Time for a rant!
From a message by a friend
Agree that there is much breathy hyperbole and blatant nonsense written about sharks and conservation, but I suppose that this is inevitable when concern is high but facts are few, with the most solid data residing in relatively inaccessible scientific papers.
Generally I take a sanguine or even charitable view toward the popular Jeremiads you have castigated since the goals of the authors are generally in concordance with mine, and these often painfully well-intentioned folks are far more able to communicate values effectively and educate a large audience than someone who uses words like sanguine or Jeremiad, no?
And education does seem to work in the long run.
Totally agree – BUT!
I’m getting terminally irritated that people who purport to be Shark conservationists and are perceived to represent the whole movement continue to make public statements containing ludicrous assertions and statistics.
This is not only not helpful - it directly undermines our efforts by allowing the other side
to assert that we’re nothing but a bunch of lunatics who operate with false claims.
Is that what we want?
Yes it’s an
old grievance of mine – but enough is enough.
So there.
But first, check out this piece of equine manure!
Very timely indeed – thank
you!
Wow!
Pure
sharkitarian snake oil!
There are no Shark attacks?
Right!
Please re-read
this!
Sharks?
When talking conservation, talking about “Sharks” is utterly
useless!
The fact is that
“Sharks” are neither threatened with extinction, nor are "they" apex predators – only a small minority of species are apex predators, let alone keystone species, and the species that are particularly at risk of extinction are several large predatory Sharks, many of which are
pelagic; possibly some deep water Sharks; and maybe Whale Sharks – full stop!
Other species are doing no better and no worse that any other Fish that is not subjected to exceptional fishing pressure – meaning not particularly great but not particularly catastrophically, either.
List
here (search for "Sharks"), criteria
here.
The numbers?
The numbers are just that, numbers.
If one does not put them into context by comparing them to what we know about
individual species in specific locations,
they say nothing about sustainability which is the
only thing that counts.
Yes we all know without having to resort to peer reviewed science that many local, and possibly even some global populations of some Sharks have been severely depleted, and that their disappearance is of concern – but for the time being, that’s basically all we can assert.
So far, there has been
one single paper trying to shed a light on the actual numbers being caught, and this
only based on data from the Shark fin trade.
Read it!
The paper is based on a series of (probably plausible) assumptions that are heaped upon more assumptions, and consequently, the results are merely expressed in orders of magnitude. Specifically, the authors come to the conclusion that the fins traded annually came from between 26 and 73 million Sharks,
with a median number of 38 million.
Does that really allow us to honestly state that
up to 73 million Sharks are being killed each year, as everybody and his dog has started to assert?
Kudos to Seafood Watch for doing it right:
It's estimated that tens of millions of sharks are killed around the world each year for their fins is much better - but then again, have they been killed
for their fins?
As I said, the above numbers are only about the global Shark fin trade alone.
They do not cover many other Shark fatalities due to bycatch or targeted food fisheries where the fins are not being introduced into the fin trade.
Also, that was then and the trade has very likely increased since. It is thus entirely plausible to assume that the “real” number is higher, and it is perfectly OK to say so.
It is however totally unacceptable to make up numbers on the fly, be it
as many as 100 million, let alone
over 200,000 million (!!!) which is just plain ludicrous and quite frankly, a total disgrace! Yes, I'm being frank! :)
The good news is that I know that somebody is working on a peer reviewed paper about the global number of Shark being killed – but once again,
unless put into context, those numbers will mean absolutely nothing!
And what about the
Rate of Depletion?
Is it really true that 90% (or 99, or 70 – whatever!) of global Shark stocks have already been wiped out? Compared to
which original baseline count, done when, where and by whom?
Where are the data?
And is it really true that Some marine biologist have suggested
as soon as 2020 these magnificent creatures may be extinct – and if so, who is claiming such utter baloney?
Those endangered species of Sharks will become commercially extinct long, long before they will become biologically extinct! But there's a caveat: it is however probable that
some local populations may have shrunk to the extent that they may have accumulated
extinction debt and that they may be too small to be able to withstand the pressure of a large environmental shock, like the current
anthropogenic Climate Change – re-read
this post!
Shark Finning?
Shark finning does not equal catching Sharks. It is a specific, particularly wasteful and particularly cruel harvesting technique and for these reasons alone, it certainly needs to be stopped.
