Friday 23 December 2016

O Come, All ye Fearful: 12 woes for Christmas future

This month I thought I would try and adopt something of the Yuletide spirit by offering something short and sharp (if not sweet) that bares a passing resemblance to the carol On the Twelve Days of Christmas. However, instead of gifts I'll be attempting to analyse twelve key concerns that humanity may face in the near future, some being more immediate - not to mention inevitable - than others.

I'll start off with the least probable issues then gradually work down to those most likely to have widespread effects during the next few decades. As it is meant to be a season of good cheer I'll even suggest a few solutions or mitigation strategies where these are applicable. The ultimate in low-carb gifts: what more could you ask for?

12: ET phones Earth. With the SETI Institute and Breakthrough Listen project leading efforts to pick up signals from alien civilisations, what are the chances that we might receive an extra-terrestrial broadcast in the near future? Although many people might deem this just so much science fiction, the contents of a translated message (or autonomous probe) could prove catastrophic. Whether it would spark faith-based wars or aid the development of advanced technology we couldn't control - or be morally fit enough to utilise - there may be as many negative issues as positive ones.

Solution: Keeping such information secret, especially the raw signal data, would be incredibly difficult. Whether an international translation project could be conducted in secret is another matter, with censorship allowing a regular trickle of the less controversial information into the public domain. Whilst this is the antithesis of good scientific practice, it could prove to be the best solution in the long term. Not that most politicians are ever able to see anything that way, however!

11. Acts of God. There is a multitude of naturally-occurring events that are outside of human control, both terrestrial (e.g. super volcano, tsunami) and extra-terrestrial, such as asteroid impacts. Again, until recently few people took much interest in the latter, although Hollywood generated some awareness via several rather poor movies in the late 1990s. The Chelyabinsk meteor of February 2013 (rather than meteorite, as most of the material exploded at altitude led to 1500 injuries, showing that even a small object that doesn't reach the ground intact can cause havoc. Since 2000, there have been over twenty asteroid impacts or atmospheric break-ups ranging from a kiloton up to half a megaton.

Solution: Although there are various projects to assess the orbits of near-Earth objects (NEOs), the development of technologies to deflect or destroy impactors requires much greater funding than is currently in place. Options range from devices that use just their velocity to knock NEOs off-course to the brute force approach of high-powered lasers and hydrogen bombs. However, with the cancellation of NASA's Ares V heavy launch vehicle it's difficult to see how such solutions could be delivered in time. Hopefully in the event something would be cobbled together pretty quickly!

10. Grey goo scenario. As defined by Eric Drexler in his 1986 book Engines of Creation, what if self-replicating nanobots (developed for example, for medical purposes), break their programming and escape into the world, eating everything in their path? Similar to locust swarms, they would only be limited by the availability of raw materials.

Solution: The Royal Society's 2004 report on nanoscience declared that the possibility of von Neumann machines are some decades away and therefore of little concern to regulators. Since then, other research has suggested there should be limited need to develop such machines anyway. So that's good to know!

9. Silicon-destroying lifeforms. What if natural mutations lead to biological organisms that can seriously damage integrated circuitry? A motherboard-eating microbe would be devastating, especially in the transport and medical sectors, never mind the resulting communication network outages and financial chaos. This might sound as ridiculous as any low-grade science fiction plot, but in 1975 nylon-eating bacteria were discovered. Since then, research into the most efficient methods to recover metals from waste electronics have led to experiments in bioleaching. As well as bacteria, the fungus Aspergillus niger has been shown to breakdown the metals used in circuits.

Solution: As bioleaching is potentially cheaper and less environmentally damaging it could become widespread. Therefore it will be up to the process developers to control their creations. Fingers crossed, then!

8. NCB. Conventional weapons may be more common place, but the development of nuclear, chemical and biological weapons by rogue states and terrorist organisations is definitely something to be worried about. The International Atomic Energy Agency has a difficult time keeping track of all the radioactive material that is stolen or goes missing each year.  As the 1995 fatal release of the nerve agent sarin on the Tokyo subway shows, terrorists are not unwilling to use weapons of mass destruction on the general public.

