Big Sharks - Papers!

Source.

Apologies!

I've been posting fluff as I'm exceptionally busy - but several papers need urgent mentioning, so there!

First the GWS.

As everybody dealing with Sharks has known for a long time, Sharks do get cancer and more importantly, Shark cartilage is utterly useless in curing that disease. Finally, there's scientific verification of the former: here's a possibly first article describing tumors in Sharks, namely GWS' and Bronzies. And here's a synopsis with a funny quotable by DaSchiffman and a stellar pic by Ozzie Sam!

And, they live to at least 70 years!  

This is substantially longer than past estimates and finally confirms the intuition of many researchers and enthusiasts, with possible surprising differences in growth rates between males and females. 

Synopses here, here, and here!

And now the Tigers.

Much like described by several other authors for other oceans, the SoPac Tigers are equally highly migratory. Once again depending on individuals, they may be rather transient in coastal habitats and rather resident in offshore reefs, but then alternate those phases with large oceanic migrations, the latter especially by mature females. This paper by Jonathan Werry and others, among which my pal Eric describes such migrations between New Caledonia and Oz, and highlights the Chesterfields as an important pit stop and temporary habitat for adult males and subadult males and females.

Interview here, synopsis here.

And then, there's this.

Using mark-recapture, Meyer, Yannis and Co have estimated the growth rates and maximum lengths of Tigers in Hawaii. When it comes to the growth rates, this very much validates our observation that the smaller tigers grow incredibly fast, es exemplified by these two pics of Adi from 2005 (maybe 1.5m) and 2011 (a good 3m+), respectively.

Click for detail!

And the maximum size?

I am, quite frankly, highly frustrated!

Until now, I was of the opinion that Tigers could grow to 7m, possibly even longer - and now this: a paltry 4.6m in Hawaii and 5.5m globally! 

Frankly, not totally convinced.

Yes the 1957 record from likely Vietnam reported by Fourmanoir may well be unverified - but 50 years ago, we had not yet managed to obliterate the largest individuals of the largest species and with that in mind, it is not completely implausible. And let's also not forget the Shark culling programs in Hawaii that may have removed Sharks that could otherwise be larger now!

Obviously, those super sizes Sharks would likely be extremely rare, much like those fabled submarines - especially nowadays where they would have to be very lucky indeed to always manage to dodge the barrage of hooks we are throwing at them!
But like the GWS example from Oz and those new records from the Eastern coast of the US are showing, there's always the possibility of a surprise - or maybe one of those current 5m ones will have a better chance of growing even larger now that better management measures are slowly being implemented!

So fingers crossed!

Anyway, enjoy the papers!

Greedy evil Fishermen?

From the daily flood of images.

Malaita, Solomon Islands.

Chelsea Harris These ppl should be slaughtered the same way they are slaughtering our precious animals

Tamil Nadu, India

Inhambane, Mozambique.

Alberto Ruben Paredes Guerra Damn motherfucker...!!! I wanna kill him..!!

Drikie Strydom But dammit we need a Hitler to tackle the Chinese.. 

Just great isn't it - the images and the comments!

The cold fact is that for those local fishermen, those animals are nothing but a resource. The cold fact is that unless those fishermen are provided with alternatives and/or unless those resources are being protected or at least properly managed, the indiscriminate killing will continue.

And the frothy comments by the Facebook activists?

You may want to read Cool Hall Head's comment at the end of this op ed about the Canadian seal hunt and you may also want to read this piece about hypocrisy! 

Indeed, a class of sly racism colours these discussions! And it's not only the hypocrisy and the racism - the bloody noise and abject ignorance of both global and local circumstances is not only achieving nothing, it is actually only making things even worse! Case in point: read this surprising post on Rick Barry's EII blog - kudos!
 

As Chuck puts it in his inaugural post on SFS,  

sharks (are) finally closing in on the kind of conservation attention that has previously belonged almost exclusively to marine mammals....As a result, even conservation-minded fishermen feel like they have to oppose environmentalists, which just keeps the whole unfortunate cycle of opposition going. 

Indeed: welcome to the Dolphinization!

Solutions?

As always, they are no magic global recipes but one has to consider the individual local circumstances instead!

The Solomon Island situation is extremely complicated.

It touches on a whole gamut of issues, among which local culture and tradition, sustainability vs economical progress but also pure and simple greed and corruption at the village level, something we here know all too well from years of enacting conservation at the grass roots level.

It also touches on whether one should pay for conservation whereby everything unravels once the money stops flowing, or whether one should instead promote sustainable long-term conservation projects that pay for themselves, like we've done here. 

