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Archives for March 2011

Reflections on a fortnight in Fukushima

Richard Black | 16:15 UK time, Thursday, 24 March 2011

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Earth Watch posts have been in smaller supply than usual in recent days.

For a week, your humble correspondent was virtually living inside the Fukushima nuclear power station, attempting to make sense of what we knew and what we didn't know as the situation unfolded.

Now - almost two weeks after the devastating Magnitude 9.0 Tohoku earthquake and tsunami, and a few hours before heading on leave for a little while - it seems like an apt time to take stock.

Anti-nuclear protest

Fukushima has raised protests elsewhere in the world - how serious is another matter

In the broadest of senses, the situation at the power station itself appears slowly to be coming under control. Electrical power is progressively being restored across the site - no small task - and as time goes by, the rate of radioactive decay and therefore the heat output in the cores will naturally get lower.

Temperatures and pressures within some of the reactor containment vessels are well above the intended operating levels. A bulletin from the Tokyo Electric Power Company (Tepco) on Thursday put the vessel temperature in number 1 reactor building at 390-400C (734F), against an operating value of 138C (280F).

So the reactors themselves are not completely in the clear.

Nevertheless, the longer time goes by without any significant new development, the smaller the chances of something serious occurring.

It's important to point out a couple of things here.

Firstly, nothing definitive can yet be said about the sequence of events at the plant, nor about the response of Tepco employees in the critical early hours.

And it is certainly too early to make a comprehensive assessment of the health impacts. With the Windscale reactor fire of 1957 - like Fukushima, rated Level Five on the International Nuclear and Radiological Event Scale (INES) - the health consequences were still being assessed four years ago, on its 50th anniversary.

Fukushima will not take half a century to analyse because the facility has a civilian rather than a military purpose, because monitoring and knowledge of nuclear processes are far higher now than in 1957, and because the Japanese population is not likely to stand for it.

Destroyed petrol station

Operators have had to struggle with devastation from the earthquake and tsunami across the region

But at the moment, information is being disinterred bit by bit - and a truly comprehensive picture will in all probability have to wait on the first official inquiry.

The second point is that despite the allegations of secrecy and poor flow of information levelled against Tepco in the early days of the crisis, those allegations do not currently stand up to scrutiny.

The company is now publishing bulletins several times a day, sending them to reporters, responding to questions promptly and seriously, and posting mounds of data such as radiation levels on its website.

Whether the company is taking this stance entirely voluntarily or whether it has been dragged kicking and screaming by the government - whose leader, Prime Minister Naoto Kan, was possibly our best source of information early on - is not entirely clear.

And it cannot be proven that all the data we receive is entirely accurate. Nevertheless, this has to go down as a huge change from the situation seen at every other serious nuclear accident (by which I mean INES Level Five and above) in history.

At the time of writing, there are some intriguing tidbits.

Perhaps the most tantalising is a report by Kyodo News, Japan's principal news agency, to the effect that neutron radiation was observed more than a kilometre from reactor buildings 1 and 2.

Neutrons are emitted during a nuclear chain reaction; so given the context, is Kyodo's report to be taken as indicating that a chain reaction took place after the reactors shut down?

If it is, does that relate to the company's warning last week that there was a possibility of "re-criticality" in a pool storing fuel rods?

The neutron flux outlined by Kyodo - 0.02 microsieverts per hour - is within levels that are observed naturally in some locations - which raises the question of why it became an issue in conversations between reporters and Tepco representatives in Tokyo.

As I said, a tantalising tidbit; and a demonstration that in this story, every piece of information comes swimming in a sea of questions.

Meanwhile, what we are seeing away from the Fukushima site, in terms of restrictions on drinking milk and water and eating vegetables, recalls measures in place after Windscale and Chernobyl.

The big difference is that monitoring by Japanese agencies appears to have been prompt, informed and proactive, with results quickly disseminated to the public.

Milk being drained into field

Milk has had to be thrown away near the plant

Outside Japan, the big issue is what Fukushima means for nuclear power - and by implication, for plans to switch away from fossil fuels to restrain carbon emissions.

