Giant water bug ~ Lethocerus americanus
Motionless, seemingly at rest above the shallow waters of a roadside ditch, the creature caught my eye — dark enough to be noticed; large enough to invite a closer look.
In time, I learned I’d found a giant water bug: the largest true bug in the United States. Nearly four inches in length with a flat, oval-shaped body, a short, pointed beak on the underside of its head, and overlapping wings at the end of its abdomen, the creature seemed entirely capable of living up to its nickname: the toe-biter.
Adapted to living in water, the giant water bug breathes through snorkel-like tubes located at the end of its abdomen. When extended to the surface of the water, the tubes collect air from the atmosphere, then add it to a bubble of air trapped beneath the insect’s wings. From that bubble, air enters its body through holes in its abdomen: one of the neatest bits of engineering in the insect world.
Using its flattened hind legs as oars, the water bug skulls over to a plant growing near the surface of a pond or stream and secures itself. After snatching an unfortunate victim with the hook-shaped claws of its forelegs, it pierces the prey with its beak, injecting powerful toxins which paralyze and liquify the victim — bones and all — for easy consumption.
Able to catch and consume creatures fifty times its size, the giant water bug’s menu is extensive; it feasts on aquatic insects, crustaceans, tadpoles, salamanders, fish, and frogs.
Especially active in late summer and early fall, giant water bugs begin moving from shallow water to deep, where they can continue to hunt during the cooler months and bury themselves in mud during cold spells. This season of movement is the time that they’re most likely to be seen by humans.
One of the more memorable passages from poet and naturalist Annie Dillard’s Pilgrim at Tinker Creek involves her own encounter with a giant water bug, and the frog that became its victim. The tale seems entirely suitable for Halloween, and far more haunting than a grimacing jack-o-lantern or bed-sheeted ghost.
A couple of summers ago I was walking along the edge of the island to see what I could see in the water, and mainly to scare frogs… As I walked along the grassy edge of the island, I got better and better at seeing frogs both in and out of the water. I learned to recognize the difference in texture of the light reflected from mud bank, water, grass, or frog.
Frogs were flying all around me. At the end of the island I noticed a small green frog. He was exactly half in and half out of the water, looking like a schematic diagram of an amphibian, and he didn’t jump.
He didn’t jump; I crept closer. At last I knelt on the island’s winter-killed grass, lost, dumbstruck, staring at the frog in the creek just four feet away. He was a very small frog with wide, dull eyes. And just as I looked at him, he slowly crumpled and began to sag. The spirit vanished from his eyes as if snuffed. His skin emptied and drooped; his very skull seemed to collapse and settle like a kicked tent. He was shrinking before my eyes like a deflating football.
I watched the taut, glistening skin on his shoulders ruck, and rumple, and fall. Soon, part of his skin, formless as a pricked balloon, lay in floating folds like bright scum on top of the water: it was a monstrous and terrifying thing. I gaped bewildered, appalled. An oval shadow hung in the water behind the drained frog; then the shadow glided away. The frog skin bag started to sink.
I had read about the giant water bug, but never seen one. “Giant water bug” is really the name of the creature, which is an enormous, heavy-bodied brown bug. It eats insects, tadpoles, fish, and frogs. Its grasping forelegs are mighty and hooked inward. It seizes a victim with these legs, hugs it tight, and paralyzes it with enzymes injected during a vicious bite.
That one bite is the only bite it ever takes. Through the puncture shoot the poisons that dissolve the victim’s muscles and bones and organs — all but the skin — and through it the giant water bug sucks out the victim’s body, reduced to a juice. This event is quite common in warm fresh water. The frog I saw was being sucked by a giant water bug.
Of course, many carnivorous animals devour their prey alive. The usual method seems to be to subdue the victim by downing or grasping it so it can’t flee, then eating it whole or in a series of bloody bites. Frogs eat everything whole, stuffing prey into their mouths with their thumbs. People have seen frogs with their jaws so full of live dragonflies they couldn’t close them. Ants don’t even have to catch their prey: in the spring they swarm over newly hatched, featherless birds in the nest and eat them tiny bite by bite.
