Cannibalistic or Communal?

For those out there that have had experience raising large numbers of nymphs together, which species have you found to have the lowest/highest rates of cannibalism?

More specifically, are new zealand nymphs cannibalistic? How long will they tolerate each other for?

Pretty much all mantids will eat each other. I do hatch ooths and keep the nymphs together until I am left with a number I can actually manage.

yeah, although cryptic spieces seem to be less cannibalistic tho.

The last batch of Tenodera nymphs I had started eating one another after the second or third molt. After that, it was guaranteed that they would feed off one another if not kept seperate.

Hope that helps.

The least cannibalistic species I've had were... Gongylus gongylodes (easy to obtain as of late), Didymocorypha lanceolata, Idolomorpha lateralis (stochastically extinct), and as of late Thesprotia graminis... which is a bit surprising, because they totally tolerate each other whilst being able to tackle pretty big prey (talk about a mantis thin as a needle grabbing a waxmoth too big even for Gongylus nymphs).

Cool. Thanks guys. I guess ill keep them together for the first month or so and hopefully by then ill have bought some new enclosures

Isn't P. paradoxa a relatively communal species?

As Kruszakus says, those species do well together, the ghost will also do well, but will eat each other if the occasion arises! And the new Zealand, will eat each other in a heartbeat.

All mantids are cannibalistic to a certain degree. I will give you some examples from the top and bottom of the list.

All Tenodera, Sphodromantis, Rhombodera, Iris, Mantis, Hierodula and relatives are rather cannibalistic and have to be housed individually after several molts. Further, Eremiaphila falls under this definition. You won't get them in Australia, but it's good to know...

Less cannibalistic are most Empusids (Idolomantis, Gongylus, Idolomorpha, Hypsicorypha), then Phyllocrania and most of the slender species (Euchomenella, Angela, Danuria, Thesprotia, Thesprotiella, Hoplocorypha), even Deroplatys can be housed together until subadult, if containers are large.

As a rule, the larger and structurated your enclosure is, the better you can keep mantids communally in it. You will always have some incidents of cannibalism, but if you use large numbers you will not care about the losses.

Of the Australian species, despite Mantis, Hierodula, Tenodera etc., Archimantis, Sphodropoda and relatives are rather aggressive. Less aggressive are the smaller ground- or trunk-living species (Paraoxypilus, Gyromantis, Ciulfina etc.), but they may be more difficult to raise. I don't have personal experiences with Orthodera, but I would keep them together in larger cages with living plants inside. This method works even with those species which are regarded by some people as too aggressive to be housed together. If you don't use large terraria, however, better keep them separately.

What happened with Hypsicorypha - I'm kinda hoping to breed this species one day. But was it a victim of the infamous "stochastic extinction"? Just like Idolomorpha? Cuz the 3rd generation was totaly infertile, and I'm kinda curious if that's what happened with Hypsicorypha gracilis...

No, I ceased to breed them when I got Idolomantis. I needed the cage. At that point almost noone had this species anymore, or did not succeed with the ones I sold, so it may be that they got problems. Mines were fine throughout all of the time. I offered a quiescence in winter and had two generations a year. Hypsicorypha weren't much appreciated at that time, as they lack lobes and are beige in color.

Kruszakus said:

What happened with Hypsicorypha - I'm kinda hoping to breed this species one day. But was it a victim of the infamous "stochastic extinction"? Just like Idolomorpha? Cuz the 3rd generation was totaly infertile, and I'm kinda curious if that's what happened with Hypsicorypha gracilis...

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What exactly is "stochastic extinction"? I've never heard the term before.

shorty said:

What exactly is "stochastic extinction"? I've never heard the term before.

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Bloody good question. It is not in either of my (dumb!) biological dictionaries and I get the feeling that several sources that use it on the internet don't know what it means either. If I get this wrong, anybody, please correct me.

Roughly, a "stochastic model" is a mathematical model based on probability. When you input data into such a model, one of a variety of outcomes may ensue. It is the opposite of a deterministic model where you can predict that a given input will produce a particular outcome. It crops up a lot in weather forecasting, which is why forecasts are often wrong :blink:

Stochastic extinction usually occurs when the population of a particular species is drastically (a very unquantifiable word) reduced. A good example of this occurs in the South American rain forest, where the habitat of a species is subdivided by logging and clearing into small areas each containing a population that may not be large enough to survive. Sometimes the population survives, sometimes not.

I imagine that Kruszakus (and correct me if I'm wrong, mate) is referring to the extinction of a cultivated species that is raised in captivity from a very small original breeding stock. The captive strain lacks "hybrid vigor" and is prone to extinction, but chance seems to play a part in whether the extinction event occurs or not. A famous example of a situation in which it did not occur is that of of the mutineers from The Bounty, who settled on Pitcairn Island in 1790.

Well, I know that I got that last bit right!

So, basically, there is a chance that a small breeding colony will become inbred and sterile after a couple of generations?

No.

What do all you guys have with all the inbreeding stuff?

I think I used the term in some mail. I put it in brackets to ensure it is not used in its normal context. Phil was only partially right. It refers to species which are bred by only one or a few breeders. If it not raised in numbers, it may be that due to multiple factors (most of which can be classified as breeder's fault, though) one particular breeder has only a few adults (and fail to pair them, e.g. because the male(s) is/are eaten) or only one gender left. If no exchange of specimens is possible, he will loose his stock. If this happens to all of the remaining breeders at one time, the species will vanish. This effect only occurs if captive populations are not large enough. One famous example which went this way is Ceratomantis saussurii. Hypsicorypha may be loosely put in this category as well, as there weren't many breeders who were interested in it at that time, and most did not succeed. Eventually, the species vanished when I ceased to breed it. However, as a North African species, there is some good chance that it will appear in stock again one day. I kept mines at 40-50° by day in summer, although they came from the Canaries.

This sucks - I find Hypsicorypha really interesting and I would love to give it a try one day. Dunno about you, but I like such stuff.

Well - I did not use that term as a refference to inbreeding, just as a way of portraying the situatio when a certain species disappears from the market and it's no longer kept be anyone in captivity.

Kruszakus said:

The least cannibalistic species I've had were... Gongylus gongylodes (easy to obtain as of late), Didymocorypha lanceolata, Idolomorpha lateralis (stochastically extinct), and as of late Thesprotia graminis... which is a bit surprising, because they totally tolerate each other whilst being able to tackle pretty big prey (talk about a mantis thin as a needle grabbing a waxmoth too big even for Gongylus nymphs).

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Watch out, Thesprotia graminis is in no way as communal as Gongylus.

yen_saw said:

Watch out, Thesprotia graminis is in no way as communal as Gongylus.

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I did not say they were.

So far they have been very tolerant - is their cannibalism more of a problem once females turn adult?

Kruszakus said:

The least cannibalistic species I've had were... Gongylus gongylodes (easy to obtain as of late), Didymocorypha lanceolata, Idolomorpha lateralis (stochastically extinct), and as of late Thesprotia graminis... which is a bit surprising, because they totally tolerate each other whilst being able to tackle pretty big prey (talk about a mantis thin as a needle grabbing a waxmoth too big even for Gongylus nymphs).

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Your post here does sound like you categorized them the same level..... I have kept all those species you mentioned above and they are not on the same level of cannibalism (No mantis is communal!)

As for T. graminis, cannibalism can occur through out all stages, not only when female mature into adult.