Solution: There's not much I can suggest here. Let's hope that the intelligence services can keep all the Dr Evils at bay.

7. Jurassic Park for real. At Harvard last year a chicken embryo's genes were tweaked in such a way as to create a distinctly dinosaurian snout rather than a beak. Although it may be sometime before pseudo-velociraptors are prowling (high-fenced) reserves, what if genome engineering was used to develop Homo superior? A 2014 paper from Michigan State University suggests both intellectual and physical improvements via CRISPR-cas9 technology is just around the corner.

Solution: If the tabloids are to be believed (as if) China will soon be editing human genomes, to fix genetic diseases as well as generating enhanced humans. Short of war, what's to stop them?

Planet Earth wrapped as a Christmas present

6. DIY weaponry. The explosion in 3D printers for the domestic market means that you can now make your own handguns. Although current designs wear out after a few firings, bullets are also being developed that will work without limiting their lifespan. Since many nations have far more stringent gun laws than the USA, an increase in weaponry among the general public is just what we don't need.

Solution: how about smart locking systems on printers so they cannot produce components that could be used to build a weapon? Alternatively, there are now 3D printer models that can manufacture prototype bulletproof clothing. Not that I'd deem that a perfect solution!

5. Chemical catastrophe. There are plenty of chemicals no longer in production that might affect humanity or our agriculture. These range from the legacy effects of polychlorinated biphenyl (PCB), a known carcinogen, to the ozone depletion causing by CFCs, which could be hanging around the stratosphere for another century; this doesn't just result in increased human skin cancer - crops are also affected by the increased UVB.

Solution: we can only hope that current chemical development now has more rigorous testing and government regulation than that accorded to PCBs, CFCs, DDTs, et al. Let's hope all that health and safety legislation pays off.

4. The energy crisis. Apart from the obvious environmental issues around fossil fuels, the use of fracking generates a whole host of problems on its own, such as the release of methane and contamination of groundwater by toxic chemicals, including radioactive materials.

Solution: more funding is required for alternatives, especially nuclear fusion (a notoriously expensive area to research). Iceland generated 100% of its electricity from renewables whilst Portugal managed 4 consecutive days in May this year via wind, hydro, biomass and solar energy sources. Greater recycling and more incentives for buying electric and hybrid vehicles wouldn't hurt either!

3. Forced migration. The rise in sea levels due to melt water means that it won't just be Venice and small Pacific nations that are likely to become submerged by the end of the century. Predictions vary widely, but all in the same direction: even an increase of 150mm would be likely to affect over ten million people in the USA alone, with probably five times that number in China facing similar issues.

Solution: a reduction in greenhouse gas emissions would seem to be the thing. This requires more electric vehicles and less methane-generating livestock. Arnold Schwarzenegger's non-fossil fuel Hummers and ‘Less meat, less heat, more life' campaign would appear to be good promotion for the shape of things to come - if he can be that progressive, there's hope for everyone. Then of course there's the potential for far more insect-based foodstuffs.

2. Food and water. A regional change in temperature of only a few degrees can seriously affect crop production and the amount of water used by agriculture. Over 700 million people are already without clean water, with shortages affecting agriculture even in developed regions - Australia and California spring to mind. Apparently, it takes a thousand litres of water to generate a single litre of milk!

Solution: A few far-sighted Australian farmers are among those developing methods to minimise water usage, including a few low-tech schemes that could be implemented anywhere. However, really obvious solutions would be to reduce the human population and eat food that requires less water. Again, bug farming seems a sensible idea.

1. Preventing vegegeddon. A former professor at Oxford University told me that some of his undergraduates have problems relating directly to others, having grown up in an environment with commonplace communication via electronic interfaces. If that's the problem facing the intellectual elite, what hope for the rest of our species? Physical problems such as poor eyesight are just the tip of the iceberg: the human race is in severe danger of degenerating into low-attention ‘sheeple' (as they say on Twitter). Children are losing touch with the real world, being enticed into virtual environments that on the surface are so much more appealing. Without knowledge or experience of reality, even stable democracies are in danger of being ruled by opportunistic megalomaniacs, possibly in orange wigs.