But is everybody aware that stopping the finning does not necessarily stop the fishing? The most widespread remedy against Shark finning is to legislate that the Sharks must be landed with their fins attached. This reduces the number of Sharks that are being killed as the carcasses take up a lot of space in the hold of the vessels – but as many examples show, Sharks are still being landed
with their fins attached in what clearly appear to be unsustainable numbers.
Also, in many third world countries, local fishermen (and poachers!) have already wiped out many of the traditional food fisheries and as a consequence, many people have
added Sharks to their menu, meaning that there is a substantial and increasing Shark food- , as opposed to Shark fin fisheries.
Thus, if we want to save Sharks stocks from overfishing,
Stop Shark Finning! petitions alone are simply not adequate –
we must also campaign for their protection!
Also, not every fin that is being sold has been finned!
Statements like
over one hundred million sharks are caught and finned alive are thus doubly misleading!
Cascading Effects?
Yes there is a
seminal paper by Myers et al. that essentially shows how the removal of large predatory coastal Sharks in the Northwest Atlantic led to the explosion of the population of Cownose Rays who in turn wiped out the Scallops, and the industry depending on them, in Chesapeake Bay. More details
here.
Great paper – but it has one weakness:
nobody was harvesting those Cownose Rays!
But in the real world, coastal Sharks are not being selectively removed alone.
Instead, fishermen target both the apex- and the mesopredators (and the prey), meaning that asserting that removing the big Sharks will
inevitably lead to a population explosion of mesopredators (many of which are incidentally Sharks!) who in turn will wipe out the grazers which in turn will lead to an explosion of algae who in turn will smother the reefs can be totally wrong.
In a way, it is now us who have unwittingly assumed the role of apex predators and are keeping the lower trophic levels in check – see many terrestrial habitats where most apex predators have all but disappeared but where there has not at all been
a total collapse of the system!
I’m not saying it is not so: I’m just saying that the empirical evidence is scarce and that once again, those effects will vary according to habitat and species composition.
See
Ferretti et al. for more details!
As to the role of Sharks in their habitat and the widespread explanation that
they weed out the sick and dying and thus keep the gene pool of their prey healthy, etc?
Certainly intuitively plausible: but to my knowledge, whereas there is plenty of research about the role of terrestrial predators, such effects have not been conclusively documented for Sharks – yet!
Which brings me straight over to
Climate Change and Oxygen Production!
Check this out.
Did you hear that?
Who has come up with the glorious idea of linking Shark conservation to the Oceans’ production of oxygen?
Yes the Oceans provide for about half of the planet’s oxygen production through the photosynthesis
by phytoplanktonic Algae and Cyanobacteria (but then again,
probably not!). This (incidentally, to a
very small extent), and the sea water’s capacity to dissolve CO2 make it that the Oceans are also
Earth’s largest active carbon sink.
It is also certainly true that the Oceans have a great influence on the weather, and that millions of people depend on them for food.
But this got nothing to do with Sharks!
The principal threats to oceanic ecosystems are probably Climate Change, Acidification, Overfishing, Pollution and Habitat Degradation – not the fisheries for Sharks!
It is just not plausible and there is certainly no scientific evidence indicating that if one selectively removed all Sharks
- the oxygen production would cease due to the disappearance of phytoplankton
- the oceans would cease to be a carbon sink
- the weather would change
- fisheries would collapse and humankind would starve
or any other similar stupidities that happen to be
en vogue among some Shark activists!
Shark Intelligence?
This very much smells like the newest up-and-coming Shark conservation fad.
Does the fact that
some Sharks migrate and that they are
capable of memorizing locations automatically mean that they are particularly intelligent? Why are some quarters
asserting that it is so, when this is in no way being claimed by the authors of those migration papers?
Sorry Richard – I still think you rock! ;)
Are
Monarchs particularly intelligent?
Wildebeest?
What about Bees who are not only capable of finding and memorizing the location of a food source, but then also fly back to the hive and
convey that information to the other bees – so effectively. that those other bees can find the food without being guided there by the finder?
Hell, that’s even smarter than what we know about the so much hyped Dolphins!
Frankly, I dunno.
My gut tells me that migration and spatial orientation are not good indicators for intelligence. Yes it is amazing behavior – but animals doing amazing things are more often than not simply well adapted to their ecological niche, and behavior that comes across as being remarkably clever is often hard wired and the result of evolutionary selection as opposed to volition.
