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Archives for February 2011

US climate cuts threaten isolation

Richard Black | 11:35 UK time, Thursday, 24 February 2011


The latest flirtations of the US political right with "climate denial" look set to marginalise the country even further within the global community of nations - at least when it comes to climate change.

Diego Garcia coral atoll, in the central Indian Ocean

Does the US risk isolating itself from the global community?

The key to all this is the advance made by the Republican party - and by relatively right-wing Democrats - during the mid-term elections late last year.

With a majority in the House of Representatives, politicians unconvinced of the case for action on climate change have been able to attack the edifices of climate science and international negotiations in quite dramatic ways.

Budgetary measures passed by the House at the weekend would not only withdraw US funding from the Intergovernmental Panel on Climate Change (IPCC) - they would also end financing for the office occupied by Todd Stern, the experienced official who leads US diplomacy within the UN climate convention (UNFCCC) and other fora.

Before these measures could come into law they would have to make it through the labrynthine processes that precede a US budget agreement, including being approved by the Democrat-controlled Senate and signed off by President Obama.

So, you might conclude they'll never make it.

Equally, remembering that they'll be relatively minor ingredients of a vast budgetary package whose negotiation will require extensive horse-trading, it's easy to see how they might make it through these various hurdles if the Democrats judge they're more expendable than other items.

The claims used to back the proposed IPCC cuts are easily countered. Launching his "de-funding" amendment, Congressman Blaine Luetkemeyer described the panel as:

" entity that is fraught with waste and fraud, and engaged in dubious science..."

E-mails taken from the University of East Anglia's Climatic Research Unit (CRU) in November 2009 showed, he said, that:

"...leading global scientists intentionally manipulated climate data and suppressed legitimate arguments in peer-reviewed journals. Researchers were asked to delete and destroy e-mails so that a small number of climate alarmists could continue to advance their environmental agenda."

The IPCC has never been found fraudulent by any investigation - indeed, successive reviews, notably by the InterAcademy Council, have found just the opposite.

That being so, to make the allegation outside the legal protection afforded by the political process would potentially lay the speaker open to action for defamation.

Neither has it been shown that UEA scientists intentionally manipulated data - again, the opposite conclusion is eminently more defensible - nor that they had an "environmental agenda".

While criticising proponents of climate action for basing their policies on dodgy ground, Mr Luetkemayer apparently had no problem making allegations demonstrably lacking a factual basis.

You might also ask where the notion of consistency has gone, given that when Sarah Palin's e-mail account is hacked, the Republican party condemned it as "a shocking invasion of privacy and a violation of the law" whereas the same entity apparently brings no criticsm of the hacking of CRU servers.

Nevertheless, this is politics - and facts have always proven to be malleable in that particular furnace.

So what would these measures mean if they all went through?

The IPCC sums are minimal - about $3 million per year. A large proportion goes to fund the Technical Support Unit (TSU) for IPCC Working Group 2 - the group on impacts, adaptation and vulnerability, one of the three principle strands of IPCC research.

As the group currently has a US-based co-chair, Chris Field from the Carnegie Institution at Stanford University, the US gets to fund the TSU - the small team that supports the scientific assessment.

With the money gone, the TSU would either have to find another source of funding - which might not be too hard in a US awash with charitable foundations signed up to the need to curb climate change -or, more provocatively, move to Argentina, home of the group's other co-chair, Vicente Barros.

IPCC working groups always have one co-chair from a developed nation and one from a developing country, and the richer partner has always hosted the TSU - which in some peoples' eyes has given too much priority to western concerns.

A switch to the poorer partner - and Argentina is surely rich enough to host a TSU if it wanted - would be a new tweak and one that would reduce US influence over the IPCC's next report.

The House's budgetary bill seeks to lop far greater sums from the climate science budgets of US agencies such as the National Oceanic and Atmospheric Administration (Noaa).

Cuts along these lines would also weaken the US voice as its dominance in climate research waned.

Putting Mr Stern's office off-line, meanwhile, would significantly curb US influence within the UN climate negotiations.

Critics say its main role recently has in any case been to stall and weaken... but it has been engaged, and undoubtedly highly influential.

At the recent Cancun summit, Mr Stern's delegation implacably fought for and won on a number of points - notably securing World Bank influence over international climate finance in the teeth of vehement opposition from developing countries.