Solution: Richard Louv, author of  Last Child in the Woods: Saving Our Children From Nature-Deficit Disorder suggests children require unstructured time out of doors in order to gain an (occasionally painful) understanding of  the real world; tree-climbing, fossicking, etc. Restricting time on electronic devices would seem to go hand in hand with this.

Well, that about wraps it up from me. And if the above seems somewhat scary, then why not do something about it: wouldn't working for a better future be the best Christmas present anyone could ever give?

Thursday 24 November 2016

Unwanted aliens: is a predator-free New Zealand realistic by 2050?

In a moment of half-baked madness worthy of Donald Trump, the New Zealand Government has announced a plan to make the nation predator-free by 2050. As can be imagined this statement has attracted a wide range of opinions, even from across various conservation groups. These vary from the extremely optimistic viewpoint of Forest and Bird advocacy manager Kevin Hackwell, who claims it is achievable even earlier, to the Green Party's conservation spokesman Kevin Hague, who publicised a University of Auckland study estimating the project's budget at an astonishing if not untenable NZ$9 billion.

With the government prepared to provide just one-third of the plan's funding, it's difficult to imagine which private sector companies would be willing to supply the lion's share over the next three decades. As expected, the response of New Zealand's political opposition has been to pour very cold water on the plan, including the claim that no nation has ever managed to wipe out its population of rats (Hamelin and its Pied Piper notwithstanding).

One of the most essential questions is what is defined as a pest in the context of this proposal?  The relevant Department of Conservation (DoC) page names three principle animal pests: possums, rats and stoats, with a further page expanding the list to other introduced animals and freshwater fish, including cats and dogs (both domestic and feral). Some of the species listed were deliberate introductions, mainly in the Nineteenth Century, whilst others came in accidentally under the radar - New Zealand's biosecurity protocols not always being as draconian as they are now.

A few statistics offer a frightening idea of the scale required: as of 2001 it was estimated that there were seventy million possums in New Zealand, eating 21,000 tonnes of vegetation every night. Needless to say, much of this material consists of endemic species such as pohutukawa and southern rata trees. This then has a knock-on effect for the native fauna that feeds or nests on these species, which of course is in addition to being direct prey for the possum.

Although cats and dogs might be thought of more as pets than pests, even in low numbers they can be devastating to native wildlife. A classic example is the extinction of the Stephens Island wren thanks to a number of feral cats, whilst it is thought that one stray dog managed to kill more than five hundred large brown kiwi in the Waitangi State Forest in less than a year.

DoC's Battle for our Birds scheme relies on aerial drops of poison and ground baits/traps to eradicate the key non-native pests. This year their target area was almost 900,000 hectares; to give an indication of the increase in scale necessary for a nationwide eradication, New Zealand is close to 27 million hectares in total. Perhaps the much-misused term 'paradigm shift' could be safely applied in this circumstance?

At this point it should be mentioned that there are varied opinions as to what the government's planned outcome is. After all, there have been humans living in New Zealand for over seven centuries, so there is little chance of any except the most remote locales returning to a pristine ‘natural' wilderness, even if we knew exactly what that meant. Having said that, the Pleistocene Park project in Russia is attempting something along similar lines. A small region of north Siberian tundra is being converted into glacial period steppe, using musk ox and other large animals as surrogates for extinct mega fauna such as mammoth and woolly rhinoceros. The resulting flora appears to be much more diverse and interesting than the unmanaged wilderness surrounding it, which is ironically the antithesis of what one would expect or hope for with untouched versus deliberately altered landscapes!

Then there's the scale issue: whilst possums, rats and mustelids are relatively easy to track and observe, small species such as wasps and argentine ants are far more difficult to locate, never mind eradicate. Although they don't inflict as much obvious damage to the native flora and fauna, they can nonetheless cause fundamental changes to the ecosystem. Wasps for example eat honeydew, which is an important food source for lizards and native birds such as kaka.

