The Common Water Strider is a water bug that looks a lot like a big mosquito walking on the surface of the water. Its body can grow just over 1/2 inch long and is dark brown or black. Like all insects, it has six legs. The front pair of legs is short, and the middle and back legs are very long. Water striders live on the surface of ponds, slow streams, marshes, and other quiet waters. Common Water Striders eat living and dead insects on the surface of the water. Some are aquatic (water) insects, such as mosquito larvae coming up from the bottom, and others are terrestrial (land) insects, such as butterflies or beetles that accidentally land on the surface.
Injured dragonflies are a favorite food, as are worms that fall in the water. Water striders have a sharp mouthpart, called a rostrum, to suck up body juices from prey. Common Water Striders have very good vision and move quickly on the water. The short front legs of a water strider are for grabbing prey. The middle legs push the insect forward, and the hind legs steer. The shape of their legs and their light weight keep them from breaking through the surface.
In breeding season, water striders communicate by sending ripples to each other on the surface of the water. Females lay eggs at the water's edge, usually on plant stems. When eggs hatch, nymphs (baby striders) must grow for over a month before they become adult water striders. Water Striders must always keep moving to so they don't become prey themselves to fish or other predators. These insects do not have wings. They are usually in large groups and prefer the protection of overhanging trees and shade. Common Water Striders can live for many months, and adults can overwinter. They can crawl inside a plant stem when it gets too cold.