Damsels in distress wise up to survival in the big ocean

By David Chen and Nathalie Fernbach

You've got to develop some clever tricks if you're the small, tasty fish in a big ocean.

We may not credit fish with much intelligence, but scientists have discovered that baby damsel fish are outsmarting predators by pitting them against each other.

Scientists at the Centre of Excellence for Coral Reef Studies in Townsville have found that baby damsel fish emit chemical distress calls when captured, in order to create chaos and a possible escape.

"What happens is they release special cues from their skin in miniscule quantities that attract lots of other predators," James Cook University Professor Mark McCormack said.

He said the new arrivals try to steal the captured fish from the original predator and in the melee, the damsel can often sneak away.

"They are racing around after the predator that has grabbed the baby fish and in doing so, the other predator gets scared and releases the prey," Professor McCormack said.

"What we have found, is that by attracting another predator to the site, it actually increases its likelihood of survival by 10 to 15 per cent."

Professor McCormack said the finding gives them an insight into just how sophisticated fish are.

"Many of us treat fishes as really quite dumb little creatures; you know. the whole three-second memory," he said.

"And what we have found over the last few years is they have an incredibly sophiosticated mechanism of learning and an incredibly sophisticated way of actually interacting together."

The research also found that habitat degradation dramatically influences the ability of fish to respond to their environment and to learn.

"As coral reefs degrade, it seems as though those chemical cues that are released no longer function," Professor McCormack said.