Praying Mantids

There’s no need to fear these alien looking creatures… unless you’re a butterfly or wasp.

September 12, 2024 | Don Scallen | Notes from the Wild

Praying mantids could serve admirably as inspiration for malevolent aliens in sci-fi movies. Their sharply spined forearms, tucked against their sleek bodies in their eponymous praying positions, would portend appropriate menace. Their triangular heads pivoting on slender necks, bulging with large, penetrating eyes, unnervingly responsive to the slightest movement, would make movie-goers squirm with discomfort.

Two introduced species occur in Ontario. The European mantid (Mantis religiosa) is the most widespread and the species most likely to be found in Headwaters meadows. Though impressive, this mantid is eclipsed in awesomeness by the Chinese mantid (Tenodera sinensis) which can grow to 10 cm, or 4 inches, long. iNaturalist, an online registry of flora and faunal diversity, doesn’t yet record any Chinese mantids in Headwaters, but they have become abundant just to the
south of us in Oakville, Burlington and Toronto.

praying mantids ontario — The European mantid, which has a white spot on its underarm, can be spotted in the Headwaters region. Photography by Don Scallen.

Chinese mantid ontario — The Chinese mantid can grow up to four inches long, and have been seen in the Greater Toronto Area.

As introduced insects, mantids are often condemned as “invasive” – bad ecological actors that disturb ecosystems by preying on native species. But railing against them is akin to railing against the rising of the tides. They are here to stay. Better to accept their presence, observe closely and marvel at their magnificence.

And, though common, mantids are well dispersed on the landscape, likely because of territoriality. Their diet includes other predators like wasps and spiders, serving perhaps to balance the predatory pressures they exert on an ecosystem.

Chinese mantid eating butterfly — A Chinese mantid, green phase, snaring a monarch butterfly.

Mantids are ambush predators. Green and brown colouration allows them to hide in foliage, often near flowerheads that beckon flies, bees and butterflies. Though generally slow moving, their arms lash out in the blink of an eye to snare prey. Even large hornets are powerless in the arms of a mantid, futilely stabbing their stingers into thin air as the mantids eat them.

Despite their suitability as inspiration for malevolent sci-fi characters, praying mantids pose no threat to us – unless some tweak in the universe causes them to grow exponentially.

Then look out!