How to Tell If a Water Bug Is a Male or Female?

Identifying the Sex of Water Bugs

• 1

  Find a body of water where known water bugs exist. Fill your glass jar or container with some of the water from the pond or stream where you will be doing your research. Use your visual reference or guidebook to identify the insects. Use your aquarium fish net to collect a few of the water bugs that reside near the water's edge and carefully transfer them into your container.

• 2

  Use your magnifying glass to more closely observe the physical characteristics of the water bug. While most types of water bugs lay their eggs under the water's surface or in clusters on nearby plants until the larvae hatch, in the case of giant water bugs the female will attach the eggs to the back of the male and he will carry them until the larvae emerge.

• 3

  Look through the bottom of your glass container and make a close observation of the insect's abdomen. Water bugs partake in a mating routine that is often referred to as traumatic insemination. Due the female's lack of an exterior sexual organ the male must slash a hole in the female's abdominal wall with his large forelegs and releases sperm into the cavity. Female water bugs that have previously mated will show scarring on the abdomen and you can actually tell how many times a female has mated by counting the number of visible scars.

• 4

  Observe other characteristics such as behavior to distinguish the sex of water bugs. Because in most species of water bugs the male undertakes the courtship rituals during mating, certain behaviors like chirping and scent emission. In some species the females will assist though, echoing the loud male chirping with a weaker response. Other male mating behaviors include the displaying of their legs or antennae.