Shock and flaw: Dr Charlie Huveneers on shark repellents and other research

blindboy
Talking Heads

As well as being a keen surfer, Dr Charlie Huveneers is one of Australia’s leading researchers working on sharks and rays. He is an Associate Professor at Flinders University, Research Leader of the Southern Shark Ecology Group, and Co-director of the Centre for Animal Behaviour. His latest research was into the effectiveness of a variety of shark repellents.

Swellnet: So what's your background in surfing?
Dr Charlie Huveneers: I started surfing when I moved to Australia about fifteen years ago and have had the opportunity to surf in many locations around the world including South Africa, Indonesia, France, England, Brazil, Nicaragua, USA, Australia, New Zealand, French Polynesia, and Palau. 

Is that what led to your interest in sharks?
I got interested in sharks at around twelve-years-old when I did a presentation about sharks for school. The book I read to do my presentation emphasised how little we knew about sharks, which sparked my interest. We now know a lot more about sharks and there is a large number of students, junior and senior researchers working on sharks worldwide.

However, there is still a lot we don't know. For example, while we increasingly know where sharks are going, the factors driving some of the small and large-scale movements are less understood - and are more complex than 'where food is'.

Out of the 500-plus sharks species, there are also many about which we barely know anything and new species are regularly being discovered or described.   

What is your academic background?  How do you get to be a shark researcher?
Following an undergraduate degree at the University of Southampton in England, I did a PhD on wobbegong sharks in NSW at Macquarie University. I moved to South Australia in 2009, for a joint position between the South Australia Research and Development Institute [SARDI] and Flinders University. I'm now working full-time at Flinders University with the College of Science and Engineering where I teach Marine Biology and Animal Behaviour and lead a research group focused on the ecology and biology of sharks and rays. 



Are there many researchers working in this area in Australia? Globally..?
While there were not many people focusing on sharks and rays when I first started, scientific interest in sharks has been continuously increasing and there is now a growing number of scientists and students working on sharks in Australia and around the world.

Can you briefly explain the research you have done on shark repellents? And the results..?
I've worked on three major studies testing the efficacy of personal shark deterrents. Across those studies, we tested seven products in a range of situations including breaching, which involves sharks rising out of the water in pursuit of a prey. This ensured that testing occurred when white sharks were in a predatory mode. We also tested deterrents using bait ensuring a certain level of motivation.

Our studies show that white sharks can be deterred by some shark deterrents, including in situations when sharks are attempting to feed on a natural prey. One of the devices tested also affected and effectively stopped the breaching behaviour of white sharks. However, none of the devices tested provided a guaranteed protection with white sharks.

For example, the Freedom+ Surf reduced the percentage of times the shark obtained the bait from 96% to 40%. It also kept white sharks further away on average - although sharks were still capable of being within close proximity. The other shark repellents, however, had little or no measurable effect on white shark behaviour.

Of course, testing is required in different locations, for different shark species, and in different circumstances, before the universal effectiveness of any proclaimed shark deterrent can be quantified completely. Nonetheless, our study identified one product that reduced the likelihood of an interaction with white sharks by more than 50% - and identified others that did not.

Given the results for the Freedom+ surf, can you explain how it works?
Sharks, rays, and skates are capable of sensing weak electromagnetic fields detected by ampullae of Lorenzini in the head of sharks and in the head and pectoral fins of skates and rays. Although electro-reception detection threshold of sharks and rays is species-specific, studies have shown that sharks and rays can show a behavioural response at levels as low as <1nV/cm. This led to the concept of using electrical fields to create repellents to reduce the probability of an attack.

Electric shark deterrents therefore aim to overwhelm the electro-sensory organs of sharks by applying a strong localised electric field. Some people have suggested that sharks might be attracted to electric repellents from a distance prior to being deterred. However, electric fields dissipate quickly in saltwater, hence why sharks were still able to come in close proximity to the deterrents, and sharks use other senses to detect preys from a distance - for example, olfaction and hearing - not electro-reception.

We also previously tested whether sharks were attracted to electric deterrents prior to being deterred and found no detectable attraction effect.

