Mealworm Behavior

[Chris52]

Hello! I decided that it would be a fun project to attempt to raise mealworms into beetles and maybe try to breed them (not for another animal's food), so I picked up 50 from my local pet store. I currently have them housed in a standard plastic shoebox with about an inch of oats as substrate. I make sure they always have a slice of apple or two for water and I replace it every few days. I have now had them for about two weeks. I noticed recently that several of the larger mealworms have been staying at the top lately, instead of burrowing like they have been. Are they getting ready to molt or pupate? Also, for future reference, can the beetles climb plastic and/or escape from the container? I would also appreciate any tips on how to raise the mealworms or breed the beetles. Thank you!

 

[Jacob Ma]

They could be getting ready to pupate if they are a bit round and laying still in a C-shape. Beetles cannot climb slick plastic walls, but if your plastic has many scratches inside, then they may be able to clamber out.

Mealworms can pretty much be cared for the same way throughout their lives. They can adapt to a variety of conditions, and breeding should be no more difficult. Spraying the soil very lightly every once-in-a-while should encourage some egg laying and as long as the container doesn't completely dry out, the eggs should hatch properly.

 

[Chris52]

They could be getting ready to pupate if they are a bit round and laying still in a C-shape. Beetles cannot climb slick plastic walls, but if your plastic has many scratches inside, then they may be able to clamber out.

Mealworms can pretty much be cared for the same way throughout their lives. They can adapt to a variety of conditions, and breeding should be no more difficult. Spraying the soil very lightly every once-in-a-while should encourage some egg laying and as long as the container doesn't completely dry out, the eggs should hatch properly.

Some of them are curled up in a C-ish shape, but when I take the lid off of the container, they immediately burrow or start squirming. How long do they pupate? And are you saying to spray the oatmeal? It just seems a little odd. Thank you!

 

[Tenevanica]

I don't know where you got your mealworms, but some of the larger brands that sell mealworms just for food will inject their larvae with chemicals to prevent the from pupating. Did your larvae come in a plastic container?

 

[Chris52]

Yes, they came in a plastic container. I got my mealworms at Petland (a rather large pet store around here), but the package on the cup the mealworms came in says that they are from Bug Co. On their website it says that they are "raised in a completely organic fashion", so I am not sure.

 

[Tenevanica]

Yes, they came in a plastic container. I got my mealworms at Petland (a rather large pet store around here), but the package on the cup the mealworms came in says that they are from Bug Co. On their website it says that they are "raised in a completely organic fashion", so I am not sure.

I'd imagin that Bug Co. would be preventing pupation, but if they truly are being raised in an "organic fashion" then they should pupate. I guess time will tell.

 

[lunarae]

Just gonna say they can take forever. I did the same thing as you and it took months and months and more months before I ever saw little mealworms after I finally got beetles and it took forever to get beetles originally as well. However, when you do get them there will be a ton no doubt.

So long as they are in fact mealworms and not superworm. Superworm are a whole different ball game when it comes to trying to get them to pupate.

 

[Chris52]

I contacted Bug Co. and they said that their regular mealworms are not treated to prevent them from pupating. Also, yesterday morning I found two mealworms that look strange. What is happening to them?

Just gonna say they can take forever. I did the same thing as you and it took months and months and more months before I ever saw little mealworms after I finally got beetles and it took forever to get beetles originally as well. However, when you do get them there will be a ton no doubt.

So long as they are in fact mealworms and not superworm. Superworm are a whole different ball game when it comes to trying to get them to pupate.

About how long did it take for you to see beetles? Thank you!

 

[lunarae]

Those are pupae. And I think it depends on how warm it is how fast it will be. It took forever for mine to get to pupae stage but then I want to say it was only a couple of weeks before beetles. It's the time between getting beetles and seeing new worms that takes forever because they start out so small you can't see them.