That it’s rough out there and chancy is no surprise. Every living thing is a survivor on a kind of extended emergency bivouac. But at the same time we are also created. In the Koran, Allah asks, “The heaven and the earth and all in between, thinkest thou I made them in jest?”
It’s a good question. What do we think of the created universe, spanning an unthinkable void with an unthinkable profusion of forms? Or what do we think of nothingness, those sickening reaches of time in either direction? If the giant water bug was not made in jest, was it then made in earnest?
If we describe a world to compass these things, a world that is a long, brute game, then we bump against another mystery: the inrush of power and light.Unless all ages and races of men have been deluded by the same mass hypnotist, there seems to be such a thing as beauty, a grace wholly gratuitous.
About five years ago I saw a mockingbird make a straight vertical descent from the roof gutter of a four-story building. It was an act as careless and spontaneous as the curl of a stem or the kindling of a star.
The mockingbird took a single step into the air and dropped. His wings were still folded against his sides as though he were singing from a limb and not falling, accelerating thirty-two feet per second per second, through empty air. Just a breath before he would have been dashed to the ground, he unfurled his wings with exact, deliberate care, revealed the broad bars of white, spread his elegant, white-banded tail, and floated onto the grass.
I had just rounded a corner when his insouciant step caught my eye; there was no one else in sight. The fact of his free fall was like the old philosophical conundrum about the tree that falls in the forest. The answer must be, I think, that beauty and grace are performed whether or not we will or sense them. The least we can do is try to be there.
Lagniappe 
An impressive bug to be sure. Its lifestyle may inspire a little revulsion in humans, but that is hardly the criterion for judging other life forms is it?
It certainly isn’t. Adaptation is adaptation, and this creature’s way of being in the world is remarkably interesting. Granted, it comes by ‘toe-biter’ honestly, but the solution to that is to keep our toes away from it!
I don’t think I should like to come upon a giant water bug while taking my regular dip in the lake. It is impressive though, and so very large! A fellow’s gotta eat, I suppose. It’s a wonderful capture, Linda.
The more I look at him, the more I see a resemblance to Darth Vader. I think it’s that long body, that looks like a cape. I read Dillard’s story about her encounter with one years and years ago. When I realized I’d actually found one, I had to share it — and Halloween seemed the perfect time.
Certainly scary enough for me. Linda!
At least he won’t steal our Halloween candy — but keep an eye on the pets! Can’t you imagine a film with a bunch of giant water bugs as the villains? It could be the best thing since Attack of the Killer Tomatoes.
…I am not sure I would have the nerve to watch it!
“The least we can do is try to be there.” Also true about life.
Wisdom is wisdom, wherever it appears. That line always reminds me of Woody Allen’s similar assertion that “showing up is 80 percent of life.” The fact that there have been so many variations on the theme suggests that a lot of people recognize its truth.
I remember that passage from Pilgrim at Tinker Creek. It was the first thing I thought of when I saw your photo.
Finally seeing one of the creatures certainly brought the passage to life in a new way. Now I’m hoping to find the tree with the lights in it, and perhaps even a caddisfly larva.
As soon as I saw the photograph I thought: this hulking creature looks appropriate for Halloween. The description of its eating habits that followed confirmed the ghoulishness attributed to this day.
The words “bones and all” got me thinking that insects don’t really have bones. Later, the mention of fish and frogs in the list of the bug’s prey justified the bones.
Physics and math teachers will have to quibble with Annie Dillard’s “accelerating thirty-two feet per second.” That’s because “thirty-two feet per second” is a velocity. The acceleration she meant is “(thirty-two feet per second) per second.” In other words, at the end of each second, the bird’s velocity is thirty-two feet per second faster than it was at the beginning of that second. It takes two mentions of a time unit to designate an acceleration.
The physics and math teachers will need to quibble with me, not with Annie Dillard. When I found the line “accelerating thirty-two feet per second per second” in the original text, I wrongly assumed that it was a ‘thinko’ on the part of the person who transcribed it, and removed the ‘duplicate’ words. If you follow the link to the entire passage, it’s there, and correct, and I’ve changed the passage here accordingly. The next time I bump into something like that, non-scientist me will pursue it a little further.