What other research on sharks have you done?
My research group works on a broad range of topics related to sharks and rays including assessments of their vulnerability to fishing pressure and other human, environmental, and climatic impacts, and investigations of their movement dynamics and residency patterns. Recently, a lot of my research has focused on the effects of wildlife tourism, shark bite mitigation measures, and public perception of sharks. 

Why is shark conservation important?
Broadly, sharks and rays are more vulnerable than most other vertebrates, with one in four shark and ray species being threatened with extinction, mainly as a result of overfishing. However, this is the overall conservation status of sharks and rays, and some populations are stable and have been commercially fished sustainably for decades, while the extinction status of some species is improving.

Other species are considered critically endangered and many regions in the world have documented sharp declines in shark populations. 

Is there any evidence for an increase in the population of white sharks around the Australian coast?
Although many people will say that they've never seen so many sharks when surfing and that the number of shark bites in recent years has to be related to an increase in the number of sharks, there is no scientific evidence that the number of white sharks in Australia has increased - or that it is increasing.

However, there is also no evidence that the Australian white shark population is currently decreasing or stable. There is unfortunately no robust scientific data available on white shark population trends.

This lack of empirical information is due to the challenges of accurately estimating the number of individuals in a population that undertake large-scale migrations. A recent genetic study has estimated the Australian population size of white sharks, but could not reliably determined whether it was going up or down. One modelling study has, however, suggested that under zero fishing mortality - that is: no white sharks are caught through bycatch or in the beach meshing program - the annual increase in population abundance likely varies between 2 and 6% per year.

Several studies are also underway to hopefully shed more light on whether white shark numbers are increasing.

Comments

atticus's picture
atticus's picture
atticus commented Monday, 10 Dec 2018 at 1:25pm

The number of times I've read that electronic repellants attract sharks is only outnumbered by the times it's been explained to be impossible, yet it's a furphy that never goes away.

freeride76's picture
freeride76's picture
freeride76 commented Monday, 10 Dec 2018 at 1:43pm

There maybe be no robust scientific data about large scale population trends for white sharks but we are now getting robust empirical data from the smart drumlines and other tagging programs that there are at least seasonal and regionally abundant populations in some areas.
Most notably the north coast of NSW.

Wonder if Charlie is reading whether he has any workable hypotheses to account for this?

lost's picture
lost's picture
lost commented Monday, 10 Dec 2018 at 1:59pm

I wish he had called out the devices that simply do not work. These are the magnet based products - yet these are still sold everyday of the week promising protection but giving none. They are a scam plain and simple yet the surf industry turns a blind eye. I've been vocal in this topic on their social pages but was quickly banned.

knB

rooftop's picture
rooftop's picture
rooftop commented Monday, 10 Dec 2018 at 2:48pm

So refreshing to see some science on this topic.

Wonder if this thread will turn into the usual mess...

"Kill them all!"
"Save them all!"
"Sharks are evil bastards!"
"Sharks are majestic guardians of the sea."
"Flake and chips please."

OHV500's picture
OHV500's picture
OHV500 commented Monday, 10 Dec 2018 at 3:58pm

HeHe totally - lets stick to facts - maybe :)

haggis's picture
haggis's picture
haggis commented Monday, 10 Dec 2018 at 4:53pm

I used to own a shark shield (the surfboard one) - it was easy to attach and set up and it looked like a clever bit of kit. I bought one after I was in the water at the same time as there was a shark attack at the next beach up. I used it once. I found that you got electrical pulses when the tail touched your leg. I found it could also wrap around your leg like a leash. I sold it on gumtree within the next week. I have never seen anyone having them on the back of their boards where I surf. However, that is what I found, others may think they're great.

Anyone else owned one?

