Why Water Striders Make Terrible Lifeguards

With the drought officially over and the summer heat upon us, people all across California are heading outdoors. For many, that means a day on the river or relaxing by the lake. The wet winter means there’s plenty of habitat for one of nature’s most curious creatures. Water striders, also called pond skaters, seem to defy gravity. You’ve probably seen them flittering across the water’s surface, dodging ripples as they patrol streams and quiet backwater eddies.

Scientists like David Hu at Georgia Institute of Technology study how water striders move and how they make their living as predators lurking on the water’s surface. It’s an amazing combination of biology and physics best understood by looking up close. Very close.

This Is Why Water Striders Make Terrible Lifeguards
Water striders create circular waves when they move. The waves announce the water strider’s presences to their peers. (Josh Cassidy/KQED)

Water striders are insects with six legs. They use the front and back legs to hold themselves up and the middle pair to row. “They’re basically like little rowboats,” said Hu. But unlike the oars of a rowboat, water striders’ legs don’t penetrate the surface of the water. Water striders use their center pair of legs to push against dimples […]

Summary
Title
Why Water Striders Make Terrible Lifeguards
Description

Water striders, AKA pond skaters, seem to defy gravity: flitting across water's surface, dodging ripples as they patrol streams and quiet backwater eddies.