Bluefin tuna are enormous and powerful, and are blessed (or not) with a with a deep red, fat-marbled belly loin. They make the best sushi, toro, and as such there is a massive market demand for their meat. Bluefin is traditionally eaten fresh in the Mediterranean, but the bulk of the global catch is frozen and shipped off to be eaten in Japan.

The northern bluefin population, which straddles the northern Atlantic and the Mediterranean, is now, thanks to all of this fishing, thought to be at just 15-20% of its historic abundance, although this exact fisgure has been disputed by some. Whatever the true percentage, the species needs a reprive from current fishing pressure to allow it to recover, with a full temporary suspension of fishing being the Holy Grail (but that is unlikely). In  response to ICCAT’s inability to manage the stock responsibly, the idea is to list the bluefin under CITES Appendix I, meaning that all international commercial trade will cease.

In Europe (in theory), this would mean fewer boats bringing in fewer bluefin to meet the relatively low consumer demand.  It should be noted that bluefin is not only caught for immediate dispatch on board, but also caught and towed in colossal nets to inshore farms where it is fattened up for a few months before market. These farms will be most severly affected by a trade ban than the straightforward catch-to-kill fishermen as they are much more geared towards international export. The situation would be similar across the Americas too (although there is less farming there).

Although this wouldn’t stop fishing of bluefin, the incentive to catch quite so many will have been removed because the catch couldn’t be traded, giving the stock some breathing room. While the producing nations and fishing communities would take a hit to their economy (and livelihoods, which politicians are so keen to avoid), those countries which rely heavily on imported tuna, such as Japan where demand completely outstrips national supply, the consumer would suffer without bluefin being flow in and sold in frosty auction rooms.

But this is where things become unsettled. There are ways around an international trade ban, the obvious option being the black market. Banning trade will not automatically cut down demand, and may instead push the trade underground. With the ‘classic’ endangered species like rhinos and tigers, illegal trade is attacked at both ends; by anti-poaching patrols at the source, and customs officers at the destination. Bluefin, which are fished in international waters, will have nobody fighting the fishermen off at sea (unless Sea Shepherd step in, although I’d rather they didn’t), and so countries like Japan would have to work jolly hard to crack down on the tuna black market. Despite this, and recognising that bluefin is served quite visibly in high street sushi restaurants, the current trade is bound to downsize somewhat. Greenpeace will no doubt be creeping around Tokyo with pipettes and DNA testing kits.

But there is another loophole which I find more worrying, as it requires no criminal activity by anyone. European and US vessels which are geared up to fish for bluefin tuna are registered to their national flag, but it is worryingly easy to re-flag to another country – Japan for example. If you fly the Japanese flag (with the necessary paperwork), your vessel is to all extents and purposes Japanese, even if you’re not. Trade is suddenly no longer international, and so the CITES ban wouldn’t apply.

Of course, there are pros and cons of re-flagging to the defecting fisherman, and full scale re-flagging is not a foregone conclusion, only a worry. Re-flagged vessels couldn’t land their catch directly in Europe or the States, or even supply live fish to the tuna-fattening farms (which are normally sat within national waters so the transfer of fish would count as international trade), so instead they would have to transfer thier catch to waiting transport ships in the Atlantic or the Medwhich would then steam off to deliver the frozen cargo in Japan. This does narrow the trade route quite substantially, but it remains that where there is demand, there is inevitably a supply, and some vessels will choose to exploit this loophole. Just how many remains to be seen.

I guess that in conclusion, a CITES listing for bluefin doesn’t necessarily guarantee its recovery. It might reduce the flow of trade, but a profitable black market will just make it a lot harder for conservation scientists to see is actually what’s going on, and loopholes will allow some fishing to continue. The listing does not tackle the root of the problem, which requires education amongst other things, and once again; where there is demand, fishermen will continue to catch fish. The alternative is to stick with the existing ICCAT management, which although currently inexcusable, may offer some potential if politicians listen to the advice of their scientists.