There are a lot of urban myths about the shark shield. The best one I've heard, and there may be absolutely zero truth in it, was that the locals at Cactus send blokes in to the beach who come out and surf with the shark shields on, as they (and many others) believe that it brings sharks in. I see that Charlie mentioned it in the above article "Some people have suggested that sharks might be attracted to electric repellents from a distance prior to being deterred"

blindboy's picture
blindboy's picture
blindboy commented Monday, 10 Dec 2018 at 6:06pm

haggis, I had that concern when I first heard of the concept but am satisfied with the evidence now. You might have missed this
"We also previously tested whether sharks were attracted to electric deterrents prior to being deterred and found no detectable attraction effect."

monk's picture
monk's picture
monk commented Monday, 10 Dec 2018 at 6:18pm

I have one and use it most times I surf (south west WA). Haggis I think you are thinking about a different model. The Freedom+Surf goes into the kick-pad and has a stick-on antenna which sticks to the underside of the board and attaches to the tailpad. I don't notice any difference in board weight but I do get constantly electrocuted when duck-diving or taking off - when two hands are on the board and pushed slightly underwater (like a muscle-twitch) and it is quite a bit stronger when I accidentally touch the metal antenna on the board's underside. That being said I don't mind that too much (it means it is working I guess) and it gives me a bit of piece of mind. I bought it when this study was released (and the WA govt provided rebates). Now that I have one I notice the antennas on the underside of other surfers boards, and I see them all the time in the Margs region, quite a lot of crew have them around here. They are a bit of a pain to take out and recharge (and put back in) when you just want to surf, but it is potentially a small price to pay for not being eaten alive. @lost you can see all of the devices tested that did not appear to work in the scientific paper (google it) - the wax and magnets were never going to work, but I reckon they could surely tweak the Rpela and have that working up to speed with the Sharkshield

johnruciak's picture
johnruciak's picture
johnruciak commented Tuesday, 11 Dec 2018 at 11:15am

"constantly electrocuted" ..you can only get electrocuted once monk :)

monk's picture
monk's picture
monk commented Tuesday, 11 Dec 2018 at 12:22pm

"constantly" = every 2mins or so. For the entire session. This is pretty constant in my books!

epictard's picture
epictard's picture
epictard commented Tuesday, 11 Dec 2018 at 6:28pm

I think John's [inaccurate] pedantic definition of electrocute involves dying, hence 'you can only do it once. Which would be effectively true if that was the hard definition. In saying that, and keeping to the theme of pedantry, it does involve at least being severely injured. So electrocuted may not be the exact correct word, that is unless you are receiving severe burns on your legs every time you surf.

Apart from that it is obvious what was meant.

johnruciak's picture
johnruciak's picture
johnruciak commented Tuesday, 11 Dec 2018 at 6:34pm

yeah, sorry, bored at work

monk's picture
monk's picture
monk commented Wednesday, 12 Dec 2018 at 1:47pm

Ha, I guess "zapped" is the official term. It would be shocking if these devices really electrocuted people.

Coaster's picture
Coaster's picture
Coaster commented Monday, 10 Dec 2018 at 9:35pm

Interesting article, blindboy. Here’s another reasearcher you might put on the list to interview in the future.
https://lighthouse.mq.edu.au/article/bright-idea-lights-under-boards-may...

blindboy's picture
blindboy's picture
blindboy commented Tuesday, 11 Dec 2018 at 8:42am

It's an interesting idea but obviously needs a lot more work.

Tunafish's picture
Tunafish's picture
Tunafish commented Monday, 10 Dec 2018 at 10:48pm

Good read. I like the even handed response to the last question. Some would only say the first part which is deliberately misleading. I do think a scientist using his credentials to promote one product at the expense of all others needs to make a declaration of financial interest. I'm sure this was an oversight, but I like to see it, otherwise I just assume that he has "skin in the game".

stunet's picture
stunet's picture
stunet commented Tuesday, 11 Dec 2018 at 6:26am

No oversight, Tunafish, the paper was published in August 2018 and came out with this statement attached:

"This project was funded by the New South Wales Department of Primary Industries Shark Management Strategy (SMS) Competitive Annual Grants Program, Government of South Australia, Ocean Guardian Pty Ltd, and the Neiser Foundation. We openly and transparently declare that Ocean Guardian contributed financially to the study, but that Ocean Guardian was not involved in the study design or implementation, nor did they have access to the data post-collection. Nor did Ocean Guardian provide input into data analysis, interpretation, writing of the manuscript, or the conclusions drawn. The study design followed a protocol developed for a previous study (Huveneers et al. 2013b), which was not funded by Ocean Guardian. In summary, Ocean Guardian had no opportunity to influence any aspect of the study or its conclusions, apart from providing some financial support to realise the field project (e.g., boat hire, equipment purchase, etc.) in the same manner as the other funding agencies. The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript."