 

[Chris52]

Those are pupae. And I think it depends on how warm it is how fast it will be. It took forever for mine to get to pupae stage but then I want to say it was only a couple of weeks before beetles. It's the time between getting beetles and seeing new worms that takes forever because they start out so small you can't see them.

YES!!! I found about six more like that this morning. Also, I have seen multiple tutorials on "breeding mealworms" that say to separate the mealworms, the pupae, and the beetles, and rotate their substrate every few weeks. Is this necessary to breed them? I only did this for fun, so I am not going to do anything too special to get them to breed. Thank you!

 

[lunarae]

YES!!! I found about six more like that this morning. Also, I have seen multiple tutorials on "breeding mealworms" that say to separate the mealworms, the pupae, and the beetles, and rotate their substrate every few weeks. Is this necessary to breed them? I only did this for fun, so I am not going to do anything too special to get them to breed. Thank you!

You can do that if you want, but I honestly don't find it necessary. If you had super worms it would be needed but meal worms no. I have an bin half way full of oatmeal that I have all of them together in and they do just fine. I am about to go through and sort them, get rid of dead bugs and the like and give them new substrate but it's been months since I've bothered with that. You want to change the oats out occasionally cause of mold and such but you don't have to separate them.

I will say though I did go a time without providing them with anything other then the oats. Because of that I did have beetles that didn't develop well. Wings were mangled, and their backs seemed eaten through. After going back to providing carrots regularly for moisture this stopped so I do think that the worms will feed on the beetles or pupae for moisture if there isn't enough provided. Something to be aware of. At least I think that was it. Or it was because they didn't have enough moisture when they went into pupae stage they didn't develop fully quite right. Regardless, it's important to provide something like carrots and such occasionally. Only trouble is eventually moisture will lead to mold and that leads to substrate changes. Which like I said the babies start out microscopic so every time you change substrate chances are your tossing out young offspring you can't see.

That alone could be why people do the separating thing, so that the bin with the newly developed offspring doesn't get tossed as much. There are some pretty easy and simple ways to do these bin set ups to where they are self sorting between beetle and baby worms. I set one of these up myself before I just tossed them all in one bin to conserve space but I may go back to that now that I think about it. I don't know, I'm going to be spending today sorting through my bin separating beetles from pupae from worms to see what all I actually have and to change out substrate so...we will see. But I started my breeding project early spring last year and it was late winter before the babies got to where I could see them.

 

[lunarae]

Here is an example of just how tiny they can be. That is not how they start out, that's simply the smallest I could find and actually dig out of the substrate. Usually you can tell you have babies because even after you move the substrate off the bottom by pushing it to the side, you can see kinda like dots moving around in quick little motions. Least I think that's them.
The next is an example between one that's just pupated, and one that is literally just about to emerge as a beetle. It's squirming and everything right now getting ready to come out. So you can see the color difference.
Then below is one of the beetles having just emerged, and then another that's finally darkened all the way. They start out white/cream colored before slowly darkening to black. Though I have had some never fully darken to black and tend to be more like a dark brownish color.

 

[Chris52]

YES!!! The pic is bad, but I found my first beetle today!

 

[Chris52]

Looks like there are several more pupae ready to emerge too!

 

[Jacob Ma]

I would be careful so that the beetle or the mealworms don't try to eat the soft-bodied molting beetles. Try leaving a piece of fresh food out for them.

 

[Chris52]

I would be careful so that the beetle or the mealworms don't try to eat the soft-bodied molting beetles. Try leaving a piece of fresh food out for them.

I make sure they always have a few apple slices?!?

 

[truecreature]

I keep my beetles well hydrated but they still like to cannibalize fresh pupae and eat the soft body out of other beetles whose wings are askew. So what I do is just remove any pupae that I see and keep them in a separate container.

 

[Jacob Ma]

I make sure they always have a few apple slices?!?

Naturally, the beetles live in rotting wood so they have a little bit of protection from getting cannibalized by one another. It's understandable that you would continue to supply the insects with fresh apples, but remember that these will eat just about anything so they need a bit of space.