There are plenty of analyses around suggesting climate targets can be met through efficiency and renewables alone - Greenpeace's is one of them - but the political equation is more complex.

Imagine, for example, a decision at European level not to build any new nuclear power stations.

Nuclear is the basis of low-carbon electricity in France. Finland and the UK are among other countries committed to a partially nuclear future.

The question is not whether it is technically feasible to scrap those plans and replace the shortfall with wind turbines, solar panels and storage capacity - clearly, it could be done.

But would it be politically feasible? Given that we are past the era of state direction, will the private sector deliver on this scale?

On the other hand, utilities that are currently sounding pretty bullish about continuing with new nuclear build may look at things rather differently if public discontent manifests itself at building sites where new plants are scheduled.

On yet another hand, will Fukushima actually lead to serious public opposition? In Germany, it produced marches; but the UK public does not appear to have taken against the technology completely because of an accident on the other side of the world.

Perhaps a bigger practical issue than new build is how ancient plants should be regulated - what should be insisted on in terms of upgrading, given that safety practices have changed hugely in the 40-odd years since the Fukushima generation of commercial reactors came online.

How all this plays out cannot, I think, be predicted; and events will be fascinating to follow.

But at the present time, Fukushima can be used to bolster the arguments of either anti-nuclear or pro-nuclear factions.

One can - and is - saying, essentially, "you see - nuclear will never be safe - here's proof".

The counter is that if you exclude events in closed societies and those that took place in the 1950s, there have only been two nuclear accidents big enough to rate a Level Five or above - Three Mile Island and Fukushima.

No-one appears to have died in the first; and it is possible that the second will end with a similar statistic, given that workers unaccounted for at the plant may have come to grief in the tsunami rather than any nuclear cause.

Fukushima Daiichi was designed to withstand seismic ground movements of the scale that materialised during the Tohoku quake.

But it was not designed to withstand a 14m (46ft) tsunami - the latest estimate of the wave height that engulfed the plant two weeks ago.

So whatever governments and societies decide on the nuclear question, however they prioritise questions of energy security and climate change, it will have to be on the basis of relative risks; because nothing in this arena comes with certainties attached.

Bees: a sting in the tale

Richard Black | 14:13 UK time, Thursday, 10 March 2011

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Bee on flower

 

The United Nations Environment Programme (Unep) buzzes into the ongoing discussion of bee decline this week, with a report examining the global nature of the issue and some of the reasons behind it.

Their top-line conclusions are that it's becoming a widespread, if not quite global, phenomenon, and that there's a multiplicity of causes.

    Declines - and in some cases, sudden collapses - of colonies in Western Europe, North America and Japan have been widely reported.

    But it's perhaps not quite so commonly known that Chinese beekeepers "faced several inexplicable and complex symptoms of colony losses", as Unep puts it, or that collapses have also been seen in beehives along the banks of the Nile.

    As to the causes, the report highlights more than a dozen factors that could be responsible, in varying proportions, in different parts of the world, including:

    • diseases exacerbated by increased global movement of bees and of other things that may carry pathogens
    • agricultural chemicals
    • climatic factors
    • atmospheric pollution, which reduces insects' capacity to detect smells of, for example, important plants
    • loss of plant biodiversity, reducing the variety of bees' diet

    A while back, writing about the stark and global crisis facing amphibians, I suggested that the only factor to hold responsible was "everything" - and that the same might be true for bees.

    And this is basically the thesis that Unep is spelling out, through the scientific assessments of the Swiss, French and US experts enlisted to write its report.

    A recurring theme in Unep's work at the moment is the importance of "natural capital" - the goods and services that nature provides and that humanity makes use of - and Unep chief Achim Steiner was keen to outline how bees fit into this vision when he launched the bee report in Geneva on Thursday:

    "Human beings have fabricated the illusion that in the 21st Century they have the technological prowess to be independent of nature.

    "Bees underline the reality that we are more, not less dependent on nature's services in a world of close to seven billion people."

    And as concern slowly rises about the availability of food in the future, the UN report also floats the statistic that...

