A little electricity each day keeps the shark away.

Just offshore Cape Town, South Africa, researchers are busily setting up a new kind of shark barrier to keep the toothy predators from mingling with surfers and swimmers at popular beaches. Rather than the old standby of a shark net, this new barrier just punches sharks in the face. With electricity. Basically.

Why didn’t somebody think of this sooner?

Shark nets are somewhat effective in reducing shark numbers near swimming and surfing beaches. But that’s at least partially because they kill hundreds of sharks every year, in addition to whatever other hapless sea creatures get caught up in them. As helpful as traditional shark nets can be in terms of keeping ocean-goers safe, relatively speaking, they are environmental disasters.

Enter the electric shark puncher. The idea is to place big long cables on the sea floor, with strings of electrodes rising vertically toward the water’s surface. Sharks are abnormally sensitive to electric currents, especially at the pointy ends of their noses where jelly-filled pores called Ampullae of Lorenzini help them sense the electric fields of fish. When a shark swims into the electrode—bop—they get a little electric slap in the face. Enough to turn them right around. Most other fish don’t have the same sensitivity to electric currents sharks do, so they can brush up against the electrodes with no issues at all. Humans can reach out and grab hold of the electrodes if they want, with only a gentle electric tingle in response. No nets mean no harm to sharks or other marine life that typically get caught up in them and die.

“We’re doing our damndest to do something that’s environmentally friendly,” said Paul Von Blerk of the KwaZulu-Natal Shark Board. “The sharks are often in distresses and some die while caught in the nets. That is why we are looking for an alternative method.”

The electric barrier is still in testing phase, but the promise is there. The researchers only have to figure out how to keep the system operational in the pounding surf.