Let Sleeping Sharks Lie

We divers like to think we do no harm when we descend upon a resting shark, but these guys need their sleep and we may be disrupting it.

So says Mateus Baronio, a scientist at Southern Cross University in Australia, who has spent five years studying grey nurse and leopard sharks around in Byron Bay with a state-of-the-art remotely operated vehicle (ROV). The $50,000 machine enabled Baronio to quietly get within inches of the fish and observe their breathing habits as they slept.

Unlike most sharks, grey nurse and leopard sharks are able to hover in the same position while resting. But because they sleep during the day, if too many divers converge on their position, they will stir and move away. "As soon as the divers leave the area, the sharks go back to sleep." Baronio told the Northern Star newspaper. "... if you have too many divers doing the wrong thing, you're going to have an impact on the sharks."