Experiment F01: A Shot of Flies

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Malakyoma

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Purpose: To determine whether or not "mini" D. melanogaster and D. hydei cultures can be successful. The use of such cultures would be to feed ooth hatches by placing the entire miniature culture inside the hatching enclosure.

Hypothesis: Cultures will ultimately be successful, yet limited by space, producing a smaller number of flies than the typical culture.

Method: 5 12oz cultures will be produced using the same media and different starting conditions.

Starting conditions:

Cup 1: moderate depth of media, 1 burst melano (approx 20 flies) initial population

Cup 2: moderate depth of media, 14 hydei initial population

Cup 3: deeper depth of media, 1 burst melano (approx 20 flies) initial population

Cup 4: deeper depth of media, 14 hydei initial population

Cup 5: moderate depth of media, 5 hydei initial population

Results will be recorded and posted here as evidence to support/deny hypothesis. Conclusion will be written at the end of production cycle.

The cups with media and excelsior:

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How the lids fit into place easily:

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Starting conditions:

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Begin Test

 
I've tried that a few times. It worked okay, but most of the flies tended to leave the culture or the culture dried out too fast. I think you will have to control for both in order for it to be a continuous source of flies for little mantids. Drying out will be an even bigger factor due to how little medium is used. Fruit flies used to be raised in those tiny fruit fly vials and did well so I don't think the size of the cultures will matter in regards if they're successful or not. They just won't last as long as a larger one.

Where are your testable predictions? :)

 
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For a controlled test you need to keep the ff cups all at the same conditions, same viv temps, humidity and day/night cycle because its proven ff produce more in the dark. Also Hydei usually require a more nurtient rich media to produce well and they take almost twice as long. Also not much you can rely on without knowing the amount of males vs females as well as their ages going in the culture because if all are different you wont have evidence on which does better really. I'd start with making the media a bit more runny for sure to prevent it from drying out. Then I would look for a setup that will make it easy to put them in the nymph enclosures without crushing a hoard of nymphs its not easy when you have an entire hatch in a cage to heard around out of the way.

 
I'll be interested in hearing the results. Here's my thinking. You only need a large FF culture when mantids are young. When they get bigger, you switch the mantids over to bigger feeders. However, it would be nice to be able keep a small "maintenance culture" of FFs around for the next generation of mantids. That would be more cost effective than letting the culture die out, and buying new FFs at a later time.

 
I've tried that a few times. It worked okay, but most of the flies tended to leave the culture or the culture dried out too fast. I think you will have to control for both in order for it to be a continuous source of flies for little mantids. Drying out will be an even bigger factor due to how little medium is used. Fruit flies used to be raised in those tiny fruit fly vials and did well so I don't think the size of the cultures will matter in regards if they're successful or not. They just won't last as long as a larger one.

Where are your testable predictions? :)
I hadn't considered having it produce for a long time in the enclosure, my thought was more to have a few of these producing at a time with a small initial population and put them in the enclosure when they're exploding. The mantids eat the now free flies, and when there aren't any more in the culture swap it out with another mini.

I'm going to record time to first maggot sighting, to first pupae sighting, and how long before the flies in the cup have increased in number approximately 50%. Obviously hydei take longer than melanos, which is why their data will be kept separate. I'm just looking for enough of an increase in flies to prove it works and could be used as a smaller burst of flies to a culture. My big cultures are in 2L bottles and produce thousands so I don't think putting that in a single hatch enclosure is really viable.

For a controlled test you need to keep the ff cups all at the same conditions, same viv temps, humidity and day/night cycle because its proven ff produce more in the dark. Also Hydei usually require a more nurtient rich media to produce well and they take almost twice as long. Also not much you can rely on without knowing the amount of males vs females as well as their ages going in the culture because if all are different you wont have evidence on which does better really. I'd start with making the media a bit more runny for sure to prevent it from drying out. Then I would look for a setup that will make it easy to put them in the nymph enclosures without crushing a hoard of nymphs its not easy when you have an entire hatch in a cage to heard around out of the way.
they're all being kept in the same conditions. They're standing next to each other on my shelf, same room, within a few feet of each other, no difference in height. They will be exposed to the same temperature and humidity as the others. As for knowing which is more successful based on males and females, I'm not so concerned about which one does better so much as if either of them work. if the shallow media cup flops and the deep media cup produces a horde then deep media is probably the better way to do this test. if they're both successful then I use less media in the shallow cup and can make more of them with the same amount of media.

