Chinese nymph care advice

[Mrwaylay]

Hey guys,
I had a chinese ooth hatch out last week, releasing about 200 nymphs. I housed these inside a large(ish) glass aquarium. As the lid was rather loose-fitting, I sealed up the aquarium using cling-film, and punched through numerous air-holes.
Then, I went to Amsterdam for the weekend...

Before I left, I added numerous pieces of damp kitchen towl to the enclosure, so the nymphs would have some moisture while I was away.

I got home last night, and roughly half have perished.
I think the lack of air-flow could be the cause of this, as the humidity in the tank was real high...

Any suggestions?
I have two more ooths waiting to hatch and I don't want the same to happen again!

I am thinking of using some real fine mesh instead of cling-film to seal the tank, as this will increase airflow right?

Thanks!

[matt020593]

You really need mesh on top of the cage for mantids, it gives them a great surface to grip onto and gives a lot more ventalation. Cling film is not suitable.
Usually most Chinese mantids that hatch will die in the first few weeks of life, due to the high morality rate with T. Sinensis.

[Mrwaylay]

Hey Matt, thanks for the reply.

I have started seperating the nymphs out in to individual containers; disposable plastic cups with ladies tights used for the lid! It's working perfectly.
There was a bit of cannibalism going on in the large tank, so I thought it was about time..

[hibiscusmile]

Yes, they die off for no reason, that is why God made so many in an ooth, the humidity won't hurt them, we hatch them here in Ohio and hmidity is our middle name :{

[Mrwaylay]

I'm losing more nymphs by the day!
I think I'm down to about 60 now..

What experiences have others have with hatching ooths of this species? Are losses like this quite normal, or is there something I'm not doing right?

All the nymphs are now in individual pots, with net lids, and a thin layer of vermiculite on the base.
I am not heating these containers at all, they are being kept at room temperature.
I am spraying the containers with water regularly (twice a day).

I know that this species experiences high mortality rates, but is losing numbers like this quite normal (200 -> 60)??.

I have two more ooths waiting to hatch still, and want to make sure I am keeping the nymphs correctly to acheive best results.

Thanks!

[muleyyy]

i hear that chinese mantis have a high mortality rate early on, there are a number of factors at work here

1/ nature (it just happens!)

2/ conditions - give them plenty of space, temperature is less important around 20 C is fine

3/ genetics if the ooth is a result of several generations of inbreeding it... i've been told that it will increase the likelyhood of bad sheds and the general mortality

bearing in mind that chinese mantis are quite common at the moment and you get so many young, i doubt anyone is trying to ensure they are genetically strong

[Mrwaylay]

Ah I see. So in-breeding could be a big factor hey. I shall keep that in mind.

So with nymphs of other species, the mortality rates aren't this high?
I am thinking of purchasing a ghost / Texas Unicorn ooth, but they are considerable more expensive than the Chinese. I don't want to splash the cash then have them all die on me so easily!

[muleyyy]

well this is what i was told at bugfest (an insect/invert show) by one of the guys from the PSG (phasmid study group) that the first and second generation of inbreds tend to be ok but after that you would occur increasing amounts of problems, i have no first hand evidence of this, and its quite difficult to track the generations of things like chinese mantis, but he did say that once you introduce new blood it can fix things a bit

i dont think its such a problem with other species as quite alot of them would have come from the wild anyway, or at least would only be 2nd gen, but then other species can be more challenging to rear (but at the same time more rewarding)

i know that with stick insect cultures its best to get new blood in when possible to counteract the inbreeding that occurs (obviously with species that have sexual reproduction!)

[Mrwaylay]

This may sound dumb, but when it come to hatching ooths, do you keep them in the same kind of conditions across the species, or do you have to vary temps. / humidity depending on which species the ooth is?

[muleyyy]

well i've never hatched an ooth myself (the idea of getting over a hundred baby mantids is a little overwhelming for me - maybe in the future...)

but i gather that the conditions should be the same for whatever the mantid you are keeping

from what i can see most mantis have similar conditions that they prefer with the exception of the more exotic flower mantis like the devils flower mantis or orchid mantis

[matt020593]

It depends on the species, I just hatched some Texicorns myslelf, about 28C is best to hatch them and keep them at. Ghosts should be incubated about 25-28C.
Chinese mortality rate is massive, most species have a much lower one. For instance I have about 50 Texicorns hatch(about a month ago) and about 7 have died so far.
I wouldn't buy anymore ootheca until your T.A.Sinensis ootheca have hatched as you will be overwelmed by two more lots of them LOL.

[WILDONES]

I Had The Same Problems With Mortality Rates. Turns Out You Can Stress Them Out! If There Is To Much Food In The Cage They Will Get Stressed And Wont Molt Properly Or On Time And End Up Dieing. I Had About 200 Nymphs And Lost About 1/2 Almost 3/4 But Never Had A Problem With Cannablism. I Kept Them All In A Aquarium All The Way Threw There Second Molting.