That's where the EII has ultimately failed as I see no indication of them having set up any viable long-term alternative, foremost of which the establishment of a local dolphin watching venture that could have provided for sustainable jobs and income. And their Dolphin-safe Tuna initiative? Re-read these posts!

And talking of which.
Does anybody still believe that what is happening in Oslob is Eco-terrorism?
Read this latest article!

The Indian example?

Quite obviously the Shark was initially merely accidental bycatch. Later ignorance, greed and cheating on the part of the fisherman concurred with a lackadaisical attitude by the competent authorities. Chances for the imposition of the Rs 25,000.00 fine so that subsequent fishermen will be deterred? Chances that these incidences will completely stop?

Mozambique?

Please re-read this and if you got the time, watch those videos and also the excellent Shiver - that's the backdrop and there are no easy solutions. Adam Baugh who has taken those horrific pictures knows it and has posted this insightful comment - kudos! 

In the end, it will come down to the commitment of the people on the ground and to whether the Mozambican government can be swayed into enacting adequate Shark management measures - and the way I see it (tho granted, I probably lack adequate insight), chances for the latter are slim indeed!

So what about Chuck's post.

I get and concur with the gist that demonizing fishermen is largely unfair and counterproductive - and yes, when conservationists work with fishermen, the results can be impressive indeed! 

At the same time, as somebody who has traveled extensively throughout the developing world and now lives and tries to enact marine conservation in a developing country, I'm frankly profoundly irritated by the continued apparent total lack of understanding by the SFS folks of the actual circumstances in those countries!

Yes the US (!) fishermen may be largely law abiding citizen.

But this only because they are being curtailed by gigatons of resources invested by NOAA and the NMFS! 

The truth is that when those very same people were not being regulated, they have done what all fishermen will ultimately do: they have caught whatever they could get their hands on and overfished recklessly to the point where some of them have fished themselves into extinction! That does not make them evil - it just makes them fishermen, perfectly respectable ordinary people pursuing their profession and trying to make a living,  tragedy of the commons, cheating and all!

Yes in theory, good sustainable management is better than prohibition.

But in practice, those developing countries do not dispose of the required resources and often also of the political will for adequate implementation, monitoring, enforcement and prosecution! Case in point: this post about Indonesia or this latest statement by a Fijian fisheries official. What does work are MPAs - small and big all the way to sanctuaries!

So for us guys trying to achieve what is possible given the specific circumstances on the ground, those continued statements on a science blog, let alone the sniping in the science journals are at least as unhelpful and irritating as the idiotic clamoring by the sharktivists that those statements are obviously aiming to counteract - the more so as the people making them are supposedly those with the superior brain power!

Love you guys - but you really gotta start thinking about the consequences of what you say!

And one last comment.

Beware of the romantic image of the noble savages pursuing artisanal fishing! 

That may have been sustainable a long time ago, when there were only a few people fishing with primitive means - but now those people are too many, the techniques have been modernized (do outboard engines and nylon gillnets still match the definition?) and above all, the cash economy has created a legion of small commercial as opposed to subsistence fishermen that catch way more than they need for their own consumption.

What has already happened in Asia where millions of small-scale fishermen have strip-mined the oceans and literally eaten the big Fishes into local extinction is starting to happen everywhere, with devastating consequences for biodiversity and ultimately, for those very coastal communities that depend on it.

Those small fishermen, too, are not evil. 

They are just trying to survive, often by whatever means they can find and apparently quite oblivious of the long-term damage (example here) they cause - or maybe they are just pretending to be oblivious and guess what, we'll never really know!
Obviously one of the solutions is awareness and education  - but let there be no doubt that these fisheries require the same degree of management and enforcement as the bigger commercial ones!

Anyway.

Like I said: less clamoring and dogma, more practical and pragmatic solutions for real and complex issues in a real and complex world!

PS Read his post before you go off on your next racist Facebook Rant about how, "brown and yellow people and raping the oceans"...they are not for the most part, what they are doing is surviving, and not in the twice-a-day Skinny Latte manner of Julie from Sea Shepherd (oh how she suffers for sharks), but in the classic, "don't have two dimes to rub together and my folks need to eat," sense.
Wow!

Sharks and Phytoplankton - full Circle!

Well well!

I really had to laugh out loud.

But first things first.

Anthony Marr thinks on a different level.

Having personally miserably failed every single physics exam that was ever thrown at me, I'm of the firm belief that a physicist's brain must be wired differently - and he is one of those. I also know that he must be preternaturally smart because I've consulted his YouTube channel and made an honest attempt at understanding his Omniscientific Cosmology and the like, and have come away with a migraine.
But I kinda get the gist - and guess what: once you strip away the New Age, the idea that we could reach a higher level by becoming a planetary unity kinda makes total sense. Never gonna happen - but it's a nice utopia.

