Death of Pregnant Mantids

[PeterF]

I have read some reports on the forums of seemingly healthy mantids dying more or less sudenly. Especially pregnant females. With little or no obvious reason.

I would like to offer a notion, with no experimentation to back it up.

Recently one of the grad students I am friendly with was telling me that over fed scorpions can become so fat that the spiricals become blocked (pinched I took it) and the scorpion dies. I haven't looked this up myself, but she is a sound resource, even though her actual thesis is about beetles and taxonomy (weeeeeeeeeeeeeee!). Nor do I know if this is an issue of complete blocking, or simply constriction and slow asphyxiation.

So, I have thought that fatty fat fat pregger mantids, over fed and bulging with ooth material and sundry could experience the same.

Not that there are not other explanations for some deaths. And not that over feeding isn't unhealthy in other respects. Simply that it was a thought worth considering.

 

[PhilinYuma]

Interesting idea, Peter. Certainly, as you know, the spiracles are one of the weak points in insect anatomy, are easily compromised and are the portals to a pretty inefficient respiratory system (one of the reasons, folks, why there will never be a mantis large enough to eat Chicago) It is certainly known that in hemimetabolous critters like the mantids, a bad molt can cause the pharate spiracles to detach incompletely from the shed skin, causing irreversible injury.

Also, a surplus of proteinaceous waste can't be just flushed out in urine as urea. If the nephridia are overloaded, not only does the formation of uric acid take up a lot of energy the surplus not turned into uric acid (I was thinking about this earlier) may escape into the hemolymph as lethal ammonia.

Personally, I'm in favor of any theory that inveighs against overfeeding. What seriously irritates me is that some folks overfeed their mantids just for the spectacle of watching them catch and eat living prey. "OMG, Mavis, look at him get that bigun! Look, he just munches bits off while it's still alive. Creepy, innit? Lets feed him another one!" Others believe that "food is love" and feed their "babies" in the same way that they feed themselves.

Am I ranting? I thought so, but I feel better, now.

P.S. Is the beetle student cute?

 

[hibiscusmile]

I agree with Phil and also I think your theory has a lot of merit to it. I also think that is why some become egg bound, Not sure why I think that, it's just that a lot are overfed prior to mating, and I think that hurts more than helps.

 

[Rick]

Not sure. I find wild mantids that are very very fat and they don't seem to have issues. I find that same condition in many captive mantids with no issues. I think it would need more research.

 

[dgerndt]

I'm still really new to mantids, but in my experience so far, my mantids will not eat if they're not hungry. I like to hand-feed my adult mio and she'll refuse food, and just climb all over it if she doesn't want it.

Your ideas on this subject sound very educated, though. I'll keep that in mind as I feed my mantids from now on.

 

[Krissim Klaw]

Since I am not into breeding and thus have never had any concerns with ooth sizes I have noticed that I have steadily downsized what I feed my adult females over the years. For me it was the difference in how much easier it is for the girls, especially as they get older, to move around and relax with a smaller abdomen. It isn't that they don't eventually end up rather fat too, but it is a slower and in my mind more natural process. The first females I had used to get large crickets and the like a day every day and though they did lay more and bigger ooths, there were times they just looked so ungainly trying to position themselves.