AUSTRALIA -- Sharks in western Australia are using Twitter to warn swimmers when they are close.
Scientists have tagged more than 320 sharks, including great whites.
When a tagged shark swims within a kilometer of popular beaches, it triggers an alert to a computer.
The computer turns the shark's signal into a tweet. It gives the size and breed of the shark, along with an approximate location.
The project allows beachgoers to make informed decisions about going into the water.