It was really starting to bug me (pun intended!) that I was finding good quantities of the eggcases of the Carolina Mantis, but I was not finding the adult insects. I gradually convinced myself that this was simply because the behavior of this species was different to that of the introduced Chinese Mantis. The latter spends most of its time stalking prey around flowering plants. The former, I reasoned, must spend its time stalking insects in leafy, shrub environments and this would account for its usually browner and more speckled appearance, designed to blend in better with woody branches rather than with green leaves.
Things came to a head when Pat Sutton recently (and very kindly) encouraged people to read my blog post about mantises and to consider the message that it contained - that we should be removing the non-native, destructive species from our landscapes. Prior to this, CMBO associate naturalist, Kathy Horn, had mentioned to me that she had photographed a mantis last summer, in the process of laying one of those long, thin eggcases - clearly the native species that I had not been able to find I thought. When Kathy sent me the photos however, a cold shiver ran down my spine; here, very clearly, was a large Tenodera species - an Asian mantis, and it was indeed laying one of those elongated eggcases. A scramble through as many references as possible revealed the horrible truth - we have a third, invasive mantis species in Cape May County.
So, I write this note here because, firstly, I am always keen to admit to my mistakes and have the record set straight and, secondly, I want anyone who may have saved, printed or otherwise downloaded my original mantis post to delete it and go back to the post again as I have corrected the error (you can use the link in the first paragraph above to go straight to it).
Do we have a mantis problem? Yes we do! As an example, here's a batch of 254 Tenodera eggcases, removed from a field in Erma by my wife and me recently - perhaps a quarter of what was actually there. Bear in mind that 50-100 mantis nymphs might emerge from any one of these - you do the maths!! [Photo by Mike Crewe]
Please, please, please, do not release non-native, potentially highly invasive insects into your garden. If you garden in an environmentally friendly way, nature's own native predators will arrive and deal with any outbreaks of pests you might have, provided you garden thoughtfully. If you plant a monoculture, you will get a pest problem that you might need to deal with. Plant a balanced garden with a good mixture of plants, and very little is likely to become dominant and overwhelming - at the very worst you will get a few holes in some of your leaves. Do bear in mind that these introduced mantises prey mostly on essential plant pollinators - they are in your garden eating bees, butterflies, beetles and other beneficial insects. They do not know the difference between what you might consider a pest and an insect that is beneficial to your garden. How would they?