Big Bug
The giant water bug can hunt small fish and deliver a mighty bite.
By Bill Rhodes
If you live fairly close to a freshwater pond or lake and leave your porch lights on at night, you might be startled to hear a loud, heavy “thud” resonating off your door or wall on a summer evening. If you are brave enough to go out into the dark to find the source of the noise, you may see that the culprit is an enormous, flattened, dark-brown bug with formidable, pincher-like front claws, lying on the ground or holding on to the wall.
This fascinating creature is a giant water bug, Lethocerus americanus. It's attracted to lights, just like the multitude of moths buzzing and circling around your porch. And, as its name implies, it is a giant among buggy beasts. Measuring more than 3 inches from top to bottom, and an inch and a half across, it is one of the largest insects in North America and one of the world's largest aquatic insects. On your porch, it is truly out of its element. Moments before crash-landing, it was likely swimming, diving or walking along the edge of the nearby pond.
The “bug” in the name is significant. While many people use the term “bug” for all insects, spiders and other arthropods (invertebrates with jointed bodies and exoskeletons), scientists reserve the term “bug” for insects in the order Hemiptera. These are insects with sharp, needle-like mouthparts that they use to penetrate their food source — usually plants. Some bugs can be quite serious pests of our crops and gardens, but others use their stylet-like mouthparts to pierce other insects, injecting a chemical that paralyzes their victim and breaks down their insides. The liquified meal is then sucked up through the straw-like proboscis.
The giant water bug goes one step further. It is large and voracious enough to hunt not only other insects, but minnows, tadpoles, small frogs and even turtles and snakes. Pretty much anything swimming by can be caught by the bugs' powerful front legs and impaled by their needlelike mouthparts to become dinner.
Because insects don't breathe the same way we do — they have small openings called spiracles spread across their bodies that connect to a network of branching air tubes called tracheae — water bugs can remain submerged underwater for extended periods by carrying their own air supply. They trap air bubbles on their bodies that they can use to breathe, akin to a bug-sized scuba system. This bug is a snorkeler, too. While they wait for prey in the water, giant water bugs have an appendage on the tip of the abdomen that they can extend above water to collect oxygen.
If you are among the brave few who don't mind picking up a giant bug, just be careful. While the giant water bug eats prey smaller than you, it doesn't want to be eaten itself. It will instinctively try to pierce your finger or hand in an attempt to escape, and while it won't turn you into mush, the bite can be painful. Best to marvel at this king of bugs and let it be. It will almost certainly have flown off to return to its pond by morning.
Common name:
Giant water bug
Scientific name:
Lethocerus americanus
Habitat:
Giant water bugs live in freshwater ponds, marshes and streams in the U.S. and Canada.
Diet:
Insects, tadpoles, small fish, frogs and other aquatic creatures.
Did you know?:
Giant water bug fathers are very involved in child care! Females lay eggs by water and males guard them until they hatch.