There would surely be a risk that trimming the US presence in the UN process would weaken its capacity to influence such matters.

Mr Stern and his deputy, Jonathan Pershing, have stuck to the line that the US administration will not sign a treaty that the Senate will not ratify. Recently, they've suggested that for now, governments should stop looking for a global deal and concentrate on delivering the unilateral voluntary pledges they made around the time of the Copenhagen summit.

This - though undeniably realistic, given the way political winds are blowing in the US - is also leading some movers and shakers in the UN climate process to question whether they should plan for an immediate future that explicitly leaves the US to one side.

A strategy could be adopted that basically ignores the world's biggest economy - though, of course, leaving a window through which it could re-enter if and when the political winds change.

How this might work and what some of the alternatives are I'll return to in another post.

All of this must be galling for Mr Pershing, especially.

In 2008, before taking up his current post and while working for the World Resources Institute on its climate programme, he argued:

"The Bush administration has avoided significant climate change policy, leaving the US so far a largely ignored observer at these international negotiations... The US holds the key to a succesful global climate change treaty."

Current events suggest the political clock may be turning back faster than anyone thought possible when Barack Obama swept into the White House pledging "global leadership" on climate change.

This time, however, the political landscape is different; and perhaps the US doesn't any longer hold the key to a treaty.

No longer is it the world's biggest emitter. No longer is it the most powerful political entity on the scene - that role has been taken by the BASIC group (Brazil, South Africa, India and China).

And climate science - despite Mr Luetkemeyer's interpretation - has hardened, with real-world changes that look very like the signatures of greenhouse warming being registered from the Arctic to the Amazon heightening the concerns of vulnerable nations.

Will the rest of the world wait for the US again - as it did in Copenhagen - especially when its political leaders are apparently bent on downgrading its importance in the climate arena?

War and peace: Making sense of climate conflict

Richard Black | 18:49 UK time, Friday, 18 February 2011


It must have seemed a good idea at the time; to get a group of people together from "both sides of the climate debate", put them in a room for a few days, and see whether peace would spontaneously break out.

It's worked with apparently thorny issues such as nuclear arms control, it's failed with others - notably, and repeatedly, Middle East peace.

Fight in the Ukraine parliament

Politics can be a passionate business

The meeting I'm referring to took place a few weeks ago in Portugal.

I first read about it on the New Scientist blog written by Fred Pearce, who was there; and as Fred relates, there doesn't appear to have been a magical exchange of olive branches.

There may be many reasons for that, but one is central, fundamental and simple - a truism explained to me many times down the years by experienced negotiators.

Essentially, you can only make deals and make peace if everyone involved wants to.

Apply that to the bitter world of climate politics and... what do you think the chances look like?

You have genuinely held differences, some regarding interpretations of science and some regarding political philosophies.

And while the former ought in principle to be capable of resolution, there's no reason why political factions should agree on anything - in fact in this case, they're actively lobbying for very different sets of policies.

So while you might expect little meeting of minds, what emerged was something even worse, at least from Fred's point of view - finding himself subject to attack from "warmist" bloggers who accuse him of having made things up to discredit one of the invited scientists - Nasa's Gavin Schmidt, a prominent climate modeller and a bete noire of "sceptical" bloggers.

The messenger, too, is painted as a combatant.

So much febrile heat; so little light.

This is familiar stuff in the political world where part of the job description is to be able to give and take knocks without complaining - some of the best politicians, in fact, revel in the scrap.

But it's not the way science is: nor, I would suggest, the way it ought to be.

Penguins on the Antarctic coast


The issue is illustrated again by a row over temperature trends in Antarctica.

Almost exactly two years ago, a research group led by Eric Steig from the University of Washington published a somewhat controversial analysis of the Antarctic temperature record.

Their analysis suggested that the giant frozen continent had, on average, warmed up over the last half-century - clarifying a picture in which other studies had produced various accounts of trends in different parts of the region.

I say "controversial" because the team, acknowledging that there wasn't as much data as they might have liked, used various techniques to produce data that instruments would probably have generated if they had been in existence (that's the best lay description I can muster, but around the time of publication Eric Steig wrote a fuller description on RealClimate, the website to which he and Gavin Schmidt frequently contribute).