You can read the whole thing here: https://peerj.com/articles/5554/

simba's picture
simba's picture
simba commented Tuesday, 11 Dec 2018 at 6:57am

Well gotta say that the testing was a bit flawed in some aspects especially when you consider that Chillax wax was designed to put off a shark by its smell but if you do the trial by using gallons of tuna oil and burley hows that ever going to be a fair test?Also in the real world no one surfs in those conditions.

simba

stunet's picture
stunet's picture
stunet commented Tuesday, 11 Dec 2018 at 8:04am

My understanding is Chillax purports to mask the smell of surfers - i.e humans - so would chumming the water with tuna oil matter?

Also, the chum was used to attract sharks and the same method was used across all devices so there was no advantage or otherwise.

simba's picture
simba's picture
simba commented Tuesday, 11 Dec 2018 at 8:22am

Well the tuna oil would override the smell of the chillax wax and to say that the wax wouldn't have some effect in normal surfing conditions is still un proven cause no one will surf in a tuna oil slick....ever smelt tuna oil well it stinks.I know they have to attract the sharks some how just dont believe this was a fair test.

simba

jbshack's picture
jbshack's picture
jbshack commented Tuesday, 8 Jan 2019 at 3:59pm

Thats a very excellent evaluation. Testing so many products back to back is flawed heavily IMHO. Its kinda like testing effectiveness of 5 brands of beer. You drink two cans of the first brand and nothing all good, then two cans of the second brand, no problems for some, two from the third brand and your starting to get pissed, the final two cans from the last two brands puts you over the edge, So is it now fair to conclude that the last three brands have a higher % of getting you pissed than the first two brands? As the above statement was made, The NSW government paid $50000 grand to test 4 products, $12500 each. Then a fifth company paid $50000 to have theirs included? really in what field would that not be considered a conflict of interest.

blindboy's picture
blindboy's picture
blindboy commented Tuesday, 8 Jan 2019 at 9:44pm

I think your comparison is pretty weak jb and the suggestion that the money contributed by the company influenced the results verges on the libellous. Stu posted the disclaimer regarding funding above. If you have evidence that this is not true you need to produce it. Making unsubstantiated allegations of scientific fraud is serious stuff. Put up or ....... well you know the rest,

Tunafish's picture
Tunafish's picture
Tunafish commented Tuesday, 11 Dec 2018 at 10:49am

Thanks Stu

rooftop's picture
rooftop's picture
rooftop commented Monday, 10 Dec 2018 at 11:07pm

I agree about the last question. It's good to know that we don't know enough about the population levels.

Regarding financial interest, if his study results favour one product over another then as a scientist his only duty is to report that, regardless of which company it happens to benefit.

If he has no financial interest in the company then there's no conflict and he has nothing to declare. Do you know whether he has any "skin in the game"?

Tunafish's picture
Tunafish's picture
Tunafish commented Tuesday, 11 Dec 2018 at 11:24am

Hi Rooftop. No criticism, just "critical appraisal". I would guess that most people promoting products on my smart phone are giving a paid endorsement, regardless of their academic credentials. I would rather know if a plug is coming from a shareholder in the company. That is why disclosure of financial interest is required in research publications. In this instance, it appears as if the manufacturer did pay (in part) for Dr Huveneer's work, but they have done what they can to reduce the chance of bias. Realistically, it is difficult to find funding from objective sources and he has produced useful work in a field which effects us all. Good on him

rooftop's picture
rooftop's picture
rooftop commented Tuesday, 11 Dec 2018 at 12:53pm

Yeah, we're on the same page here. Posted my comment before Stu's reply above re: funding.

Optimist's picture
Optimist's picture
Optimist commented Tuesday, 11 Dec 2018 at 1:46am

I surf in a remote area and am alone in the sea 90% of the time. I find the Jesus shield works best for me. A quick prayer to The boss before paddling out ,that he would protect me and let me enjoy what He has made, gives me peace of mind and a heightened awareness of my surroundings. Hope you all have a very happy Christ mas.

