Snapping Shrimp And Feeding Sea Urchins Make Noisy Guides
Research that shows fish and crabs swim towards the source of underwater sound, potentially offering a technique for
re-stocking depleted reefs, has won scientist Dr Craig Radford a prize in the MacDiarmid Young Scientists of the Year
Awards.
Using an underwater listening device, Dr Radford identified snapping shrimps and feeding sea urchins as making the
loudest sounds beneath the ocean. His study also showed underwater ambient noise around New Zealand’s coast gets louder
twice a day with the sound of shrimp rapidly closing their claws and sea urchins scraping their teeth on rocks while
feeding being major contributors to increased noise levels at both dawn and dusk.
Craig, who is based at the University of Auckland’s Leigh marine laboratory, is runner-up in the Understanding Planet
Earth category of the MacDiarmid Awards, which are presented by the Foundation for Research, Science and Technology with
Fisher & Paykel Appliances as principal sponsor.
Fish and crab larvae are frequently dispersed tens of kilometres out to sea and Craig set out to investigate how they
get back to the coast. He found that reef fish and crab species swim towards underwater sound, concluding that noise
generated around the coast plays an important role in guiding baby fish and crustaceans to a suitable habitat in which
they can settle.
Craig says replicating underwater sounds could be a means of attracting fish back to depleted reefs and helping fish and
crabs to flourish in reefs which have been slow to colonise.
He is currently completing a post doctoral fellowship with the University of Auckland, continuing research into how
larval fish and crabs use underwater sound as an orientation cue. This includes trying to determine the frequencies they
are listening to, how loud underwater sound needs to be for them to hear it and how far offshore they can pick up sound.
Craig attended Melville High School in Hamilton, completed his undergraduate degree at the University of Waikato, his
Masters at the University of Canterbury and his PhD at the University of Auckland.
He is collaborating on his research into underwater sound with scientific teams in Australia and the United Kingdom and
was invited to present his findings at the 8th Larval Biology Symposium in Portugal in July of this year.
ENDS