    "...of some 100 crop species which provide 90% of food worldwide, 71 of these are bee-pollinated."

    What to do about the problem is another matter.

    Given the mixed nature of the threat - a largely unquantified mixture - it's even debatable whether there is a single solution, given that simply returning the world to an era before agricultural chemicals, atmospheric pollutants and international trade is hardly feasible.

    Several governments have committed funds to research the problem; and when you consider that pollination is said to contribute $14bn (£8.7bn) to the US economy alone, you can see why the US government is one of the leaders here.

    Graph

    The number of healthy hives has fallen markedly in the US

    One of the questions to ask is why declines have been documented in the areas noted above, while in others - South America, Australia, most of Asia and Africa - there's no visible sign.

    From a practical standpoint, if you're faced with a complex problem that you don't completely understand but where there are some threats that are eminently addressable, then clearly it makes sense to deal with them while you wait for the scientific conclusions to come through.

    So in a number of countries, there are now projects - supported by industry or government agri-environment schemes or both - aimed at giving bees practical support.

    In the UK, farmers are encouraged to plant clover mixes and other bee-friendly plants around the edges of their fields.

    The Sainsbury's supermarket chain and even the Tate Modern art gallery in the heart of London sport roof-level hives and "bee hotels".

    Bee with varroatosis

    Diseases such as varroatosis are a major threat

    A number of European countries have banned neonicotinoid pesticides that they believe are implicated in bee decline.

    And bee-keepers internationally are bombarded with information about the need to keep their hives clean against varroa mites and other pests.

    None of these is likely to be a complete defence, but each is likely to give the insects something of a lift.

    There's a parallel here with coral reefs, which are likewise afflicted by a complex set of threats.

    So the question for authorities is what can be tackled, and what can't.

    The Great Barrier Reef Marine Park Authority might not have the power to stop global warming and ocean acidification.

    But it can restrict shipping and tourism, limit pollution from agricultural land, attack the voracious crown of thorns starfish and encourage fish that nibble on unwanted algae.

    Each of these will keep coral healthier and better able to withstand the threats that can't as yet be controlled.

    As Loretta Burke of the World Resources Institute said on the publication of a major global reef assessment last month:

    "There are reasons for hope. Reefs are resilient; and by reducing the local pressures, we can help buy time to find solutions to global threats that can preserve reefs for future generations."

    Unep's bee prescription is along the same lines, recommending the restoration of good habitat, low-input agricultural methods, and the provision of a diverse population of pollinators.

    Will it be enough? Or are we flying, slowly and inexorably, towards a world without bees?

    And if we are, what will that mean for the meals on our plates?

    Green tuna goes FAD-free

    Richard Black | 19:52 UK time, Wednesday, 9 March 2011

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    Environmental group Greenpeace is claiming something of a victory with the news that the UK's biggest supplier of canned tuna, Princes, is going to source its fish from more sustainable supplies than previously.

    Greenpeace tuna protest

    Greenpeace has been spearheading a campaign to get companies to adopt sustainable tuna policies

    A certain proportion of its tuna will come from pole-and-line fishing, while the remainder, from 2014, will come from fleets that pledge not to use fish aggregating devices (FADs).

    It's reportedly been joined by Asda, one of the country's principal supermarket chains, although at the time of writing the company hasn't got back to me to confirm.

    Greenpeace has been leading a campaign aiming to "name and shame" suppliers who don't put particularly sustainable standards on their tuna, and to stimulate consumer pressure to demand that shops up their game on the issue.

    Part of the camapign has been a "league table" of retailers - and at the most recent iteration, Princes came in eighth and last place, condemned for a number of apparent failings, including:

    • sourcing most of its fish from FAD-deploying fleets
    • not telling customers what species of tuna are in its cans or where they were caught
    • not giving public support to the notion of marine reserves in tuna-fishing areas.

    So the new announcement clearly marks a change. A company spokesman described it to me as "the next phase in Princes' tuna sustainability plan" - although to the environmental group's eye, it's a sharper change of direction than that.

    The announcement means that from now on, more than half of the canned tuna bought in the UK (which is the world's second-biggest market) will be supplied by companies signed up to a sustainable sourcing policy.