It isn't just insects that would be tricky to wipe out. The rainbow or ‘plague' skink was accidentally introduced from Australia about half a century ago and now seems ubiquitous in Auckland; I've seen it everywhere from volcanos to paddocks, gardens to garages, even inside a bookshop. Thanks to much faster reproduction and maturation rates than native equivalents, it appears to be rapidly out-competing them.



One issue that prevents a complete turning back of the clock is the extinction of dozens of species since the arrival of humans in the country. How can the ecosystem, especially food webs, maintain a long-term balance with key species missing? No-one is suggesting we bring in cassowaries to replace the nine species of moa. Of course, being large creatures they were probably none too numerous, yet there is an hypothesis that they may have been involved in an evolutionary arms race with lancewood, the juvenile trees being well-protected against moa browsing them.

Therefore any attempt to preserve a largely native ecosystem will need to ensure the food webs are fully-functional, with plenty of indigenous pollinators such as short-tailed bats and kereru (native pigeon). Key native species need to identified and preserved just as much as introduced ones removed. This in turn begs the obvious point that since evolution is an ongoing process, are we attempting to freeze the environment at a particular snapshot in time rather than allowing nature to take its course? Even accounting for punctuated equilibrium, natural selection hasn't suddenly stopped in New Zealand any more than it has elsewhere.

The pest-free project will presumably need to tackle species in a certain order, since if mustelids and feral cats are eliminated then rats will proliferate, whilst without rats as prey, the former species will be forced to look for alternative food sources instead; doubtless native birds would form the mainstay of this.

As I have discussed elsewhere, it shouldn't just be the enemies of the native poster species that are targeted. There are plenty of critters less famous than parrot kakapo and ancient reptile tuatara that deserve some attention too, with the endemic weta an obvious example (over twenty percent of its species are currently under threat). Invertebrates play an almost unknown role in nutrient recycling and waste disposal, as well as appearing on the menu of more conspicuous animals. Considering that the takahe, the largest species of swamp hen, was thought extinct for half a century, perhaps we shouldn't be surprised about how little is known concerning the size and condition of native creepy crawly populations. However small and insignificant we might judge them, we ignore their loss at our peril.

Also often overlooked are the native freshwater creatures. Competition comes in the form of the high number of invasive species that compete or predate on them. A key example is the aggressive gambusia, a Mexican fish introduced to eat all the mosquito larvae - which of course it fails to do. Interestingly enough, the DoC website excludes some introduced species from its list of pests: salmon and trout for example are categorised as 'sports fish'. Therefore is economics the government's primary motive for the pest eradication plan, rather than good old-fashioned conservation for the sake of it? After all, the extremely rare takahe was once given second place to herds of elk that had been introduced to serve as a big game animal.

There may be something in this. Mainstream politicians are renowned for their lip service commitment to environmental issues. Could it be that in the wake of the highly negative stories earlier this year concerning exceeded fishing quotas and river pollution, the government is fighting to redeem New Zealand's '100% Pure' brand image?  In addition, agriculture might benefit from an increase in native species' populations. An outstanding example of the latter is shown by a Federated Farmers of NZ estimate that native bees provide pollination services to the tune of NZ$4.5 billion per year!

Finally, we get to flora. As Bec Stanley, a curator at Auckland's Botanic Gardens, is keen to point out, the majority of people have plant blindness compared to their interest in animals. There are thought to around three invasive plant species for every four natives, with old man's beard, gorse, ragwort and nightshade being amongst the best-known culprits. These can smother and kill native plants, thus depriving indigenous animals of food. Despite being vital to the ecosystem, the war on introduced vegetation really seems to be underdeveloped compared to that against non-native animals.

