Backswimmers: Living Life Belly-up
by Vanessa Ting
It takes a lot of skill to photograph a backswimmer (family: Notonectidae) before it swims away from you, using its long hind legs as oars. Mostly found in ponds, freshwater pools and slow flowing streams, it can stay underwater for up to six hours, using air trapped in abdominal pockets.
Stealth is this bug’s main weapon, as it feeds on insects much larger in size, and sometimes even tadpoles and small fish. The backswimmer usually hangs on to submerged plants, releasing only when it spots its prey. Drifting up under it, it grasps the hapless victim with its front and middle legs, and bites and sucks out the body fluids with its sharp, tubular beak. It won’t hesitate to bite humans as well—be prepared for a sting!
For the male, this beak also serves as violin with the front legs as bow to make sounds that attract the female. The eggs can be inserted into or glued on to the surface of aquatic plants.
This particular genus, Enithares sp., normally remains at the water surface. When disturbed, it may dive 10-20cm below the surface, maintaining its position by rapid strokes of the hind legs. It can also swim horizontally while staying on the surface, or dive and anchor itself to a submerged object.
Read more about backswimmers here!
Photograph taken in the Institute of Biological Sciences (ISB) by Prof. Emeritus Dr Yong Hoi Sen of the Institute of Biological Sciences, UM.
Want to get up close and personal with backswimmers? Join water quality monitoring activities with UMCares’ Water Warriors! Don’t forget to email us all your wildlife photographs.
