Australian shark experts have enlisted the help of great whites and tigers to find out whether four “bite-resistant” materials can provide a measure of protection against their bites – and report that wetsuits made from them should now be added to the ‘toolkit’ of measures available.
While shark bites on humans are rare and, when they occur, usually investigative or accidental rather than predatory, they can still result in external and internal injuries in the form of lacerations, punctures, crushing, tissue and blood loss.
The researchers from Flinders University’s Southern Shark Ecology Group (SSEG) in South Australia say that while authorities often rely on controversial blanket protection for certain areas, such as shark-nets, interest in personal deterrents is increasing, though their efficacy had not been scientifically tested until now.
The study tested four lightweight puncture-resistant wetsuit fabrics – Aqua Armour, Shark Stop, ActionTX-S and Brewster – which incorporate materials such as Kevlar or the ultra-high molecular weight polyethylene used in sailing rope.
Great whites and tiger sharks were chosen because the two species are reckoned to be those responsible for the most unprovoked bites and (with bull sharks) among the top three with the highest rate of fatal bites.
Superficial to critical
The Flinders scientists were joined by experts from New South Wales’ Department of Primary Industries & Regional Development, which helped to fund the project, and assessed the materials across four categories of severity – superficial, slight, substantial and critical – comparing the damage sustained to that on standard 3mm neoprene.
“While there were small differences between the four tested materials, they all reduced the amount of substantial and critical damage, which would typically be associated with severe haemorrhaging and tissue or limb-loss,” said Dr Tom Clarke.
“Our study showed that bite-resistant materials incorporated into wetsuits can reduce damage from large white and tiger sharks (up to 3m) compared to standard neoprene wetsuits, even from moderate and severe bites.”
“While these suits don’t eliminate all the risk – for example, internal injuries may still occur – our results indicate that they can reduce blood loss and trauma from major lacerations and punctures, potentially saving lives,” concluded SSEG leader Prof Charlie Huveneers.
“Our findings will allow for informed decisions to be made about the use of bite-resistant wetsuit materials for occupational activities, as well as enabling the public to make appropriate decisions about the suitability of using these products.”
The results of the survey have just been published in the journal Wildlife Research.