It doesn't take much to upset the balance of at least a local-scale environment. The surviving remnants of mighty kauri forest are currently facing a disease thought to be caused by an introduced water-mould pathogen, a clear case of David conquering Goliath. Without careful consideration, the project to rid New Zealand of introduced pest species could end up doing more harm than good. The motives are potentially dubious and the research chronically under-funded. It remains to be seen whether there is the willpower to see it through or if it is just one more piece of political rhetoric that evaporates by the next election. Personally, I'm in favour of the idea, but uncertain of how realistic it is. Regardless, the citizens of New Zealand need to do their best, lest many more species join the ranks of moa, huia, adzebill and many, many others. After all, who wants their children living in an environment dominated by feral pigeons, rats and possum?

Thursday 27 October 2016

Murky waters: why is the aquatic ape hypothesis so popular?


Whilst not in the same class as the laughably abysmal Discovery Channel mockumentaries on the likes of mermaids and extant (rather than extinct) megalodon, the recent two-part David Attenborough BBC Radio 4 documentary The Waterside Ape has left me gritting my teeth...grrr.

The programme has confirmed something I suspected from his 2010 BBC television series and associated book, First Life: namely, that the style of his exposition takes priority over the substance of his material. I'll quickly recap on the howler he made in an episode of First Life, ironically one that featured renowned trilobite expert Richard Fortey, albeit in a different sequence. When discussing trilobites, Sir David briefly mentions that they get their name from having three segments from front to rear: head, body and pygidium (tail) - which is totally wrong!

The name is the give-away. Tri-lobe refers to the three segments across the width of the body: a central lobe and two lateral lobes. Many creatures have the head, body and tail segmentation, so it would be far from unique in trilobites. I find this example of incorrect information rather discomforting, especially from someone like Sir David who has been a fan of trilobites since childhood. You have to wonder why experts aren't invited to give BBC science and nature documentaries the once-over before broadcast, just in case any gaffes have got through to the final cut?

The issue then, is that if we non-professionals believe the content espoused by such senior figures in the field of science communication - and if such material goes without basic error-checking from professionals - how is the public to receive a half-decent science education? Of course science isn't a body of knowledge but a toolkit of investigation techniques, but few of the general public have the ability to test hypotheses themselves or access the jargon-filled original scientific papers. So relying on books and media from distinguished communicators is the primary way of increasing our STEM (Science, Technology, Engineering and Mathematics) knowledge.

Back to The Waterside Ape. The hypothesis is an old one, dating back to marine biologist - and let's face it, oddball theorist - Sir Alister Hardy's first, unpublished speculations in 1930. However, the idea didn't achieve widespread dissemination until Elaine Morgan began to publicise it in the early 1970's. Otherwise known as a fiction writer, Morgan's output on the aquatic ape hypothesis was originally considered to be a feminist critique rather than particularly serious science, bearing in mind that the author lacks professional training or experience in the field of evolutionary biology.

Whether it is thanks to dissemination via the World Wide Web, her pro-aquatic ape books have become ever more popular over the past twenty years. This is in spite of the ever-increasing number of hominin fossils and sophisticated analytical techniques that have shown little support for the idea. I'm not going to examine the evidence for and against the hypothesis, since that has been done by many others and I'm marginally less qualified to assess it than Elaine Morgan. Instead, I'm more interested in how and why the idea has maintained popular appeal when the general consensus among the specialists is that it is profoundly incorrect.

Could it be that the engaging quality of Morgan's writing obscures a lack of dry (geddit?) analysis upon a subject that could at best be deemed as controversial - and thus fool the general readership as to its validity? Or is there more to it than that? The BBC seem to have maintained an on-going interest in supporting her work over the past two decades.

Indeed, The Waterside Ape is not David Attenborough's first foray into the idea. He made another two-part BBC Radio 4 series called Scars of Evolution back in 2005, which included some of the same interviews as the recent programmes. The BBC and Discovery Channel also collaborated in 1998 on a television documentary favouring the hypothesis called surprisingly enough The Aquatic Ape, albeit without Attenborough's involvement.

