Monday, January 07, 2019

Individual Shark Profiling? Yes and No!

Click for detail!

We're stuck inside waiting for Mona to unleash.

So there - have you seen this paper?
In essence and if I understand it correctly, it hypothesizes that Shark strikes are not a function of Shark density but that they are instead caused by specific individuals that are so disposed, e.g. possibly particularly bold  - and that as a consequence, the adequate management response would not consist in broadcast culling but that instead, one should surgically remove such problematic animals, much like what is being done with terrestrial problem predators.
And yes that person mentioned at the end would be yours truly.

So let me clarify where I really stand on this.

I agree with the hypothesis, albeit with caveats.
Ages ago, I penned this post about Shark strikes which I believe is still valid. In brief, the causes for Shark strikes are manifold =  whereas some of the interactions are due to predation or happen out of aggression and/or competition and/or self defense,  others are purely retaliatory or not at all driven by intention but simple mistakes (= NOT mistaken identity which is completely something else and  controversial) - and for these latter two categories, Eric's considerations probably would not apply. 
And anyway, for the large majority of cases, determining the specific intention of specific bites is obviously impossible and possibly also ultimately irrelevant.

But of course we can always speculate, see here.
And as somebody who has named, personally knows and spends an inordinate amount of time with individual Sharks and can thus observe their behavior, I can unequivocally confirm that they display great individual behavioral variability - and this very much including the propensity to bite!
In fact, among our Bull Sharks there is e.g. one particularly haughty lady who does not like to be touched and will always retaliate by trying to bite us when we do so; or there is another one, a small male, who despite of many years of hand feeding, appears just simply too stupid to understand the proper etiquette and always comes in too low and too fast, and is thus a constant safety risk to the feeders. Same-same for a specific Gray Reefie who has repeatedly bitten the hands of our feeders - and thank you for bodyguards and especially, for steel gloves!

And then there is XYZ (name withheld).
This is a very large female Bull Shark who can only be described as being sinister and dangerous, this insofar as she is extremely assertive, will frequently approach us closely and not in what we perceive as a friendly way, and needs to be fended away and dominated.
And one day, and I believe because she was cranky for having lost a dominance confrontation with another big female, she has already bitten one of our staff who was incidentally not in the slightest inconveniencing her; this in what I personally interpret as Übersprungverhalten or displacement behavior, or maybe simply the venting of accumulated aggression. Again, we will obviously never really know - but she is certainly an animal of concern.

And when it comes to those predatory strikes.
They are fundamentally different from the examples above as IMO predation = feeding got nothing to do with aggression and/or boldness, and why would it.
But I absolutely believe that some Sharks will sometimes target and consume a human; and I also absolutely believe that given what we know about their learning capabilities, ontogenetic dietary shifts and their individual behavioral variability, we can also absolutely not exclude that this or that individual may develop an individual propensity (or reduced aversion) for targeting humans, which is what Eric appears to postulate.
Yes this is obviously speculative and so far unproven (and likely untestable) - but it is I believe at least plausible - and as long as it is, and as long as it not actually disproven, it is also not false! 

And remember this shit
It mentions, and even depicts that ominous OWT who has been alleged to have bitten no less than three people - and this by so-called Shark experts in a so-called peer-reviewed scientific paper !

Anyway, back to Eric's paper.
Yes in theory, there could absolutely be individual Sharks with as propensity to bite humans; and yes in theory, selectively eliminating those would absolutely be preferable to indiscriminate culling!
So I absolutely support it as a theoretical approach to mitigating Shark strikes! 

And in practice?
Unfortunately, there prospects for success look totally unrealistic.
In terrestrial habitats, identifying, monitoring and managing individual animals is comparatively easy - but doing so in the ocean is obviously a completely different matter as the territory is immense, there are thousands of Sharks leading a life that is essentially cryptic as for human observers, everything happens "out of sight" - and thus, identifying, monitoring and then eliminating the individual perpetrators as suggested would generally speaking be extremely expensive and logistically extremely onerous if not outright impossible.
With that in mind, the suggested list of measures aimed at identifying problem individuals, albeit certainly erudite, is more pie in the sky than a viable recipe for success. Or should we e.g. really try and catch, tag and tissue sample every single large predatory Shark in Australia - and then try and catch a single individual perpetrator after a strike?

And, when, exactly, would one effect the removal.
After a first bite? After two or even more? Lethal bites or not? Or would one remove the Shark preemptively already upon identifying a problem in behavior, or e.g. undesired levels of testosterone or cortisol?
And before the removal, whatever the latter means, one should obviously first try other approaches akin to e.g.the hazing and/or other deterrents and/or protections and barriers one would be using in terrestrial situations - correct?
Detail detail!

But of course there could be exceptions.
Specific circumstances obviously vary, and there could be individual, albeit probably rare conditions favoring Eric's approach.

Examples?
The situation with our above-mentioned XYZ could e.g. escalate to the point whereby despite of our best efforts in trying to deter and/or train her, we would have to come to the conclusion that she is becoming too much of a safety hazard. 
Then, we could be forced to choose between either closing down our Shark viewing operation or selectively removing her.

Or take e.g. Cocos.
Remember that Tiger and then, this subsequent event?
Yes this is completely speculative - but considering how well the good people of GSD member Undersea Hunter Group know their Sharks: what if they were able to determine that it was the same, individually known individual? 
If so and considering the risk of further attacks vs the tourism income: could this maybe escalate to the point where the park authority would have to make a decision?

And finally, Reunion Island.
There, the comparatively small territory and likely comparatively small number of potentially dangerous Sharks that could thus be potentially identified individually may well warrant trialing Eric's approach - this particularly in view of the ever-persistent calls for more Shark culls!
Or not?

But again, these are rare exceptions.
In the overwhelming majority of cases, Eric's suggestions, albeit intellectually interesting, are just not sufficiently practicable for them to constitute a viable alternative strategy.
Alas!

And finally, what about this beauty?
I can only note that Neff the token Shark attack apologist remains as predictably irritating as always, the more as his arguments are little more than straw men.
  • Yes the hypothesis by Victor Coppleson of there being "Rogue Sharks" has not been proven - but a) as per above, the fact that something has not been proven does not necessarily mean it is false, either and b) Eric expressly differentiates his hypothesis from it. 
  • Yes as per above Eric's hypothesis does not apply to all Shark bites - but that does not invalidate it a priori!
  • Yes often when asked, the public does not support Shark culls - but a) they continue to happen and b) more importantly, Eric does not at all advocate them but on the contrary, he obviously sees his approach as an alternative to them!
Anyway, all very interesting indeed.
And in the meantime, Mona has come and gone. And we are doing just fine thank you.

Let's go Shark diving!

PS - Bingo...
PPS - Michael here - thanks!
 

No comments: