Bug Index

 Assassin Bug

Bigeyed Bug





Giant Diving Beetle

Giant Stoneflies

Giant Water Bug

Ground Beetles

Honey Bee


Ladybird Beetle



Pirate Bugs

Praying Mantid

Predatory Mites

Rove Beetles


Syphid Fly

Tachnid Fly

Yellow Jacket



The Giant Water Bug is one of the largest insects in the U.S. and Canada. Giant water bugs are approximately 1.5 inches (3.8 cm) in length. Some species grow as long as 4 inches (10 cm). Because it often turns up under street lights and porch lights, it is also one of the most asked about insects. It is commonly mistaken for a beetle or even a cockroach. Alternate names include toe biter because they can deliver a nasty bite, and electric light bug because they are attracted to lights.

Clear, freshwater streams and ponds, preferring those with aquatic vegetation.
Giant Water Bugs like slowly moving water, especially where there is emergent vegetation such as cattails. They usually grab hold of a plant near the surface, and stick their short breathing tube out of the water to allow them to breath while waiting for prey. With their powerful front legs they are able to grab other bugs and prey as big as small fish, frogs and salamanders. They pierce their prey with their sharp beak and secrete enzymes that dissolve the body tissues, thus allowing them to suck up the resulting liquid.

Life Span
One year or longer

Larvae eat small aquatic invertebrates, while adults prey on any small animal they can handle, including insects and other aquatic invertebrates. They also hunt vertebrates such as tadpoles, salamanders and small fish. Grasping and holding prey with their powerful forelegs, giant water bugs thrust their sucking mouthparts into their prey. Many Giant Water Bugs are kept in zoos, where they are fed crickets

Ambush Hunters
Giant water bugs are ambush hunters, lying motionless and waiting for their prey. Predators of giant water bugs include birds, fish and other aquatic predators. When sitting motionless, giant water bugs resemble dead leaves. This allows them to hide from both potential prey and possible predators. However, their best defense is to escape and hide when alarmed.

Adult giant water bugs capture larger prey species by using their clawed front feet and chemicals which are injected into the body of the prey. The enzymes turn the prey’s insides into liquid, which the giant water bug can suck up.

Identifying Characteristics
The Giant Water Bug has piercing, sucking mouth parts, and a short, pointed beak on the underside of the head. The other distinguishing characteristic is the fact that the wings overlap at the hind end of the abdomen, forming an X like pattern. Other than that, the sheer size of the insect and the unusual shape of the front legs help identify it.

The Giant Water Bug is found throughout the northern United States and Canada,  wherever there is standing or gently running water. Giant Water Bugs are active all year, but are most commonly seen in the late summer and early fall. At this time of year the adults are leaving the shallow ponds at night to look for deeper bodies of water where they can remain active throughout the winter under the ice. They are often attracted to lights such as porch lights, where people find them the following morning.

Although not really dangerous, the Giant Water Bug can give one a nasty bite. One person described the bite as very painful, causing the finger and whole hand to swell up dramatically, to the point where they lost all use of the hand,and remaining thus for about two weeks. If you are going to handle this insect, it should be done with care.