A key argument that I'm sure gets public support is that the of a radical - and female - outsider being shunned by the conservative, male-dominated establishment, with Elaine Morgan pitted against the reactionary old guard of palaeontologists, biologists, etc. Her plight has been described in the same vein as meteorologist Alfred Wegener's battle with orthodox geology between the world wars, but in Wegener's case his hypothesis of continental drift lacked a mechanism until plate tectonics was formulated several decades later. As for the aquatic ape, there seems to be a suite of models describing a gamut of ideas, from the uncontroversial speculation of hominins wading for iodine- and Omega-3-rich foodstuffs (promoting brain growth) to human ancestors being Olympic-class ocean swimmers who would feel at home in a Discovery Channel mermaid mockumentary.

We shouldn't ignore the emotive aspects of the hypothesis, which the various programmes have described as a "fascinating idea" that would be "lovely to confirm". Since most people still think of dolphins as innocent, life-saving and cute (when in fact they play brutal cat-and-mouse games with live porpoises) could this be a psychological attempt to salvage something of our own rapacious species?

Elaine Morgan admitted that her first book was a response to her annoyance with the 'killer ape' theories of the 1960's, as espoused in Robert Ardrey's seminal 1961 volume African Genesis. In these post-modern, politically-correct times of gatherers first and hunters second, Raymond Dart and Robert Ardrey's once-influential machismo ape-man has fallen from favour. Unfortunately, the famous Ardrey-influenced Dawn of Man sequence in 2001: A Space Odyssey promotes just such a viewpoint, so perhaps it isn't any wonder that supporting a more tranquil aquatic ancestry might appear to be an easy way to bring 21st century sensitivities to a world reeling from constant violence.

Another possible reason for the hypothesis' widespread support is that it relies on what appears to be an impressive accumulation of facts in the Darwinian mould, without recourse to difficult mathematics or sophisticated technical jargon. For those unable to get a clear understanding of major contemporary science (Higgs boson, anyone?) the idea of aquatic ape ancestors is both romantic and easy to digest, if the supporting evidence is taken en masse and the individual alternatives for each biological feature ignored or undeclared.

Clearly, whoever thinks that science is detached from emotion should think again when considering the aquatic/waterside/paddle-boarding ape. Although on the surface a seductive idea, the collection of proofs are selective, inadequate and in some cases just plain wrong. It might be good enough for the sloppy pseudo-scientific archaeology of Graham Hancock and Erich von Daniken, but good science needs rather more to go on. Yes, there are some intriguing nuggets, but as Dr Alice Roberts said in her critique of the recent Attenborough radio series, science is about evidence, not wishful thinking. Unfortunately, the plethora of material contains rather more subtleties than trilobite nomenclature, so I can only sigh again at just how many equally poorly-concocted ideas may be swashing around the world of popular science communication. Come on, Sir David, please read past the romance and dig a bit deeper: the world needs people like you!

Monday 26 September 2016

Mopping up spilt milk: pollution in the New Zealand dairy sector

It's been slow to dawn on New Zealanders, but for a country that prides itself on a '100% Pure' image our environmental pollution record is fairly appalling - and shows few signs of alleviation. Politicians who point to the large percentage of the nation's electricity generation coming from renewable sources, not to mention the slow but sturdy growth in hybrid vehicles, are completely missing the point: it has been claimed that over half of New Zealand's greenhouse gas emissions emanate from agri business.

Although the quantity of sheep in the country has plummeted from a 1982 peak of around 70 million to less than 30 million last year, cattle numbers continue to rise. There are about 3.6 million livestock on beef farms and circa 6.5 million dairy cattle. The latter sector generates twenty percent of New Zealand's exports and seven percent of its GDP, so it forms a substantial component of the kiwi economy. But with plans to double the country's dairy production by 2025, the term 'sustainable development' appears to be, well, unsustainable.

Since cattle create as much waste product as fourteen humans, it's not difficult to imagine some of the more obvious forms of dairy pollutant, smell and all. As New Zealand dung beetles are primarily forest dwellers there have been trials of introduced dung beetle species to help clean up the waste, with a reduction in nitrous oxide emissions from the soil and a lowering of cattle disease as side benefits. However, pastoral poo is only one element in the catalogue of pollutants caused by dairy farming.