Anyway, apart from being a messianic cosmo-philosopher or whatever, Anthony appears to be many other things, among which a respected and awarded animal activist.

And as such, he has posted a piece about the dreaded Phytoplankton.

It refers to this article in the SA which informs us that the Phytoplankton has declined by approx 40% since the 1950ies, possibly caused by the stratification of the upper ocean layers owing to the rise of sea surface temperatures.

Bingo!

And not only that.

Anthony has also regaled us with not one, but several infographics that he is busy disseminating among the sharktivist social media.

Here's one I like.

See the direction of the arrows?

So there you have it: Phytoplankton is the foundation of the entire marine food pyramid (for which it needs to get consumed!) and the production of Phytoplankton declines, all higher trophic levels all the way to the Sharks will be at risk!

No Phytoplankton = no Sharks - a bottom-up, not a top-down effect!
Talk about a total reversal of direction - and if Anthony says so, it must be true and guess what, I totally agree!

And this vital role extends to all the lower trophic levels like e.g. the Forage Fish and the Krill where we are fishing down the food web and further endangering the predators depending on them .

But that's another post for another time!!

PS: still eagerly awaiting Jessica's dissertation!
PS2: Marr vs the Mad Hatter? Now there's a thought...

Fishermen selling Sharks!

Nothing could be more ordinary.
This is what happens daily in hundreds if not thousands of small fishing ports world wide, in this specific case, Puerto Ángel on the Mexican Pacific coast. The guys just do what fishermen do, they fish and sell their catch. Nothing to do with perceptions let alone hating Sharks, they don't care about our ramblings and are just trying to make a buck. For them, a Shark is just a fish like any other.

Probably nothing to do with the proverbial insatiable Asian appetite for Shark fins, either.
The meat is being sold to local consumers and as long as somebody is paying top dollars, the fins are being cut off and sold to some trader and will eventually be shipped to Asia - and if nobody wants them, they will just be thrown away of fed to the dogs or whatever.

That's what we're up against - 7bn people many of which are poor.
They are protein miners who fish down the food web and now that everything else has been depleted, they catch and eat what was previously considered to be junk - tho specifically in Mexico, Sharks (and Mantas!) have always been on the menu.
Biophilia? Yes, in theory - but then, look at the track record.

Solutions?

Give them big Fish a Break!

Likely a big pregnant female - the worst possible loss for the stock!

Very interesting blog post!

It very much echoes a recent conversation I had with Doc where he told me that it is imperative to protect the large mature Sharks whereas in his opinion, a fishery for younger Sharks that would remain within the parameters of their natural mortality was at least conceivable.

Fish species channel their reproductive effort through three main strategies:
opportunistic species have a short life, grow quickly and produce many offspring (e.g., anchovies);
equilibrium species are long-lived, grow slowly and produce few young (e.g., sharks);
and periodic species are also long-lived and grow slowly, but produce many young (e.g., rock fish) [notice that salmonid and intermediate strategies have also been described].

For equilibrium and periodic species, a long life often implies a large body.
In terms of fitness, as an individual grows and ages, its chances of successful reproduction at least once in a life time increase, as though reproduction resembled a lottery whereby the older managed to bet more frequently than the younger (one side of the gamble). Equilibrium species bet a few descendants at each reproductive bout, whereas periodic species bet from thousands to millions. If reproduction fails one year, the long-lived individual can wait for improved conditions in the next year, e.g., more food, more mates, better environmental conditions.

Many multi-million dollar fisheries target relatively long-lived species, and it will be no surprise to find them on the menu or delicatessen section of our favourite restaurant or shop (e.g., tuna, cod, halibut, caviar [i.e., sturgeon]). That many harvested fish stocks worldwide show a temporal trend of decreasing body size indicates not only the selective removal of the largest fish, but also rapid evolutionary responses to compensate for (to escape from!) big-fish mortality, like retarding body growth and advancing the age at first reproduction.

Whatever the mechanism, if we target big fish then stocks become unpredictable and, what might be even more shocking, if we target only small or only big fish, the result might be population depletion all the same.
Thus, conservation of age structure seems to be the key issue. At an ecosystem level (beyond the coverage of this article), when overharvesting concentrates not only on the largest individuals within a species, but on the species that reach the largest sizes, i.e., apex predator species, we are actually ‘fishing down marine food webs’ (read it!) – one of the main anthropogenic impacts on global fisheries.

The main take-home message from Berkeley’s and other studies is that the assessment of stock recovery and exploitation must rely not only on biomass, but also on maximum age.

Fish populations and communities lacking their giants risk depletion and extinction.