Shortly afterwards, RealClimate noted that a blogger called "Ryan O" had posted a new analysis he'd done that showed, he claimed, flaws in the Steig study.

That blog eventually turned into another scientific paper that has just been published in the Journal of Climate - "Ryan O" turning out to be Ryan O'Donnell.

Well - so far, so good, you might say.Researchers are doing what researchers do - using different methods to reach differing conclusions, putting them into the scientific literature and allowing the research community as a whole to sift and sort and decide, in time, what is wheat and what is chaff.

Except that outside the strictly scientific corridors, an almighty row has blown up over who-said-what-to-whom.


Tempers grew pretty hot over the icy continent

Eric Steig was one of the experts the Journal of Climate called on to review the paper before publication, and has been accused of trying to block it - which he denies.

You can read the whole account elsewhere - mainly on the pages of RealClimate and ClimateAudit - if you want to.

Or you can read the potted version from jcmmooreonline  - or you could short-circuit the lot and go straight to the contribution Andy Revkin of the New York Times highlights on his dot.Earth blog from Cornell University's Louis Derry, himself a journal editor.

It's the most cogent, no nonsense account I've seen.

And the most cogent point in it (which he doesn't highlight, but I will) is surely that what he terms the "Steig vs O'Donnell debate" played out in the open - and largely before the paper was published.

That means that arguments seeking to assert the validity of one conclusion or the other are being made long before the methods - which are key in assessing validity - have been thoroughly scrutinised.

Such rows make brilliant fodder for bloggers on "both sides of the debate"... and for the newish breed of journalists in mainstream media who've discovered that climate blogs make superb sources for stories, the entries requiring minimal adjustment in order to generate articles that appear ahead of the game and brim with righteous indignation - all without having to spend time reading peer-reviewed scientific papers.

So much febrile heat; so little light... and perhaps deliberately so - especially given that the O'Donnell paper did not disagree with the most important point from Steig's analysis, that warming had not been limited to the Antarctic Peninsula, but had affected the much more globally relevant West Antarctic region.

In the process, sophisticated analytical techniques have been dissected at length, which should mean we have better ones to work with next time - everyone wins.

So you might ask - what was all the fuss about?

There are certain issues where factions come together apparently seeking peace, reconciliation and a common way forward, when in reality at least one and possibly both profit from maintaining the status quo.

Climate change may be one; in which case, events like the one in Portugal are condemned to failure even before they begin.

And both episodes surely show more clearly than ever the need to separate the very different discplines of science and politics, in order that the factual conclusions of one can properly inform the choices of the other.


Whaling: Beginning of the end?

Richard Black | 12:36 UK time, Wednesday, 16 February 2011


Is this the beginning of the end for Japanese whaling in the Antarctic?

Clash between whaling ship and opponent

Clashes have been dramatic - enough to cause a U-turn?

That is the biggest question arising from Wednesday's announcement in Tokyo that this season's whaling programme was being suspended.

The Fisheries Agency (FAJ) hasn't formally declared the season over, but it appears likely that the fleet will soon be on its way out of the Southern Ocean and back to harbour.

FAJ official Tatsuya Nakaoku blamed the suspension on harrassment by the Sea Shepherd Conservation Society, which has made life progressively more difficult for the whaling fleet each year by sending faster and better-equipped boats.

This season, it has regularly managed to park across the back of the Nisshin Maru factory ship, making it impossible to winch whales on board.

Mr Nakaoku said it was a question of Sea Shepherd boats endangering safety.

So has Sea Shepherd won? It has pursued its campaign not only in face of physical opposition from the whaling fleet, but also objections from some anti-whaling observers who believe the annual confrontations handed the FAJ an opportunity to garner support by painting an image of anti-whaling activists as anti-Japanese and akin to terrorists.

The campaigns have certainly reduced the number of whales caught. The official target this season was 850 minke whales and 50 fin whales, although the fleet left port later than usual and was apparently aiming for a far smaller quota - perhaps as low as 200.

No official pronouncement has been made on the actual catch - Sea Shepherd estimates it at 30.

But the ocean skirmishes are just one part of a much bigger picture, with a number of factors combining to squeeze the Japanese whaling programme in a financial and political vice.

Whalemeat poster

Sales of whalemeat have fallen, despite promotion

The national budgetary situation is dire.

