Australian yabbies have the same ‘sixth’ sense as sharks – the ability to listen to electrical signals that alert them to prey or predators, according to new University of Melbourne research.

Study team researcher Mr Blair Patullo (Zoology) says that, like the great white shark (“one of the biggest predators on the planet”), yabbies use electroreception to hunt prey.

Electroreception is the ability to detect tiny electrical signals in water.

“We have provided the first evidence that yabbies ‘listen’ to electrical fields for their survival,” he reports.

“All animals make small electrical signals when they swim. To detect them is a powerful ability because it enables animals to ‘hear’ predators and prey, before they are seen or even smelt.

“It makes sense that yabbies would also listen to these signals, but despite much evidence in vertebrate species, until now there was no evidence in the simpler invertebrate animals,” he says.

Mr Patullo says that listening to electrical signals could help the yabby detect a nearby tadpole to capture a meal; detect a predatory fish for a fast getaway; and detect a fellow yabby for companionship.

The study was conducted by playing electrical signals through electrodes placed in the water near a yabby in total darkness. Darkness was maintained to ensure that the only sensory cue changing in the tank was the electrical field. The researchers observed how yabbies responded when they heard the signals.

The research, led by Professor David Macmillan and a team of dedicated students, was published in the February 2007 issue of the prestigious international journal Current Biology.

Mr Patullo says the research not only reveals more information about the survival techniques of yabbies, it has further application in the management and preservation of animal species.

“As with many new discoveries we have raised more questions than we started with and some of those relate to the management, fishing and culture of yabbies, other crustaceans, and the species they interact with.

“We know of electrical fields used to enhance fishing or to prevent species dispersing. This new finding could be valuable in developing new techniques in farming and preserving animal species.”