    Given the huge amount of publicity given to bluefin tuna over the last few years, it's important to point out that what we're talking about here isn't bluefin, whose delicate flesh is far too valuable to be imprisoned in tins.

    And indeed, the primary ecological reasons for concern are rather different.

    The biggest issue with the bluefin is simply that the species have been fished to the point of exaustion.

    Skipjack tuna

    The skipjack is one of the smallest tuna species fished commercially

    The main ingredient of canned tuna is the skipjack (Katsuwonus pelamis), a small, fast-swimming, fecund, gregarious species that is generally thought not to be significantly depleted, despite the huge fishing effort deployed against it.

    The problem is that skipjack are often found in close proximity to other tunas such as yellowfin and bigeye, which are in some trouble - the bigeye (Thunnus obesus) being listed as Vulnerable on the IUCN Red List of Threatened Species.

    Particularly when FADs are used, young bigeye and yellowfin are caught in the same nets that snare skipjack.

    FADs also lure sharks, many species of which are on the Red List - and these too are killed in the purse seine nets, whose modus operandi is to close like a purse around an entire shoal of fish.

    What to do? Well, it's a complex routine.

    The "gold standard" is to go fishing with a pole and line - one of the more traditional fishing methods, and perhaps the most selective of all.

    It also has the benefit of providing employment in developing countries - in the Pacific islands, for example, where much of Europe's tuna is caught - rather than allowing internationally owned and operated purse seine boats to reap the reward.

    But there are also constraints that make it doubtful whether pole and line fishing can supply all the tuna that Europe needs, let alone other parts of the world.

    We're largely talking about small boats travelling not too far from shore - which limits the area for fishing.

    We're also talking about a fishing method that needs live bait to attract the carnivorous skipjack.

    A study published just this month suggests that if the Pacific Islands were to provide all the tuna they currently do, but only through pole and line fishing, catching all the bait fish required would seriously deplete stocks of those species (such as sprat and anchovy).

    Tuna processing

    Tuna fishing can bring jobs and money where both are scarce - if managed well

    So although some suppliers are demanding fish caught by pole and line exclusively, it's not certain that this is a feasible answer across the board.

    Hence the decision of Princes to settle in part for fisheries that don't use FADs.

    These devices depend on a quirk of fish behaviour.

    Stick something big in the middle of open sea - a buoy, a big log, whatever - and many species will congregate around it.

    Why this should be so isn't entirely clear.

    One theory is that small species see it as a shelter from predation - meaning that bigger carnivorous ones have come to see floating objects as floating restaurants.

    Whatever the reason, you can now buy sophisticated buoys equipped with sonar and GPS.

    They can be despatched into the oceans, able to send skippers a continuous stream of data indicating where they are and roughly what volume of fish are gathered around - ideal for snatching up in a purse seine net when the time is right.

    FADs make highly efficient tools for fishermen - but they are highly inefficient at discriminating between different species.

    The thought is that in the absence of FADs, species will separate, enabling skippers to scoop out skipjack without touching the bigeye.

    Later this year we should see the start of trials testing prototype FADs designed to attract single species - more of that in a few months, I hope.

    In the meantime, what's the global significance of these moves within the UK? After all, its canned tuna market may be an important one, but it's still only a single country.

    Well, it's partly that the "dolphin-friendly tuna" campaign of the 1980s was one of the most effective environmental campaigns in living memory, bringing changes to the industry globally from its roots in the US - whatever caveats are raised about its ecological sophistication.

    In a sense, the current tuna campaign is a logical extension; and making it global would be a logical next step.

    It's partly, also, that companies in the industry are generally international. Asda is owned by Walmart, for example, Princes by Mitsubishi; practices seen as good in one branch of a multinational are liable to bleed through to the next.

    Thirdly, in order to supply the more selective shopper, suppliers will have to increase the scrutiny they put on their own work.

    Fishermen will have to label catches more carefully, and processors will have to maintain traceable supply chains.