The Kyodo Senpaku company, which actually does the whaling on behalf of the Institute of Cetacean Research (ICR), is itself said to be in major financial difficulties.

The greater part of the funding for the whaling operation comes from selling meat.

With sales falling, and a constrained government not minded to raise its subsidy in compensation, a smaller fleet salied than in previous years - which made it more vulnerable to Sea Shepherd's attention.

(In fact, one of the ironies of the current situation is that the plucky anti-establishment activist group is probably much better funded than its state-backed foe - especially given its recent receipt of a million euros from the Dutch National Lottery.)

Sources from within the industry told Greenpeace in December that a smaller quota would be targeted this year, purely for financial reasons.

Meanwhile, the Australian legal case against Japanese whaling is due to come to the International Court of Justice this year.

It'll take several years to conclude and there's no guarantee Australia will win - even so, there may be some in the Japanese government who see the reputational damage as being just too severe.

Another looming constraint is that from next season, ships carrying heavy fuel oil will be banned from Antarctic waters under the International Maritime Organization's new anti-pollution code.

Switching the Nisshin Maru to diesel would be technically feasible - but would anyone foot the bill?

An alternative would be to invest in a new factory ship that would both meet the new pollution standard and be fast enough to escape Sea Shepherd's attention. 

But again - who's going to pay?

On the other hand - without such an upgrade, will the whaling fleet ever be effective again?

Reading the political runes is never easy on this issue, but there's no doubting that Mr Nakaoku's statement marks a major change of tone.

Flare on ship's deck

The ICR says activists have attacked with flares

Previously, the Fisheries Agency and the ICR have been adamant that Sea Shepherd would not win on the seas. Fire has been fought with fire, even to the extent of collisions that really did endanger lives.

Yet now the official line is that Sea Shepherd has made whaling impossible though compromising safety.

It is a remarkable turnaround - and it's matched by the apology that emerged late last year from the FAJ [video link], after it acknowledged that five of its officials had taken "free gifts" of whalemeat in substantial quantities.

Until that point, the official line had been to condemn Greenpeace, whose activists Junichi Sato and Toru Suzuki exposed the issue and were consequently put through criminal prosecution under threat of 10 years in prison (they eventually received suspended sentences).

So what it all means is, as yet, unclear.

But it looks increasingly the case that if the Japanese fleet is to go Antarctic whaling next season, it'll require substantial investment.

Negotiators at the heart of the "peace process" that fell apart at last year's International Whaling Commission (IWC) meeting believed Japan was looking for a way out of the Southern Ocean that saved face.

Admitting to defeat by Sea Shepherd doesn't feel like a face-saving solution.

Japan's whaling takes place under regulations permitting hunting for scientific research - technically it's the Japanese Whale Research Program under Special Permit in the Antarctic (JARPA-2).

There's due to be a review after the first six years of operation [pdf link] - which is after the end of the current season.

Might the review conclude that there's no need to continue the research?

Whatever the reality of such speculation - and speculation it is at this stage - it does at least appear possible that the current Antarctic hunting season will be the last.

On the other hand, the crisis might spur the whaling lobby in the Diet to action, and persuade the government that finding the necessary investment would be in the national interest. Maybe Japanese consumers will find a new taste for whalemeat, and the industry's economics will turn around.

Alternatively, the "national interest" card might be deployed in favour of ending the Antarctic operation and spending resources instead on increasing whaling close to shore.

Either way, the fleet's turn away from the Antarctic hunting grounds feels like a significant move in what has been a long-running war of attrition.


Palm oil deal points to corporate greening

Richard Black | 16:31 UK time, Wednesday, 9 February 2011


This week's announcement of a new partnership aimed at curbing deforestation in Indonesia should give succour to anyone who thinks consumers and companies, rather than governments, hold the key to curbing environmental decline.

Man with bike laden with palm oil fruits


Essentially, the world's second biggest (and Indonesia's biggest) producer of palm oil, Golden Agri-Resources (GAR), has joined forced with environmental group The Forest Trust (TFT) to establish and follow tougher rules on where they can plant.

Old-growth forest is supposed to be protected already - at least, where companies adhere to regulations established by the Roundtable on Sustainable Palm Oil (RSPO).

The new deal is principally aimed at preventing the release of carbon, and so will protect all forests whose tree density (and thus carbon storage) is above a certain threshold.

