The first thing you notice about water striders is their rapid skipping across the water surface. Most insects of a water strider’s weight would quickly sink and drown. How do they stay on the surface? Recent research provides the answer. Water strider legs are covered in thousands of microscopic hairs scored with tiny groves. As reported in National Geographic, “These groves trap air, increasing water resistance of the water’s striders legs and overall buoyancy of the insect.” The water skipper’s legs are so buoyant they can support fifteen times the insect’s weight without sinking. Even in a rainstorm, or in waves, the strider stays afloat. If a water strider’s legs go underwater, it’s very difficult for them to push to the surface. Their legs are more buoyant than even ducks’ feathers. Unfortunately for the water strider, these extraordinary capabilities don’t extend to land. Their legs are almost useless on hard surfaces.
They are particularly effective predators of mosquito larvae. “Since mosquito larvae breathe through a snorkel that they poke through the surface of the water, the water striders can grab them by the snorkel and eat them. It’s always good to have some striders around. However, if there are too many water striders around and they run out of mosquito larvae, they eat each other.
Water striders are one of the most interesting and enjoyable aquatic creatures to observe. Best of all, they’re found widely across the Northern Hemisphere – in lakes, creeks, urban ponds, water features and even mud puddles. Their lives on the water’s surface make them easy for even a young child to observe. There have been some 1,700 species of water striders identified. While they superficially resemble spiders, they’re actually insects, members of the family Gerridae.