Cat's eyes save lives

A nautical version of 'cat’s eyes' developed by defence scientists to mark and find underwater locations could also be used to locate oil fields or transatlantic cables, and help to avoid dolphins and whales being caught up in fishing nets.

Scientists from the Defence Science and Technology Laboratory (Dstl) have successfully shown in sea trials that the new underwater cat’s eye can reflect back a tuned signal, revealing its location, to existing sonar systems (for example, those mounted on maritime vessels).

Whales and dolphins also use sonar to navigate, so if the cat’s eye was attached to fishing net, they would be able to pick up the signal and avoid the area.

To date, battery-powered sonar location devices have been used by oil and cable companies that continually pulse a signal back to a sonar system. The new cat’s eye, however, is a passive system, meaning that it only sends a signal when sonar tries to identify it.