Mealworm farming

[sueblack]

Does anyone know what level of humidity is needed for a mealworm colony? Now that the season is changing I seem to have a lot of dead worms and pupa in my mealworm farm which is kept in my garage. I have seen some say they mist water on a paper towel in their pupa drawer. Do any of you do this and would this help with pupa dying?

 

[Gallo del Cielo]

Does anyone know what level of humidity is needed for a mealworm colony? Now that the season is changing I seem to have a lot of dead worms and pupa in my mealworm farm which is kept in my garage. I have seen some say they mist water on a paper towel in their pupa drawer. Do any of you do this and would this help with pupa dying?

I've read studies that suggest that they do best around 60-75% RH. Having said that, I wouldn't add any moisture beyond that contained in vegetables. Low humidity is almost certainly not the cause of the mortality you're seeing and adding moisture will inevitably lead to catastrophe in the colony. The larvae have specialized organs in their behinds that draw moisture directly from the air and the pupae are very resistant to desiccation. I live in one of the driest places on the planet (this is the humid season here and the humidity is 25% right now) and I don't have these kinds of issues. Generally, I would look to diet for answers. Failure to complete metamorphosis is often related to something lacking in the diet or something inhibiting development. Do you have them on wheat bran or oats? Are you washing the vegetables well before feeding them or feeding organic? Finally, I wonder about the source of your stock. Sometimes distributors will treat mealworms with juvenile hormone which inhibits metamorphosis (they're often sold as giant or super mealworms). Depending on the dosage they got, you can see lots of mortality in the older larvae and pupae. Sometimes they will pupate and complete metamorphosis, but they generally don't reproduce. Besides the pupal deaths, do you have many that are turning into beetles?

 

[Lacy Blues]

I've read studies that suggest that they do best around 60-75% RH. Having said that, I wouldn't add any moisture beyond that contained in vegetables. Low humidity is almost certainly not the cause of the mortality you're seeing and adding moisture will inevitably lead to catastrophe in the colony. The larvae have specialized organs in their behinds that draw moisture directly from the air and the pupae are very resistant to desiccation. I live in one of the driest places on the planet (this is the humid season here and the humidity is 25% right now) and I don't have these kinds of issues. Generally, I would look to diet for answers. Failure to complete metamorphosis is often related to something lacking in the diet or something inhibiting development. Do you have them on wheat bran or oats? Are you washing the vegetables well before feeding them or feeding organic? Finally, I wonder about the source of your stock. Sometimes distributors will treat mealworms with juvenile hormone which inhibits metamorphosis (they're often sold as giant or super mealworms). Depending on the dosage they got, you can see lots of mortality in the older larvae and pupae. Sometimes they will pupate and complete metamorphosis, but they generally don't reproduce. Besides the pupal deaths, do you have many that are turning into beetles?

I didn't even think about that. Guess I better make sure I wash the food really good. Poor little bugs! Thanks for saying that Gallo.

 

[sueblack]

Quote:
Thank you for your response. I am using wheat bran. My container is of larger worms I have been allowing to pupate. I have been trying to harvest the last ones without adding more wheat bran because the tub needs emptied. I also have a reptile heating mat under the container. I suspect the worms must not have enough wheat bran left to finish growing. Its hard to tell how much bran is left because I'm digging through it looking for pupa. I will add more bran tonight. I suspect the heating mat isn't an issue, since the nights here have been in the 50's and I have been putting fresh carrots in every other day. Thanks for your input.

 

[blackswamp]

I'm getting a lot of moisture in one my plastic bins.

I got several bins & One of them has most of the Beatles in it & it has been getting moister in there.
Do you think I got maybe too many Beatles in there? The lid has plenty of holes & there is holes on the side for air.

 

[gaitngirl]

After a few setbacks my 2 colonies are doing quite well. I am doing a 3 drawer system. I have 2 separate larval bins going - 1 from my original 200 locally purchased mealworms and 1 from a larger quantity purchased online. The smaller, original colony is now 2nd gen and starting to pupate. The mealies that hatched from the beetles from the 2nd colony are growing well and I should start seeing pupa in another month or so.
Here are pics . . .

There are hundreds of beetles under the newspapers, too.

 

[kwol]

To kwol and others who use a screened drawer to babies and eggs to fall through: Do you use window screen? Do you find that most of the babies and eggs drop through the screen into the next drawer? And what do you use for bedding in the top drawer? If you use wheat bran, does most of it fall through the screen?

I use metal mesh window screen. I read somewhere the beetles could eat through a cloth mesh and that made sense to me. DH and I went to Lowe's and bought a roll of it for around $6.00 I think, and DH cut the bottom of the drawer out, cut the mesh and glued it on for me. Cut the mesh bigger than the hole but you do need to lay it inside the drawer, otherwise the drawer won't slide.
I am using laying mash pellets in the beetle drawer. The pellet dust, eggs and beetle waste fall through to the mealie drawer. It has been about 10 months since I began and I only last week decided the mealie drawer was getting too full and I sifted out all the larger mealies and put fresh substate in the mealie drawer. This time I am experimenting by using pellets in the mealie drawer too, instead of the pellets I had ground up in the food processor. It seems to working so far. I am still getting pupae and have not found dead mealies. I was thinking I can pick out the carrot remainents better this way.

 

[jimmywalt]

I purchased 500 mealworms form Petco in July. Have them all in a 10 gallon aquarium. All have turned to beetles........ So the question is....... How long before I see little worms from the eggs the beetles should be laying?

Seems it's been a couple weeks since I saw my last pupa..... I just have boat loads of beetles. Hopefully this will pay off soon.

Thanks.

 

[chrissyr]

After a few setbacks my 2 colonies are doing quite well. I am doing a 3 drawer system. I have 2 separate larval bins going - 1 from my original 200 locally purchased mealworms and 1 from a larger quantity purchased online. The smaller, original colony is now 2nd gen and starting to pupate. The mealies that hatched from the beetles from the 2nd colony are growing well and I should start seeing pupa in another month or so.
Here are pics . . .

There are hundreds of beetles under the newspapers, too.

Aww, so happy for you! It's a process that seems to take time, so it's nice when it all goes well.

 

[sillybirds]

I purchased 500 mealworms form Petco in July. Have them all in a 10 gallon aquarium. All have turned to beetles........ So the question is....... How long before I see little worms from the eggs the beetles should be laying?

Seems it's been a couple weeks since I saw my last pupa..... I just have boat loads of beetles. Hopefully this will pay off soon.

Thanks.

You'll usually start seeing tiny tiny mealworms by 4-5 weeks after the beetles start laying eggs. They are initially very small and barely visible to the naked eye.