LEUVEN , Belgium, July 16 (UPI) -- Scientists in Belgium say they've figured out how water fleas, unable to survive outside water, disperse eggs among ponds -- they hitchhike.

Frank Van de Meutter and colleagues of the Catholic University of Leuven in Belgium said pond-dwelling insects call backswimmers provide the Daphnia water fleas' eggs with a ride as they flit among ponds, New Scientist reported Wednesday.

Researchers put backswimmers in a bucket of water with 1,000 eggs then allowed them to take flight, caught them and examined them for the presence of eggs.

Of 45 backswimmers caught, researchers found 30 had eggs attached. Researchers found the insects' hairy abdomens allowed eggs to attach, explaining how the Daphnia catch a ride from pond to pond.

"Even after the backswimmers were rather roughly caught with a bucket, Daphnia eggs remained attached to the body, especially on the hairy keel at the underside of the abdomen and on the haired parts of the legs," says Van de Meutter.