Mites in the Meal Worm Bin II

I wanted to provide an update on my mite infestation of my mealworms that I wrote about here.  This situation came about due to my increasing the humidity in my meal worm bin (as I had too dry of conditions prior and had die offs). Though the mealworms were happy, happy, happy it allowed for a mite population outbreak among all of my mealworm containers, despite my irradiating all of the bedding prior to putting it in. 

My strategy of divide an conquer combined with reducing humidity levels, seems to be working. I was reluctant to throw them all out and start over as I had come so far in my 1st generation cultivation and winter is coming.  I've abandoned temporarily my 3 drawer self sifting system for a setup to deal with my original occupants (beetles and worms) affected by this infestation.

I have four containers now since discovering the RAGING INFESTATION (mites covering everything to include outside the container like a large army) as follows:

  • Mite-infested beetle container 1:  this is my original beetle container.  They will be left to continue their life cycle. Mite infestation is greatly contained from original proportions, but still probematic.  Anything sifted from here goes to....
  • Mite-infested incubator container 2:  This contains (a) beetle siftings of eggs/frass (I no longer have my self sifting bin set up for this infestation) and (b) siftings from my worm bin (frass and tiny, tiny worms).  While tempting to just throw this out, there are so many worms/eggs in this mix, I just don't want to destroy them.  However, this container really has a mite problem. I wipe down the inside/outside of the container to remove the mites, and keep it away from my other two less infested bins.
  • Mite-infested worm container 3:  This contains worms of all sizes that don't fall through my fine mesh sifter in to #2.  I have a gold mine here, and I am keen on preserving them.  The mite infestation is mostly contained here largely because the sifting causes mites to fall out and stay in #2.
  • Clean container 4.  This container is in my office, away from the infested container.  I created this container from the occupants of #2 (worms and pupae).  I picked out the larger worms; washed them in a fine mesh strainer (dunked in water, rinsed off quickly with room temp water, and put on an absorbent towel).  There were NO ill effects to my worm friends.  Not one died, nor did they seem too disturbed by the process.
    • Worms will go to pupae stage and pupae from #2 are given same wash, rinse and dry and placed here.  Eventually, this bin will be all beetles, and will be placed in the self sifting bin.  
    • This bin will be the genesis of the 2nd generation, mite-free colony.

Mites in Mealworm Bin

In doing my research on starting a mealworm colony, I noted that grain mites can be a problem.  To avoid this catastrophe I dutifully microwaved the bedding substrate.  No problems.  When my last batch of mealworms ordered suffered an inordinately high rate of die off, to include the pupae which had about a 33% mortality rate, I increased the moisture.  My mealworms were fantastically happy.  However, this past weekend, seemingly overnight, I had a mite infestation.

In checking on my mealworms, I noted  webby stuff in a coffee filter basket (which I used for the water crystals.  When I looked closer, I realized that the bins were covered with fine white, moving mites.  Clearly, this was not a minor battle, but those little buggers (spiders actually) were in full siege mode.  They were crawling EVERWHERE.  And even though I had taken precautions and had separate bins, all of them were contaminated.  (Now I realized why I felt crawly things on my arms a few times last week after checking on mealworms.)  When I checked my wheat bran bag, (in the garage and far way from the colony, that was contaminated.  So clearly microwaving (or microwaving the way I did it) was not 100% effective.  However, I also introduced some brewer's yeast + I increased the humidity level quite a bit + I had some vegetable matter, so the source of the infestation could be manifold

I wasn't about to throw it all out.  Too much painstaking work went in to raising this first batch of worms which were now at feeding size for my bird customers.  Plus, I need to get pupae to replenish my 1st generation beetles who are running out of steam.  Here's how I'm choosing to handle--and I'll update on results.

  • took all bins outside.  I had a bin with incubating eggs worms and a large bin with more mature worms.  Beetles are still doing their thing.
  • sifted worms out but could not sift out all bedding.
  • Cleaned the containers with soap water and then a final rinse of bleach (and final rinse)
  • Put the worms (and their contaminated bedding into one of the bins).  
  • Began a process of  creating an isolated colony of mite-innoculated worms.  
    • I picked out individual worms in the contminated bin (but still less so) and gave them a wash off. That sounds crazy, but it worked. I simply put the worms in a fine sieve strainer, immersed it in water, and then rinsed under tap.  I then put them on a paper towel.  They did not appear uncomfortable, and they are thriving and happy.  None have died.  I was gentle, but they likely felt briefly water-boarded.

 I'm continuing to let the mite-infested colony exist with periodic harvesting for feeding the birds as well a a 'wash up' to increase the non-invested colony for development to pupae. For the mite-infested colony, I have deployed these strategies:
  • Put a band of vaseline around the top boarder of the bin to keep the mites from migrating out.(I found this helpful hint on the web)  (PS:  this does not work well)
  • Wiping down the sides of the bin with a vinegar soaked sponge to capture and destroy the hundreds and hundreds of little moving white dots. 
  • keeping the humidity level lower.
Though not an insignificant amount of works, my customers love it.  While waiting for my mealworms (1st generation) to mature to eating size, my customers went away.  That was fine as there were no nestlings/fledglings at the time.  Now that I'm back in the feeding business, the Carolina Wrens are feeding fledglings, and I have some Bluebird juveniles (3) that are coming to the feeder with a female.  I'm wondering if they are from the last fledge from the nest box.  And, my Summer Tanager girl has come back.  I have missed her.  Though, the bluebirds (even the juveniles) are very inhospitable.