MidWestMonger's picture
MidWestMonger's picture
MidWestMonger commented Tuesday, 11 Dec 2018 at 7:52am

I found praying to Huey or king neptune more effective. Jesus apparently has little time for surfers. Heard he got rolled badly first time out due to inability to get underwater duckdivivg

wallpaper's picture
wallpaper's picture
wallpaper commented Tuesday, 11 Dec 2018 at 9:31am

I think he meant Bruce Springsteen...or maybe that bloke who runs the newspapers

sin nombre's picture
sin nombre's picture
sin nombre commented Tuesday, 11 Dec 2018 at 4:57pm

Don't you remember he doesn't do underwater duckdiving because he can walk on water.

MidWestMonger's picture
MidWestMonger's picture
MidWestMonger commented Tuesday, 11 Dec 2018 at 10:11pm

Yes that's right Sin Nombre. That's why he bounced to shore like a riderless log at the pass instead of pulling his famous pose in the barrel like he claimed he would in the car park.
Anyway enough fake news, back to science

waxyfeet's picture
waxyfeet's picture
waxyfeet commented Tuesday, 11 Dec 2018 at 1:39pm

Jesus isn't real, praying does't do anything other than talking to yourself. Stop believing in superstition.

ps: I spent nearly 10 minutes to get through the bloody 'I'm not a robot, click on a traffic light' thing just to post the above, so you better listen and stop the rubbish!

GOBS1979's picture
GOBS1979's picture
GOBS1979 commented Tuesday, 11 Dec 2018 at 11:13am

Nearly fell off my chair !!! HaaaHaaaHaaa Midwest Monger you get the award for the best retort of the year mate!!!

FrazP's picture
FrazP's picture
FrazP commented Tuesday, 11 Dec 2018 at 5:44pm

I use a Rplea. Find it really easy to use and I can't notice any effect on the board performance. You can get a good kick if you put your hand in the wrong spot at the wrong time but that is pretty easy to avoid. You'd have to think a shark would really hate it.

Surf a bit on my own in deep water and it eases the mind a bit.

The bloke that runs it seems like a really good guy. His latest testing research is interesting and shows it is close to the Shark Shield performance levels in Huveneers report. Huveneers report panned the Rplea a bit (actually all the others from memory). I think Rpela's test was done in a bit more of a realistic way without whipping the sharks into a full on chum frenzy and they have tweeked the design a bit.

As for the magnetic bands and stuff, went fishing at Albany Island and the bloke running it was telling us he bought one for protection but they actually attract/fire up the reefies around there. Didn't think that could be right but i saw it for myself - they will actually attack it without being baited to it and it did nothing from a prevention side. I would have thought they would at least work a bit, and the shark bandz video can't be fake - which makes it all difficult to reconcile.

I guess if a Whitey really wants you nothing you could run on a surfboard would be 100% effective.

SurferSam's picture
SurferSam's picture
SurferSam commented Tuesday, 11 Dec 2018 at 8:10pm

Looks like version 2 of rpela now available with better test results https://www.rpela.com/rpela-v2-scientific-report-1/
Had version 1 and can say it was great in that you don’t really notice at all in the board when surfing. Was disappointed at the test results though. V2 looks better but still not perfect from deferent perspective

tubeshooter's picture
tubeshooter's picture
tubeshooter commented Wednesday, 12 Dec 2018 at 4:52pm

A link to recent estimates on White numbers by CSIRO etc.
https://www.australiangeographic.com.au/news/2018/02/groundbreaking-stud...
.Obviously a scientific proven trend cannot be verified at this point..But I think comparing white shark bycatch rates in today's commercial fishing world and those that pre-date catch limits, quota, fishing effort,, not to mention the culling of vessel numbers , crews , gear etc isn't a true reflection on numbers at all.

Imacie's picture
Imacie's picture
Imacie commented Thursday, 13 Dec 2018 at 11:44am

My idea is to have a fake orca floating around to act like a scare crow, and maybe combine that with some shark liver oil you can sprinkle as you paddle out.

blindboy's picture
blindboy's picture
blindboy commented Thursday, 3 Jan 2019 at 8:42am