    This builds the tools and structures that will be needed if and when other groups of companies want to adopt more stringent standards - or when other groups of consumers persuade them to.

    Is sustainable tuna in the can? Not yet... but it's filling up.

     

    China and EU share climate vision

    Richard Black | 14:57 UK time, Monday, 7 March 2011

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    China and the European Union are setting out plans for changing energy use and curbing carbon emissions within a space of a few days.

    As one of them is the world's largest emitter of greenhouse gases while the other would be third in the global list if its emissions were tallied as a single entity, what they come up with is obviously of some importance in shaping the world of the future.

    National Party Congress in Beijing

     

    The contexts of the two announcements are somewhat different.

    In Beijing on Saturday, Prime Minister Wen Jiabao unveiled his report to the National People's Congress, the Chinese parliament.

    In part he assessed progress on various measures over the last five years, and in part he outlined targets and aspirations for the five years ahead.

    (Time has posted English translations of the various documents that are downloadable and searchable.)

    Regarding energy and climate, one target is to generate 11.4% of energy from renewable sources by 2015 - up from 8% in 2010.

    Energy will be used more efficiently - about 16% more efficiently, on the same timescale.

    But by targeting economic growth just slightly lower than it's seen over the last decade, the Five-Year Plan also guarantees that energy use overall will still rise.

    The size of the targets probably shouldn't come as a surprise given that back in 2009, before the Copenhagen climate summit, China vowed to improve carbon intensity by 40-45% between 2005 and 2020, and to produce 15% of energy renewably by 2020.

    High-wire walker and power station chimneys

    European energy and climate policy is proving a difficult balancing act

    The Five-Year Plan targets are logical steps on the road.

    Back in Europe, the European Commission will on Tuesday unveil its energy and climate "roadmap" to 2050.

    This doesn't carry the weight of formal policy, because everything has to be signed off by member states.

    But because member states engage actively in lobbying and pressurising during the process of drawing up documents such as the roadmap, you can be fairly sure that what emerges won't be a million miles away from where nations will eventually converge.

    As I outlined on Friday, the commission is set to stick explicitly to its existing target of a 20% cut in emissions from 1990 levels by 2020 - ignoring lobbying from green groups who cite scientific studies to argue that after the recession, going for 20% is less ambitious than "business as usual".

    To them, the debate should be between 30% and 40%.

    There's clearly been a row going on behind the scenes between Connie Hedegaard's Climate Directorate and its Energy counterpart headed by Gunther Oettinger; and as of Friday, Mr Oettinger appeared to have emerged victorious.

    Nevertheless, there is at least a sense of the EU moving forward here - like China, driven partly by concern over climate change, partly by growing awareness of the insecurity of depending on fossil fuels, and partly by studies suggesting that a "green energy revolution" is positive for jobs and employment.

    In terms of what it means internationally, there's an intriguing phrase in the draft commission report leaked a couple of weeks ago:

    "Quite a number of the EU's key partners from around the world, like China, Brazil and Korea, are addressing these issues..."

    Given that the country traditionally closest to the EU on things political is the US, its absence from the list is telling in a couple of different ways.

    Firstly, it's another indicator that the US is not really moving forwards anything like as quickly as China and the EU on green energy and climate issues.

    As Time's Bryan Walsh put it:

    "At least they have a plan.

    "What do we have in the US? On Wednesday, Republican Representative Michele Bachmann reintroduced her Light Bulb Freedom of Choice Act."

    This seeks to repeal the 2007 Congress decision (made under the presidency of George W Bush) that from next year, only energy-efficient lightbulbs could be sold in the US.

    Aeroplane nose

    The shortage of alternative fuels for aviation means curbs will probably end up being tougher elsewhere

    As I wrote a couple of weeks ago, the US direction of travel on climate and energy is putting it out of kilter with most other countries in the world.

    Whether that matters for the US - and whether its basic premise is correct - are questions on which you'll have different views.

    But it certainly has implications.

    For example; if the Senate had passed climate legislation that included a cap-and-trade system, there's every prospect that the talk now would be of how carbon trading in the US could link up with the European carbon market.