I’ve been holding on to this photo for months, waiting for Halloween. Both the bug’s appearance and its behavior seemed perfectly suited for the occasion: not to mention being more interesting than blow-up lawn decorations.
The bug looked menacing in your photo, before I read your article, and learned of its dining habits. Darth Vader is good, I thought of Spartans, wearing all-business, grim armor of molded leather or bronze. A very scary customer, and an excellent choice for a Halloween tale.
I understand each creature out there has its niche and its role to play, but I would rather have a frog sitting next to me in a café, eating with its thumbs, then share a table with this bug, and it’s eating habits. A scary dude, thanks for the chills!!
There are insects that give me just a touch of the creeps (like millipedes) but this is the first one I’ve found that looked actually lethal — armored up and ready to inflict damage. Apparently it’s more common in the southeastern states, where people regularly encounter them when fishing or swimming.
Just tonight I learned that after a female giant water bug lays her eggs, the male takes over and guards them until they hatch. I suspect he does a pretty good job of it. Bother his kids, and risk dissolvement.
Particularly scary for a frog prince.
Isn’t that the truth? I was doing a little more reading about them, and learned that they’ll occasionally take on a snake, successfully. That would be something to see.
I know bugs serve a purpose, even when I can’t figure out what it is.
One article I found said they’re beneficial in the landscape because of the number of insects they consume. I thought it was interesting that, over in your part of the country, they’re also known as ‘electric light bugs’ because they like to congregate under street lights at night. As big as they are, they’d be pretty easy to pick out in a crowd!
Here’s a bit of information I just found on a Minnesota state site:
“Giant Water Bugs serve an important role as being the top invertebrate predator, especially in wetlands that don’t have fish to control insect populations. Much like lions, tigers and humans, Giant Water Bugs are at the top of their food chain and keep populations of smaller invertebrate from exploding and taking over.”
So now we know!
Ah-ha, so who keeps THEM in check?
I’m thinking. Perhaps no one keeps them in check. They could be massing on the edge of the marsh, plotting…
The last war to be fought on Earth will be them and roaches – to the bitter end!
Wonderful post, Linda. It’s a scary, beautiful world out there!
Thanks, Tina. I just learned today that the male of this species is the one who tends the babies, so it’s got a softer side, too. Going by appearances alone doesn’t always tell the whole story.
Yuck!! This creature’s bad enough to look at, without hearing how it sustains its life. Perhaps ‘vampire bug’ would have been a better name for it? Thanks, Linda — now I’m going to have to work extra-hard to get the image of this thing eating that poor frog out of my mind!
I hope the image has faded a little, Debbie. I’ll soon be back to flowers and birds, but when I found this really extraordinary creature, there was no question that he needed to be the star of the show on Halloween. What I’d really like to see is that frog Annie Dillard mentioned — the one with his mouth full of dragonflies. That would be a sight — like a chipmunk with its cheeks filled with seed. Of course, a chipmunk is much cuter.
I love my naturalist lesson. Thanks.
You’re welcome! There’s no end of things to learn about: the quirky, the odd, and the puzzling as well as the beautiful and pleasing.
The bug is fascinating, but at 4″, I’m not sure I’d want to get too close. Your photo is excellent and makes it all the more suitable for Halloween.
This was another time I was happy to have my telephoto lens. Even if I’d been willing to wade into the water, I was afraid that if I approached too closely, it would fly. I would have liked to have gotten a frontal view, too, but there just wasn’t any way to do that. No matter: the side view shows its legs and claws quite well.
Once again Linda, you’ve rendered me almost speechless.
Such a fascinating creature and I love the except with it.
You have great restraint in waiting till now to show it off!
Of course you would be the one to notice my restraint; that made me smile. More often than not, a photo like this turns me into a five-year-old, running into the house with my latest discovery and eager to share. That may be why I often think of blogging as show-and-tell for grownups.
This critter is fascinating, for any number of reasons. It certainly is one of those that raises the question: why in the world did this get added to the world’s inventory of oddities? Of course, from the giant water bug’s perspective, it’s not odd at all — just extremely well-suited to the world in which it lives.
