Yes, fish do have ears
Jaws drop when Kerryn Parkinson tells people she studies fish ear bones for a living. Her parents are amused by her work and her children's friends often give her a stern look and say, "Fish don't have ears".
But fish do indeed have ears – inner ear organs that are sensitive to how deep and how fast they're swimming. And in a scientific twist, Parkinson, a research officer with UTS, can determine the life history of a fish, from hatchling to adult, by studying tiny bones embedded in those internal navigational aids.
"They're smaller than a grain of sand," Ms Parkinson says of the ear bones, or otoliths. "We slice them, polish the slices and look at them with an environmental scanning electron microscope. It gives us an image like tree rings."
This enables her to determine the age and rate of growth of seadragons. That's of huge importance in conservation, she says.
"We must make sure we understand the important facts of their life history so we can plan the best way to manage them, the best conservation strategy."
Ms Parkinson hastens to add that no seadragons are harmed in the name of science. As part of the UTS collaboration with the Abyss Scuba Diving club in Ramsgate, divers will collect any dead seadragons they come across, from which Ms Parkinson will remove the otoliths. The fish, prized for their beauty, will be returned to the collectors.
As her friends and family can attest, being a dab hand with an otolith is an unlikely skill. Ms Parkinson got into otoliths, literally, as part of her Masters research on pipefish. Along with seahorses and seadragons, the snaky-looking creature is a member of the Syngnathidae family.
Working first with UTS marine ecologist David Booth and then scientists in the UTS Microstructural Analysis Unit, she refined otolith analysis techniques to enable her to study the 3- to 17-centimetre-long pipefish.
In so doing Ms Parkinson has extended the use of the technique significantly, earning her the nickname Queen of the Otoliths. "When David calls me that I refute him," she says, humbly. "It's daunting."
Provided by University of Technology, Sydney
