In 2005, Eric Stroud, the managing partner of Shark Defense, a New Jersey company that specializes in shark-repelling technologies, happened to be carrying a rare-earth magnet as he passed a tank full of sharks. The sharks fled, and Stroud took note. After further tests, Stroud and his colleagues found that sharks that came within 20 inches of rare-earth magnets similar to the one he had been carrying would consistently swim away.
The discovery earned Shark Defense $25,000 from the World Wildlife Fund’s annual International Smart Gear Competition, which rewards inventors who develop new methods to keep animals from getting tangled in commercial fishing lines. Shark Defense is now investigating ways to embed the metals in nets. And Stroud says the same metals, worn as an anklet, could act as a personal shark deterrent.
Adapted from Juliet Eilperin's book, Demon Fish: Travels through the Hidden World of Sharks.
Five amazing, clean technologies that will set us free, in this month's energy-focused issue. Also: how to build a better bomb detector, the robotic toys that are raising your children, a human catapult, the world's smallest arcade, and much more.