    That prospect is apparently dead; and the most likely link-ups, that are even now being explored, involve Japan and China.

    The second way in which the "partners... like China, Brazil and Korea" phrase becomes important is over international moves to curb carbon emissions, and the notion - raised in that previous post of mine - that the rest of the world might not be as willing to wait for the US as it was in the run-up to the Copenhagen summit.

    Partnerships come in many guises; and there is a school of thought that says only now are European politicians understanding how to work with China, which is culturally so much more distant than North America.

    China's political process means that policies are largely decided centrally, at five-year intervals, after long discussions with interested parties inside the country.

    So perhaps there's no point in coming to an event such as the Copenhagen summit and expecting to negotiate on emission curbs, given that they tie so closely into economic policy.

    Perhaps instead the logical path should be to take the pledges that China makes (and other countries too) - and, accepting that they amount to targets that the government is totally serious about meeting, regard them as being equal to the internationally-binding targets that have been the traditional stock-in-trade of the UN climate process.

    We're due to see a more detailed and nuanced discussion of this idea emerge in a few weeks' time, so I'll leave it at that for now.

    In the meantime, we'll report on the European Commission's final document when it emerges on Tuesday afternoon, and wait to see what else emerges from the Great Hall of the People in Beijing.

    What sort of lightbulbs are in use there one can only guess...

     

    Refining the sixth great extinction

    Richard Black | 19:46 UK time, Wednesday, 2 March 2011

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    Are we living through the sixth mass extinction of life in Earth history?

    That we are is something you'll often hear asserted in conservation circles - and you'll easily find dozens of news articles taking the notion at face value.

    It's even acquired a posh name - the Holocene extinction.

    Woolly mammoth

     

    In this week's Nature, a team of researchers looks at all the evidence that's been assembled down the years and asks whether it's really happening.

    The previous "Big Five" events all involved, as far as scientists can tell, a loss of at least 75% of species in existence at the time - 96% in the case of the Permian event 250 million years ago.

    Are we really on a trajectory towards something that serious?

    Answering that question means addressing a huge number of subsidiary ones - notably, how can we tell?

    It's not a trivial matter.

    Assessing current extinction rates is difficult enough given that less than 3% of the world's known species have been formally assessed.

    Also, what do we mean by "current"? If the Holocene epoch is taken as beginning about 10,000 years ago at the conclusion of the last Ice Age, what tools can we use to assess extinction rates back then?

    The problems become even greater when you try to look back to the previous five mass extinctions.

    The fossil record is pretty much our only friend here, despite advances in molecular phylogeny techniques.

    And a patchy friend it is, given that only certain kinds of creatures are preserved in fossils, that only a fraction of the fossil beds existing in the Earth's crust are accessible for inspection, and that looking back to the earliest of the Big Five (the Ordovician event) entails making sense of evidence laid down 440 million years ago.

    Another question is whether you measure the speed - the extinction rate - or the number of species that ultimately disappeared - the magnitude.

    Chart

    The review concludes that the magnitude of extinctions isn't yet at Big Five levels - but that's only part of the story..

    Despite all these caveats and more, the authors (led by Anthony Barnosky of the University of California) do come to some conclusions, which you could summarise by saying that the amount of extinctions are not yet enough to make this classify as the sixth big one, but the rate of disappearance and the amount of stresses on the natural world suggest we are getting there:

    "The recent loss of species is dramatic and serious but does not yet qualify as a mass extinction in the palaeontological sense of the Big Five. In historic times we have actually lost only a few per cent of assessed species...

    "...current extinction rates are higher than those that caused Big Five extinctions in geological time; they could be severe enough to carry extinction magnitudes to the Big Five benchmark [of 75%] in as little as three centuries.

    "It is encouraging that there is still much of the world’s biodiversity left to save, but daunting that doing so will require the reversal of many dire and escalating threats."

    There are two big factors that separate the Holocene extinction from all the others.

    Firstly, it is the only one that is being driven by the expansion of a single species - Homo sapiens.

    Secondly, Homo sapiens is particularly attracted to saving things.