It will also ban development on peat. As Indonesia contributes about half of the world's CO2 emissions from peat, that's no trivial issue.

International organisations such as Greenpeace have been pursuing the East Asian palm oil industry for years (as they have the soy industry in the Amazon, for similar reasons).

Generate enough heat this way - persuade enough consumers to write angry letters to major brands or politicians, put companies' names in the press with unflattering references to their environmental footprint, maybe even instigate a boycott or two - and eventually, those major Western brands will pay attention.

Last year, TFT worked with Nestle [pdf link] to draw up rules ensuring the company's palm oil footprint, as it were, had no net impact on forests.

That meant Nestle putting pressure on its suppliers, creating problems for companies that did not up their game - and opportunities for those that did.

GAR's oil, for example, will now appear more attractive to a number of Western buyers - and at least some of GAR's competitors will presumably follow suit.

The deal comes at a paradoxical time for Indonesia.

In 2009, President Susilo Bambang Yudhoyono became one of the first developing country leaders to pledge control of greenhouse gas emissions, promising a curb of 26% by 2020 - or by 41% if enough international assistance were forthcoming.

That implies slamming the brakes on deforestation - the country's biggest source of emissions.

Last year, the government pledged a two-year moratorium on new logging concessions, in return for which Norway would contribute $1bn - a harbinger of the much greater wealth transfers that may come under the UN's Reducing Emissions from Deforestation and forest Degradation (REDD) scheme.

Palm plantation

Palm oil plantations create a monoculture - damaging to biodiversity, and more

But amid confusion over which of two decrees should be used to introduce the moratorium, the Indonesian government delayed implementation.

And last week it announced that most mining and logging companies in Kalimantan, the Indonesian province that takes up the largest slice of Borneo, were operating illegally.

This shouldn't exactly have been a surprise, given that organisations such as Global Witness, with local counterparts, have been researching and revealing such issues in southeast Asia for years.

The status of the Norway-Indonesia deal is currently unclear. But while it disentangles itself, TFT and its allies have taken a parallel route, scouting around the edges of government concerns and heading down the track of consumer and corporate engagement - and scored something of a success.

It's a tactic with a mixed record.

Probably the quintessential example of a success is the "dolphin-safe tuna" campaign of the 1980s, which saw consumers (especially in the US) demanding that retailers stock only fish caught using methods that did not harm dolphins.

The issue itself remains somewhat controversial, with critics maintaining the methods that fleets subsequently adopted have had a disproportionate impact on other marine species, less iconic but more threatened - while backers argue that rules established then have subsequently been watered down.

Whatever the rights and wrongs of that issue, there's little doubt that purely as a campaign, it was a huge success, sending ripples right through the industry.

But it's one of just a few successes in a huge industry - fisheries - that has remained largely barren.

Forestry, too, has not been substantially impacted by consumer and corporate pressure. As Greenpeace itself acknowledges, the Asian pulp and paper industry remains largely immune to outside influences, even as palm oil suppliers feel the consumer force.

And there are some regions of the world where the tradition of public engagement in such issues leading to corporate pressure just doesn't seem to have relevance - notably China, whose importance as a destination for all kinds of goods sourced in nature is soaring.

Nevertheless, the palm oil deal demonstrates that in certain circumstances, the tactic does work.

Ten years ago, Greenpeace and its counterparts were lambasting virtually the entire industry as unsustainable, socially exploitative and environmentally destructive. Now, they're suggesting that if GAR/TFT standards were applied across the whole sector, the war would virtually be over.

For some, then, this is a surely a day for a piece of celebratory cake - made, surely, with just a dash of sustainable palm oil.


Climate change: Contrary motion?

Richard Black | 13:56 UK time, Tuesday, 8 February 2011


Villager in Somalia with farm animals


One issue, two reports, two different conclusions.

In short, a recipe for confusion - at least, on the surface.

Last week the International Institute for Environment and Development (IIED), the London-based think-tank, published a report suggesting that fears of mass migration caused by climate change were misplaced.

A few days later, the Asian Development Bank (ADB) trailed its forthcoming report with a release recommending that:

"Governments in Asia and the Pacific need to prepare for a large increase in climate-induced migration in the coming years..."

