PERTH, Australia - Dolphins in one western Australian population have been observed holding a large conch shell in their beaks and using it to shake a fish into their mouths - and the behavior may be spreading.

Researchers from Murdoch University in Perth were not quite sure what they were seeing when they first photographed the activity, in 2007, in which dolphins would shake conch shells at the surface of the ocean.

"It's a fleeting glimpse - you look at it and think, that's kind of weird," said Simon Allen, a researcher at the university's Cetacean Research Unit.