Local mantis population question

[bugboymark]

I live in NE Illinois.  Wondering if anyone else had noticed what I've observed this year.  In the neighborhood, there has ALWAYS been a pretty robust population of Chinese mantises. Over the last 3-5 years, it seems like there has even been a "bumper crop" of Chinese mantises.  Maybe the mild winters have helped?  Not sure, but last year I could walk to a co-op garden and field near my house and see countless mantises.  By early September, it wouldn't be unusual for me to count as many as two to three dozen or more adult mantises...many mating.  Seriously, it was like a mantis paradise! This winter, I saw ooths everywhere. I had at least a dozen that I over-wintered at home.  (from a handful of females I'd raised/mated)  Per usual, I distributed many of them to people I knew with gardens/lots of flowers, or decent landscaping cover early this spring.

The question part of this long-winded story....  Only one of 14 or 15 ooths hatched this spring.  I also had 8 Carolina mantis ooths I was planning on hatching/releasing (technically one of the few actual native species)....and none of those hatched either!  I figured I'd done something wrong during the winter diapause. Not enough humidity maybe?  I actually kept them in my refrigerator during the handful of really cold spells.  I misted occasionally.  But only ONE hatched!  It's been a boring summer not being able to walk around the yard and spot a mantis or two!  And even worse, I've made 4 or 5 trips to the local field near my house over the last couple weeks to walk through grasses, flowers, etc.  I can't even find a single mantis.  It's like they've all disappeared.  In past summers, I start to see adults at this time of year.  And we had an early spring/summer, plenty of humidity and heat, decent rains off and on all winter.  ??   Maybe just bad luck in my area, but I was wondering if anyone else (in IL, IN, S. WI, IA) that enjoys collecting wild mantis specimens has noticed the same thing or not.  I hope it's just me...

 

[ausar318]

Out where I live, in rural Indiana, it seems like there are more than usual, but only of the Chinese mantids. We don’t have any Carolinas where we live, because the Chinese out compete them, and literally eat just about everything in our field. 

Every time this year that I have went out and admired God’s amazing world, and found myself in our field, there have been dozens and dozens of them. You can’t take a single step without disturbing two or three of them. Especially the males, because they fly quite readily when disturbed. It’s rather fun to run through the forest and watch them all fly away. 

Bow that I think about it, though, this was the first year that we didn’t bale hay from our field. I would assume that that definitely increases the population in my area. I will say this, though, the population can go up and down quite easily. A few years back, when I was still just a young laddie of 15, my parents decided to get chickens. The chickens, of course, were free ranged, so they ate literally every insect that moved. They consumed just about all the mantids, as far as I could tell. I would go all around our property, and I’d be lucky if I found a single mantis.

That is when I decided to step in, and save the world! (Only to the mantids). So I spent the next couple weeks searching endlessly for all the mantids I could find, and I was only able to get four, two males, and two females. I was a noob, and I didn’t know there were actually people who kept these insects, so I though I was doing something amazing. I had enough brains to know when the little buggers were adults, as I was able to successfully breed both pairs. Unfortunately, I thought the females only laid one ootheca, so once I got one from each of the females, I started to neglect them, and they died soon after. I popped the egg sacs in the fridge, and took them out the next spring. One of them hatched over 350!!! (I literally counted them ?, and it took FOREVER!) the other one only hatched out three or four. I released them all, but kept 3 of them. They are the ancestors to the ones that I raise now, three generations later. As far as the ones in the wild, I was able to spread them out enough that the chickens (more like demons ?) wouldn’t eat them all. 

I guess the moral of my long story is this: the population will fluctuate, and as long as there are no unnatural, external influences, such as someone harvesting many of them, the population will bounce back. If they have always been there, then it is safe to assume, for the most part, that they will always be there. Like I said, though, if someone is harvesting a bunch of them, that will probably eventually cause a drastic population drop. 

 

[Rick]

I would say a lack of Chinese mantids is a good thing. 

 

[Synapze]

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[bugboymark]

Rick - I understand that sentiment. Outside of female giant African mantises (from nymph to adult), I'd be hard pressed to find a more aggressive/voracious eating species. (though I've raised a lot fewer species than most people on this forum!) In this area, T. sinensis has all but eliminated all other competition. However, I'm not sure there are any natives (European or Carolina) in the area to fill the void. If the deficit continues into the fall, I might try to purchase/plant as many European ooths out there as possible.  They seem to prefer similar cover.  Lots of tall grasses and flowering plants (goldenrod, milkweed, thistles, etc.) Maybe they'll take hold and establish a population again. Could be a good experiment.

I have to admit that the Chinese mantises were the ones that got me started on the hobby.  I've raised plenty, so I have a soft spot in my heart for them.  Just can't believe they are nowhere to be found this year...

 

[Synapze]

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[River Dane]

Carolinas are native, and Europeans tend to be less aggressive and smaller, and so as not as much a threat to native species, as opposed to the Chinese mantises.

For us, I don’t think there’s any particular benefit for using these alternative mantids, as we have the Stagmomantis in culture and Chinese mantises are supposedly more effective at eliminating pests. But it helps nature and native species.

 

[Rick]

Rick - I understand that sentiment. Outside of female giant African mantises (from nymph to adult), I'd be hard pressed to find a more aggressive/voracious eating species. (though I've raised a lot fewer species than most people on this forum!) In this area, T. sinensis has all but eliminated all other competition. However, I'm not sure there are any natives (European or Carolina) in the area to fill the void. If the deficit continues into the fall, I might try to purchase/plant as many European ooths out there as possible.  They seem to prefer similar cover.  Lots of tall grasses and flowering plants (goldenrod, milkweed, thistles, etc.) Maybe they'll take hold and establish a population again. Could be a good experiment.

I have to admit that the Chinese mantises were the ones that got me started on the hobby.  I've raised plenty, so I have a soft spot in my heart for them.  Just can't believe they are nowhere to be found this year...

I would have the same sentiment about the European mantids. They, along with the Chinese are not native to the US.