There is theory known as the ‘krill surplus hypothesis’, which is based on claims that the removal of more than two million baleen whales from the Southern Ocean in the 20th century meant more krill were available to minkes, boosting their populations (known as competitive release). As can be expected, the pro-whaling bloc have pushed this idea as a justification for continued hunting of minkes, but a new study may have just ruined their argument.

The study, led by Kristin Ruegg of Stanford University, took a genetic approach (which is fast becoming the sexy science-of-choice in conservation) and used DNA evidence to estimate historical minke whale population numbers, and compare this to today’s estimates. Large populations tend to have greater genetic variation than small ones (which have more inbreeding), so the amount of genetic diversity within a population shed light on its historical size. For Antarctic minkes, this long-term population size is roughly 670,000 and is well in excess of more recent population estimates. It would seem, therefore, that there has been no such modern boom in minke numbers.

This might be because krill have always been abundant enough to satiate all baleen predators, or that minke whales differ to other great whales in where and when they feed. Either way, it would seem they have not experienced any competitive release, and there is no evidence to suggest they should be managed as if they have.

Ruegg, K., et al. 2010. Are Antarctic minke whales unusually abundant because of 20th century whaling? Molecular Ecology 19(2): 281-291.

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17/02/2010    Just as a follow on from this, another genetics-based studyhas shown that the northern right whale, which numbers in the low hundreds and is thought to have been driven to the brink by ye olde whale hunters in past centuries (the Basques mainly), has in fact probably always had natually a  low(ish) abundance. The population has crashed from thousands to a few hundred, but not necessarily because of hunting. Read more on the BBC.

The unfortunate blobfish (c) CATERS

A creature’s existence value is a commodity, albeit a rather confusing one. To clarify, an existence value reflects the benefits we gain from knowing a particular ’something’ still exists. Each of us generates our own existence value for whichever species we care about, which is likely dependent on things like have we ever seen it, will we ever see it, or does it mean something to us in some other way. Needless to say, a species’ existence value probably diminishes over time too, depending on how much you liked it in the first place. The long and short of it is that different species have different existence values, and for the blobfish, or other similar deep sea enigmas, I wouldn’t put money on this being enormously high. Such species tend to be inaccessible, largely unheard of, and rather ugly. Cute and cuddly mammals represent the other end of the spectrum, and some would give their right arm to save them.

So do we care enough about the blobfish to want to do something about saving it, or should we just concede that its a unfortunate looking fish and we wont really miss it when its gone? Well, to be fair, this ‘existence value’ line of economic reasoning is perhaps a bit narrow. Blobfish have plenty of other ‘values’ which have probably been excluded from our individual outlooks, not least intrinsic value (meaning they have a self-worth just by being a blobfish), and instrumental value (meaning they might be a key player within the ecosystem). When it comes to deep sea creatures, public ambivalence is almost matched by scientific ignorance. For all we know the sky might fall on our heads if we obliterate our deep sea fauna. Given the fact that plenty of us wont have thought about this, or if we did then it didn’t do much to changing our opinion, should we be trusted to pass judgment on the blobfish’s fate?

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conservation |ˌkänsərˈvā sh ən|
noun
the action of conserving something, in particular;
• preservation, protection, or restoration of the natural environment, natural ecosystems, vegetation, and wildlife.

It would seem at the outset that conservation is a fairly straightforward process. Of course, in reality the art and science of conservation is muddied by difference in opinion and contrast in moral values. While this sounds an awful lot like a pessimistic statement, it does in fact make the nitty-gritty of conservation a lot more exciting!

I think it’s imperative that everyone has a view on the ‘hows’ and ‘whys’ of conservation. We base so much of our opinion on the gospel of heavily opinionated environmental NGOs, although these arguments are not always well informed, or even plain biased. During my writings on this blog I hope to challenge some mainstream conservation philosophy, and inject alternative or understated ideas and arguments in an attempt to make us all re-think conservation – me included.

Read on.