At face value, then, the starkest of contradictions: and an important one, because if millions of people (perhaps a billion, according to a 2007 report from Christian Aid [pdf link]) are forced away from their homes, that's a huge issue for governments and international agencies to deal with.

If they're not, the money and resources that might have been mis-directed at this issue can be re-directed at others.

So why the confused picture? Is it really a confusion of conclusions - or of terminologies?

IIED has surveyed people's responses to threats such as drought in Bolivia, Senegal and Tanzania. Lead author Cecilia Tacoli summed up the conclusions like this:

"People affected by environmental degradation rarely moved across borders. Instead they moved to other rural areas or to local towns, often temporarily."

With the exception of people living in small island developing states threatened by sea level rise, IIED says fears of mass movements across national borders have been exaggerated.

But here's the ADB's early conclusion:

"In the past year alone, extreme weather in Malaysia, Pakistan, the People's Republic of China, the Philippines, and Sri Lanka has caused temporary or longer term dislocation of millions.

"This process is set to accelerate in coming decades as climate change leads to more extreme weather."

So when the ADB talks about migration, it doesn't mean across borders - it means within countries, and often short-term - precisely what IIED cites as the typical response.

The emotive one billion figure from Christian Aid also needs setting in context.

What it actually says is:

"We estimate that over the years between now and 2050, a total of one billion people will be displaced from their homes."

But 645 million of these would be displaced not by climate impacts, but by development projects such as dams and mines - the number comes simply through extrapolating the current rate, calculated at 15 million people per year.

Girl in Luanda

The IIED argues that developing country capitals should prepare for a population increase

A further 100 million come from other factors already familar - wars, extreme human rights abuse, and natural disasters.

So the figure relating to climate impacts is actually in the 250 million ballpark.

And that's spread over a period of 43 years - and the report doesn't specify that these migrants would travel internationally.

The IIED's main thrust (as outlined by Dr Tacoli in an article for our now defunct Green Room series of opinion articles back in 2009) is that migration shouldn't be seen as a problem, but as a natural adaptation and an opportunity:

"Policymakers must radically alter their views of migration, and see it as a vital adaptation to climate change rather than as an unwanted consequence or a failure to adapt.

"This means that poorer nations need to prepare for climate change at home by building up infrastructure and basic services in small towns located in rural areas that could become destination hubs for local migrants.

"Options include policies that promote access to non-farm jobs in small rural towns and a more decentralised distribution of economic opportunities"

And in the ADB's report, which at one stage looked like a direct contradiction, what's this we find?

"On the positive side, the report says that if properly managed, climate-induced migration could actually facilitate human adaptation, creating new opportunities for dislocated populations in less vulnerable environments."

So delve beneath the headlines, and the confusion disappears.

In many cases, effective climate adaptation will entail asking the question of whether it's better to help communities remain in situ, providing better facilities to help them survive floods, store water, keep animals, or whatever the issue may be - or whether the traditional lands are likely to become uninhabitable, in which case assisted migration might be considered a better option.

But the question will best answered locally.

And in any case, as many groups including IIED point out, many of the most vulnerable communities are among the poorest on the planet, which seriously constrains their options.

Whether the advice is along the lines of staying or going, increasing their wealth and therefore their options is surely the most fundamental of responses.


Oysters clear seas for local remedies

Richard Black | 11:43 UK time, Thursday, 3 February 2011


This week saw formal scientific publication of a report that produces one of the starkest conclusions I've seen about humanity's relationship with the oceans.


Globally, 85% of oyster beds have basically disappeared.

The paper, in the journal BioScience (though not apparently on its website yet), formalises results from a study conducted a few years ago co-ordinated by The Nature Conservancy (TNC), the US-based environment organisation.

The scientists behind the report (which we covered when TNC released the findings a couple of years ago) say this makes oyster beds "the most severely impacted marine habitat on the planet" - though researchers looking at the big ocean-going predators such as sharks, tuna and marlin might claim they're ahead in the race for this most undesirable of trophies.

In one sense it's not surprising. Oysters congregate in bays and estuaries - the easiest parts of the sea for humans to exploit.

From this, you might deduce that over-exploitation of oyster-beds (and indeed mussel-beds and other shellfish zones) isn't a new phenomenon; and you'd be right.

The Romans not only used oysters but farmed them [pdf link], constructing artificial beds along inhabited parts of the Italian coast.