I’ve seen some large bugs but this one, which I have not, is a giant among them. It’s feeding habits are similar to several others that I have seen, the most familiar being the ambush bug which inserts it’s proboscis into a captured prey, dissolving and slurping those luscious innards.
Your sharing of Dillard’s writing reminded me of a frog I once saw while camping in the Adirondacks many years ago. As I gazed into the frog’s eyes I was surprised to see no movement or seeming care of my closeness. Then I noticed the snake’s jaws engulfing it’s back half.
That is a nice image and look at those feet. They appear as though they could latch on to a human. You mentioned Darth Vader above. That’s science fiction…did you watch it?
No, I didn’t see the film. In fact, even thought I had a vivid mental image of Darth Vader, I couldn’t remember his name or which films involved his character. Of course a search helped me out. ‘Science fiction villain’ puts Mr. Vader right at the top of the list.
“Eat or be eaten” seems to be the rule, and that poor frog you encountered certainly had moved to the less pleasant side of the equation. I assume the snake was pretty happy. The closest I’ve come to having a bit of my own body dissolved away involved a bite from a brown recluse spider. Had I not gone to a storefront clinic operated by an Indian doctor who was familiar with the symptoms, I might have had some real problems. The good news is that the giant water bug can be annoying to humans, but not lethal.
I love those feet. It’s easy to see how the flattened ones at the back could serve as oars. I wonder what its top speed is? I found this tidbit on a Minnesota site: “Giant Water Bugs serve an important role as being the top invertebrate predator, especially in wetlands that don’t have fish to control insect populations. Much like lions, tigers and humans, Giant Water Bugs are at the top of their food chain and keep populations of smaller invertebrate from exploding and taking over.”
Lions, tigers and humans…shouldn’t that be bears? If we leave things alone nature does a pretty good job of keeping things in balance. The Giant Water Bug being exhibit number one.
Yes, indeed. A bite from a brown recluse would be trouble and then some. Store front clinics have become not only popular but important gap fillers when a hospital is not an option or too far when speed is of the essence. Had I waited for my PCP to be available instead of going to one I might not be writing this now.
Yes, Mr. Vader has earned his place in history. Let’s hope he stays as fiction.
And we’re glad you’re here, believe me. There are three areas where I trust and act on my judgment at least as much as I do the experts: my health, the weather, and when to evacuate for a hurricane.
I’d guess the time to evacuate depends a lot on experience and reading the winds for yourself. But the forecasters, while not perfect on most weather, seem to zero in on hurricanes as closely as possible given their wont to wander. I appreciated your checking on me and encouragement during my illness, Linda. Getting your emails was a boost on down days.
After reading this I am glad that the Giant Water Bugs aren’t any bigger than they actually are.
Believe me, you’re not alone. I had enough trouble getting used to the so-called palmetto bugs when I moved to Houston. I don’t care how many people tell me they aren’t roaches; to me, they’re giant, flying roaches, and despicable. I might even be more tolerant of the giant water bug than a palmetto bug.
I’m glad we don’t have Giant Water Bugs in the UK! (And even gladder that they aren’t any bigger – yikes!) I have lots of lovely frogs in my garden and I wouldn’t like them to be ‘bugged’.
As the old saying goes, everyone has to eat, but the dining habits of some of nature’s creatures can be a little off-putting for us humans. The poor frogs must be as tasty to their predators as they are to some people here. I knew that birds and snakes dine on them regularly, but it certainly startled me to discover that an insect could eat one, too.
Goodness, what a terrifying creature. Thank goodness it’s only four inches long! xxx
I think most of us agree — four inches is quite long enough. It is a fascinating creature, though, and I was quite surprised to learn just how many insects and other creatures have developed ways to drink their dinners!
I like the close-up and how you filled the frame. I had no idea they preyed on fish also and other large creatures.
It’s amazing, isn’t it. The toxicity of what they inject into their prey must be substantial; it would have to subdue the larger prey pretty quickly to prevent the prey from getting away, or doing damage to the water bug. While I bought my 70-300mm lens for birds, that’s what I used here, and it worked wonderfully well. There was no way I could have gotten close to the insect otherwise.
That’s what I love about telephotos. I don’t know that I can forgive Canon, however, for changing the lens mount of their full frame mirrorless line.