    So whereas the cataclysmic ends of the Ordovician, Devonian, Permian, Triassic and Cretaceous periods saw species become first rare and then extinct without any chance for salvation, now we are seeking where we can to keep the last remnants of many species alive, either in cordoned-off areas of natural habitat or in zoos.

    On the scale suggested by the Nature review, this isn't a feasible intervention; it may feel good, but it's barely a sticking plaster. If it's correct, tackling those "dire and escalating threats" urgently is the only way to prevent the mass die-off reaching Ordovician proportions.

    Otherwise, the Big Five will become the Big Six - driven by humanity's expansion, and achieved within a few human lifespans.

     

    Discard bathwater, not baby

    Richard Black | 15:20 UK time, Tuesday, 1 March 2011

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    Heron fishing

    More selective fishing tends to produce fewer discards

    Everybody wants to do it: nobody is entirely sure how that should be done.

    Discarding fish is, on one level, an outrageous practice; so surely stopping it is the right thing?

    A byproduct of measures to keep fishing within sustainable limits, discarding works against sustainability by ensuring that a good proportion of what fishermen catch is thrown back into the water - usually dead - thereby meaning that much more has to be caught than actually ends up on our plates.

    On another level, though, it's a necessary evil.

    Without quotas or some other way of curbing the extraction of fish, history suggests that the oceans would be sucked empty.

    And if fishermen catch outside their quota, they mustn't make money from it or else catching outside the quota becomes profitable - ergo, the fish has to be thrown away.

    That's why both fishermen and conservationists have welcomed European Commission ideas on regulating discarding out of existence; and why they are warning that doing so, while safeguarding both stocks and livelihoods, is far from a simple matter.

    (The EC document was not made public, but you can read it here.)

    The commission's basic idea is to find a mix of measures to regulate the fishery that includes quotas, restrictions on "fishing effort" (for example by limiting the duration of the fishing season) and closer monitoring by electronic and human observers.

    In the new world, quotas would be set for both intentional catch and bycatch (accidental take). So a boat targeting, say, haddock would be permitted to take cod as well, and to land it and sell it - up to a certain limit.

    So far, this is very broad brush stuff; and it's not entirely clear whether the commission will eventually propose a "one size fits all" package across EU waters or whether it'll be left to each government to select a mix appropriate to its own fisheries.

    Whatever the commission comes up with and whatever governments eventually decide, it's clear that other types of reform could also help make European fisheries a lot more sustainable than they are now.

    Trawlers

    More industrialised fisheries are associated with higher levels of bycatch, hence of discards

    Many kinds of selective fishing gear have been developed, using ideas such as escape hatches for non-target species, grids to select fish for size, and excluder or includer panels based on how different species behave.

    But fishermen have not always been enthusiastic about using them - even though they would reduce discards.

    In part that's because some entail extra costs without yielding extra profit.

    But in other cases, fishermen are clearly not taking even the simplest measures.

    The International Council for the Exploration of the Seas (ICES), which partly functions as the EU's scientific advisory body on fisheries, reported last year that boats in some EU waters were discarding 80% of the plaice and sole they caught.

    ICES remarked:

    "The high level of discarding in this fishery indicates a mismatch between the minimum landing size and the mesh size of the gear being used."

    Although this is a dig at fishermen, it's also a dig at European regulators who have repeatedly elected not to mandate selective gear anything like as systematically as they could have done.

    At the most extreme end, regulators could even mandate the end of trawling and the adoption of other methods that are inherently more selective.

    A review of global discard data for the UN Food and Agriculture Organization (FAO) in 2005 observed:

    "Shrimp and demersal finfish trawl fisheries account for over 50% of total estimated discards while representing approximately 22% of total recorded landings..."

    The same review hinted at the industry's optimum structure, concluding:

    "Small-scale fisheries generally have lower discard rates than industrial fisheries..."

    Amid all the comments and lobbying noises and observations flying around at the moment, it's worth perhaps returning to the basic reason why discarding exists.

    It's a byproduct of regulations that had to be introduced because the fishing industry has historically taken more from the seas than the seas can sustainably provide.

    That's the problem... so what's the solution?

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