Excavations in south-western France yielded piles of more than one trillion oyster shells; while in the late 1800s, the UK's oyster industry supported 120,000 workers - a far cry from today.

What happened next is a story all too familiar to anyone who's looked at the history of fisheries for more than a few seconds: we industrialised, mechanising the process of excavation.

In the New World, settlement in oyster-rich areas such as Chesapeake Bay increased demand for the shellfish many times over.


Oysters need a hard surface - in nature it is usually made from shells of other oysters

So fishermen increased the supply, until many of these grounds became shadows of their former glory.

Oysters need something hard to cling onto; a sea-floor of shifting sediment is no good to them.

What this means is fishing out an oyster reef basically means it won't come back.

Young oysters attach onto the shells of old ones, which are nice and hard.

When there are no shells left, there's nothing to cling onto, and even if there are any young around, they cannot survive.

Charles Clover, in that remarkable book The End of the Line, makes the case that parts of the North Sea owe their modern-day turbidity to the removal of beds that a century ago, were producing 100 times more oysters than today.

Oysters filter the water, clearing nutrients suspended in it; and the hardness of the bed means there's far less sediment stirred up by wave action.

"Nineteenth-century maps show oyster beds 200km (100 miles) in length on the Dutch and German side, but the last of these were fished out before the Second World War.

"Since then, there have been no oysters left to form a hard substrate across the bottom."

The implication is that if previous generations had looked after the resource better, present-day Britons (and Dutch and Germans) would not only have a much larger supply of oysters, we'd also have clearer waters for swimmers and divers to enjoy.

Without the luxury of being able to turn the clock back, two questions arise.

One is what can be done now to restore exhausted oyster beds.

The other is where the history of oyster overfishing should point us in terms of establishing regimes that protect and nurture valuable marine resources, so that our generation uses them sustainably and leaves some for the next.

Oyster restoration

Restoration projects in the Gulf of Mexico have successfully rebuilt some oyster reefs

The Nature Conservancy has pioneered the replenishment of defunct reefs and has a number of projects running, many in the Gulf of Mexico - although there, restoration has been compromised by defences deployed against the Deepwater Horizon oil leak.

Fresh water was allowed to flow in far greater quantities than usual into the sea in an attempt to push oil away from the shoreline.

But fresh water kills marine oysters; and TNC says millions have indeed been killed along the coast.

Nevertheless, it appears that where there's money and will, replenishment can be made to work.

On the longer-term question, we've recently had the UN biodiversity convention summit in Nagoya, Japan, and in just over a year we'll have the second Rio Earth Summit - both events concerned largely with the sustainability of biological resources.

In terms of ocean conservation, Nagoya wasn't a huge success, with nations pledging to slap protection orders on just 10% of the marine world - although other components of the agreement there should also help conservation, such as the move from "harmful" subsidies towards an economic regime that penalises destruction and encourages sustainable use.

With Rio+20, there's concern in some quarters that marine issues might be marginalised, given the attention now being focussed on the urban environment, forests, climate change, agriculture, food security, and such like.

There's no logical reason why that to happen - after all, climate change and food security are as relevant to the seas as they are to the land.

But the concern is there; and in an attempt to bring some attention to the issue, the Pew Environment Group recently launched a set of recommendations [pdf link] that went before delegates to the first preparatory conference in the process leading up to Rio+20.

Its top line:

 "With 70% of the Earth covered by the ocean, and given the importance of the ocean as the life support system of Planet Earth, now is the time for [the UN Commission on Sustainable Development] to pay due attention to the needs of the ocean, and to the hundreds of millions of people who depend on healthy ocean ecosystems for their very survival."

One of the approaches to marine management that is working well in some places, and that environment organisations support, is giving control to local communities, allowing them to manage their resource in association with scientific advice.

Logically, oysters should be a prime candidate for this kind of approach. They nestle in inshore waters where regulations can be easily enforced, and they're relatively high-value commodities, meaning that communities who manage the fishery properly are virtually guaranteed a long-term, stable source of revenue.

One of the problems with assessing the state of our environment is that it's easy to assume what we're used to is "natural".

That's why the kind of historical study TNC has just published is so valuable - to show us what we might never have suspected we were missing, and what we might rebuild given the resources, the knowledge and the will.

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