 
We are not scientist, so our experiments will not compare with theirs, but our experiments satisfy us and I think for our purpose that is what matters most, not likely we are going to be in a magazine anyway!

 
We are not scientist, so our experiments will not compare with theirs, but our experiments satisfy us and I think for our purpose that is what matters most, not likely we are going to be in a magazine anyway!
Absolutely, why even try to advance the hobby through some real documented science....its not like most in the hobby are failing at culturing, breeding even simple husbandry we will continue to fall behind while the other side of the world advances on it all. But atleast we have names for our mantids and plan to teach them to eat noninsect diets while preparing to remove their heads for breeding....

 
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Absolutely, why even try to advance the hobby through some real documented science....its not like most in the hobby are failing at culturing, breeding even simple husbandry we will continue to fall behind while the other side of the world advances on it all. But atleast we have names for our mantids and plan to teach them to eat noninsect diets while preparing to remove their heads for breeding....
Okay, so my suggestion was a bit drastic. How 'bout if we just hold the female's 'claws' closed during breeding attempts? If she can't grab the guy, she can't eat him.

 
They breed in the wild without needing their 'claws' closed, but Ive seen and heard worse, even about duct taping the female down. The problem is most accept this as whats needed when in fact they are just impaitent or undereducated on the subject. And most of all why is it so important to go to these extremes? If they are not receptive why force it? Its not like your the hobby's last hope on keeping the bug here.

 
The alternative is taking care of your mantids so the female isn't hungry enough to be that interested in eating the male. I'd rather take care of my pets than torture them with manacles to stop the off chance she eats the male.
I read Rick's sticky entitled: My technique for mating mantids. He talks about the importance of keeping the female well fed prior to breeding attempts. However, he doesn't necessarily say that its a fail-safe solution.

"...............PROBLEMS OFTEN ENCOUNTERED:................4. You come in and check on the pair only to find your male being eaten or already half consumed. Just let them be. He can continute to mate and there is nothing you can do for him anyways..........."

 
I read Rick's sticky entitled: My technique for mating mantids. He talks about the importance of keeping the female well fed prior to breeding attempts. However, he doesn't necessarily say that its a fail-safe solution.

"...............PROBLEMS OFTEN ENCOUNTERED:................4. You come in and check on the pair only to find your male being eaten or already half consumed. Just let them be. He can continute to mate and there is nothing you can do for him anyways..........."
And its something that happens, the only way you'll be able to prevent it is by hurting the female, which can even lead to them being injured. People on here have tried it before and had their female stop eating afterward. Don't do it. Cannibalism happens, it happens everywhere, in the wild, in culture wherever. Just do everything you can to make the female uninterested and actually taking care of your bugs is a good start.

 
That's fine. Just tossing out ideas. Now I know its been unsuccessfully attempted. I'm happy to hear that cannibalism has been rare in your experience.

 
Best advice I got when I started this hobby not too long ago.... If you are gonna breed, you are gonna have looses. Expect it. No matter if it is mis molt or decapitation or whatever. I read somewhere and folks please correct me if its wrong that even in the wild it's only about 15 percent of males that loose their head after breeding. Ill try and find that link but that's pretty low considering I was always taught that they lose there head no matter what. Also, I've seen a few breeding videos and people that breed successfully always feed the female and some watch especially if the female is particularly mean but and I've read that some Arron standbys with chopsticks to intervene if the female goes for a grab but even with all of these precautions I've read that some people still loose their males. So it's a roll of the dice but holy cow there is no need to force anything. If it happens it happens. If it doesn't try getting a different female or sending your female in trade to someone else. All sorts of possibilities :) hope you have the info you were looking for keep us updated :)

 

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