Example? The amazing
Anglerfish!
Perfectly camouflaged and provided with an ingenious lure, they are highly successful at ambushing their unsuspecting prey. Totally clever – and yet one of my ichthyological gurus assures me that they dispose of the lowest
brain-to-body mass ratio of all Fishes!
Sharks BTW have a relatively high brain-to-body mass ratio, somewhere between Teleost Fishes and Mammals..
But although we all intuitively know what intelligence means conceptually, it is nevertheless difficult to
define, especially
in animals - and even more difficult to compare, see the Bees and the Dolphins!
When it comes to Sharks, the one person who knows most about the topic is probably
Doc who has demonstrated remarkable learning and problem solving capacity in Lemons, very much in line with what we experience daily with our Bulls.
My gut feeling is that as always, different species will display different abilities, and that those predatory species with the widest trophic niches requiring the widest range of predatory strategies and thus the highest adaptive capabilities will be perceived as the most intelligent - but then again, a friend may be on to something when he remarks
Incidentally, since humans filled a generalist predator niche at one time before we graduated to planetary predator class, would we not inevitably tend to think that other generalist predators like sharks are particularly intelligent?
Yes, it's complicated!
Still, I fully agree with
Wolfgang that Tiger Sharks come across as being way smarter than, say, Whale Sharks that I incidentally perceive as being particularly dumb - and who incidentally migrate like crazy!
But those are clearly personal perceptions, not objective data.
Whereas I’m convinced that all of our Bull Sharks have distinct personalities and that they develop affinities to specific persons, I also know that we humans have a fatal propensity for anthropomorphism, i.e. for attributing human faculties to animals.
So, yes, let’s love them like crazy – but let us not assert that our feelings are being equally reciprocated, or the like!
Yes
Emma very much appears to love Jim (and there’s absolutely no doubt whatsoever that Jim loves Emma!) – but she is very likely being bribed with massive amounts of juicy handouts and is just being the opportunistic feeder Tiger Sharks are!
Having said that, there appears to be clear evidence that the behavior of some Sharks goes well beyond that of mere automatons that are solely driven by genetic programming.
In fact and going back to, say, Tigers and Bulls, aren’t high flexibility and adaptive capability precisely what we would expect evolution to select for in a generalist predator – meaning that some of what we perceive as being intelligent behavior may be genetically encoded, but that there must also be scope for individual decision making, individual learning, individual preferences, individual personality, etc. which may indeed be good indicators for intelligence.
Again, I don’t know - but precisely because of that, I would never proffer any strong statements one way or the other!
Long story short?
If we want to be credible Shark advocates, we got to do our homework and first of all, be informed about the animals we love!
Science is always in flux and today’s insights may quickly become tomorrow’s fallacies, meaning that we must keep abreast of the latest research results and not base our knowledge on old publications and approximate hearsay.
Most importantly,
we the amateur naturalists should never make up things on the fly, nor should we idly re-interpret what is considered to be the accepted consensus.
This does
not mean that we should not challenge the current
status quo, as that is precisely the process by which knowledge is being advanced!
BUT: the only accepted technique for doing so is the
Scientific Method and as always, let me warn against the siren calls and intellectual shortcuts of the self promoters, quacks and charlatans - see on top!
All researchers I’ve ever met have always been eager to engage in informed discussions and to entertain different hypotheses, if adequately supported by according observations.
Those researchers are neither omniscient nor omnipresent and often, observations by common mortals like us have greatly contributed to the advancement of scientific insights - so even if you have no academic background, don’t be shy and speak up!
But do your home work first!
Or, as I said
before .
Can we maybe just be a little more humble and less righteous, the more since Conservation is so complicated?
Maybe progress towards more facts and less
truthiness (read
this!)?
Can we maybe just open our eyes and wonder at the magnificence of what IS instead of trying to make things up?
We are the amateurs.
Can we please listen to what the professionals are telling us – the principal message being that
extreme positions (on both sides!)
are inhibiting Conservation and appropriate Management measures?
Recent example? Right
here – like it or not, the man has a point!
If we want to educate others – let’s educate ourselves first!
And here endeth the weekend rant!
PS
Patric's take: WOW!!!
