Testing the force of a shark's bite

The 2.4 metre long Great White shark was stored at the NSW Department of Primary Industries’ Cronulla Fisheries Research Centre of Excellence until researchers were ready to analyse its jaw and facial muscles this week.

A collaborative project involving NSW DPI, the Universities of NSW, Newcastle and Tampa, Florida, and led by Dr Stephen Wroe aims to reveal the cranial mechanics, bite force and feeding behaviour in the Great White Shark using high resolution 3-D computer simulations.

This week Dr Wroe and his team are dissecting the five year old shark and measuring the structure of its jaw and the muscles used in biting.

Underwater experiments with live sharks fail to adequately indicate the force of the Great White’s bite, and the sharks have been known to bite through materials that require much greater force than that so far observed in situ.

According to NSW DPI shark scientist, Denis Reid, sharks generally test bite before applying a full-force bite.

“The test bite has much less force”, he said.

The approach being taken in this project involves determining the maximum forces that Great Whites can exert using advanced mathematical and computing methods that were originally developed for the calculation of stresses in structures such as bridges.

The collaborating investigator in the project for NSW DPI, Dr Michael Lowry, said one of the project aims is to identify the shark species responsible for damage to submarine cables and towed arrays.

“Measurement of bite forces will help in testing and developing materials suitable for cabling and sensory equipment used in the marine environment.”

US shark biologist Dan Huber is working with the Australian team to learn whether sharks such as the Great White are responsible for damaging submarine cables and communication systems on US Navy submarines.

Dr Huber’s team has experimented with protective materials including Kevlar fibres as a means of protecting cables and arrays from attacks from marine life. See http://luna.cas.usf.edu/~motta/fishbite.html

Dr Wroe, from the University of NSW, is an expert on carnivore evolution who has helped pioneer new techniques that reveal the feeding habits of flesh-eating animals such as the Sabre-toothed tiger, African lion, marsupial lion and Tasmanian tiger.

NSW DPI contact: Dr Michael Lowry, (02) 9527 8407, michael.lowry@dpi.nsw.gov.au