there is condensation on the inside walls of the composter the BSF will be more able to crawl straight up.) If you ever wish to collect the light colored juvenile grubs from inside the ecomposter there are methods for that which we can discuss later.

If you do eventually culture BSF in a BioPod I think you will find far fewer grubs appearing in the ecomposter. BSF females are strongly attracted to a concentrated colony like the kind you can maintain in a BioPod.

It's very nice that you're concerned about the BSF in the composter. Please let us know if you need more suggestions to get to a point where you're comfortable with it.