Sightings of giant water bugs reported

Common insect not commonly seen

Josh Pennell
Published on May 23, 2013

Next time you're enjoying a nighttime coffee in the parking lot of a Tim Hortons, keep an eye out for the giant water bug. If you spot one, you may think you've made some new and grand discovery.

Don't panic. This is education more than invasion or infestation. The truth is these insects are a natural part of our ecosystem, and they're actually quite common. But if you see one, you may have a rough time believing that.

MUN entomologist Tom Chapman says every year he gets people showing up at his door with giant water bugs, almost always in Tim Hortons coffee cups. It's not the franchise the bugs are drawn towards - it's the lure of the asphalt after dark.

The giant water bug lives up to its name and is the largest insect in the province, says Chapman. Also, as their name suggests, they actually live under water. When the pond they're in dries up, or when some take to wing to disperse, they do so at night. Sometimes those trips don't go quite as planned.

Chapman says the thinking goes that as these bugs fly over a blacktop parking lot on the hunt for a new, still pond to call home, they get a bit confused.

"You can imagine a parking lot with a set of street lights could look like a pond in the moonlight and starlight, especially when it's wet," says Chapman.

They've earned the nickname electric light bugs. The largely reflective surface looks inviting enough until they try and land. In theory, they should be able to take off again, but Chapman figures they get injured when landing on the asphalt. Then people pumping gas or having a nighttime coffee see either a dead or injured bug, usually like nothing they've ever seen in this province. Soon enough, Chapman gets a knock on his door.

"They always say they have something new to science," he says.

This year has been no different, though no live ones have been dropped off yet as happened last year. As an insect biologist, Chapman says he tries to keep that enthusiasm he sees in people when they do arrive at his door with their marvellous discovery while filling them in on the fact that what they have found is still marvellous, but also quite common.

Chapman says people usually think they're bringing him some type of beetle, but in the classification system of the natural world, giant water bugs are in the Order Hemiptera, and beetles are in the Order Coleoptera.

In other words, they're not the same thing.

A bug to be admired, not feared

The giant water bug certainly looks intimidating. Like all insects, it has three pairs of legs on the thorax - the part of an insect between the head and abdomen. The two front legs are modified for grasping, says Chapman. They sit under the water with their abdomen at the surface.

"In a pond it would sit in ambush," says Chapman, adding that a tadpole or stickleback would be possible targets.

A local vernacular for the bug is "toe nippers," though Chapman says that name might not be based on many actual incidents of people wading through a pond and feeling the wrath of the giant water bug.

"I've never met anyone who's been bitten by one."

Chapman did read an article one time in which somebody - all in the name of science, of course - held one by the back and stuck their finger near its mouth. The consequences were painful, according the article, he says.

The one thing Chapman knows for sure is that they don't make good roommates for each other.

"We had two live ones brought into the lab last year and we made the mistake of putting one in with the other and the one grabbed the other, stabbed it and then drained it of its fluids."

A student who had been keeping one of them - the victim in this case - was less than pleased, says Chapman; apparently a giant water bug has a face some people can love. It still might be best to not split the rent with one, though.

Globe trotters

Giant water bugs of varying species are actually found all over the world. If you Google them, you'll discover they often land on dinner plates in certain countries of the world, rather than just on ponds and parking lots as in this province. The species found in this province is called Lethocerus americanus. Anybody looking to keep tabs on the insect life of Newfoundland and Labrador can follow the Facebook group Insect Watchers of Newfoundland and Labrador, which was started by one of Dr. Tom Chapman's students.


* This article has been edited to correct an error in a biological term.