Last summer I was taken to an outdoor swimming hole not far from Wanganui, consisting of a rectangular concrete-lined pool situated on the edge of a forest. I was informed that children had swam there until a decade or so, but no more: several signs warned that the water is contaminated and no longer safe for humans. This story has been repeated throughout New Zealand, with agriculture being by far the most common culprit. It isn't just artificial environments that have this problem; reports suggest that within the past twenty years about two-thirds of monitored swimming areas within rivers have become too polluted. And that's just for people; there's far less concern for the effects on river fauna and flora.

Although environmentalists have been issuing warnings for years, not enough has been done to alleviate this problem. Last month approximately five thousand inhabitants of Havelock North were taken ill due to tap water contaminated by campylobacter. The source was a series of bores which the director of the Infectious Diseases Research Centre at Massey University, Professor Nigel French, put down to pollution from sheep and cattle. Sources of contamination could include carcases of dead livestock, as well as faecal matter getting into waterways that provide the source of unchlorinated - and therefore at risk - tap water.

In fact, the outbreak appears to be the tip of the iceberg. Despite some hundreds of cases of illegal effluent discharge brought against New Zealand farmers each year, many more escape prosecution. It has to be said this seems to be a regular occurrence for the Ministry for Primary Industries, judging by the recent reports of their waiving prosecutions for commercial fishing vessels caught flouting bycatch and dumping laws. Turning a blind eye seems to be the order of the day when it comes to protecting food production - or at least the food producers. This philosophy seems to be driven by those who clearly have little understanding of the complexity - and at times fragility - of food webs. Not so much short-term thinking as profound myopia!

In addition to the organic matter there are chemical pollutants that can find their way into water supplies situated close to farms. Since the 1990s, the New Zealand Ministry for the Environment has been monitoring ground water for nitrates and has found levels substantially above those recommended for drinking water. Although chemical fertiliser has been blamed in addition to livestock effluent, environmental mapping suggests the latter is the primary cause, since the polluted areas heavily coincide with the widest-scale dairy production.

As well as polluting waterways dairy farmers have also been caught stealing billions of litres of water each year from rivers and aquifers, especially in the Canterbury region. Whilst not a form of pollution per se, this is obviously somewhat lacking in the environmentally-friendly stakes. The deforestation of low-lying plains for cattle grazing is also a source of pollution, as the lack of tree roots, besides allowing greater flooding, can generate increased run-off into rivers. This polluted water can lead to algal blooms, lowering oxygen levels and so endangering freshwater fish. That might not sound of any great concern except to diehard anglers, but for any whitebait fans, four of the five Galaxiidae species whose young form this delicacy are now said to be threatened.

The systematic destruction of forests to make way for pastoral land use has been repeatedly raised as a concern not just by environmental organisations but by the New Zealand Ministry of Agriculture and Forestry (MAF) itself. Their 2006 report claimed close to half a million hectares of the nation's forests were at risk of conversion to land for cattle grazing.

In addition, overseas forests are also affected: since 2008 the amount of palm kernels imported into New Zealand as a dairy cattle feed supplement has doubled to over 2 million tons per annum. This accounts for about twenty-five percent of global production and comes at the expense of destruction of rainforests in nations including Indonesia and Malaysia. Although the state-owned farm company Landcorp Farming Ltd is in the process of moving to a different supplement over the next year or so, the dairy giant Fonterra has not announced similar intentions. What's wrong with those guys: a surfeit of Milton Friedman in their formative years?

Having covered solids and liquids, it's time to move on to gas. As I've mentioned on various occasions, methane is a primary greenhouse gas. It was therefore shocking to discover that per capita, New Zealand has the greatest annual methane emission rate worldwide, accounting for over forty percent of the country's greenhouse gas emanations. The methane emission from dairy cattle alone has continually increased over the past quarter century, although the amount reported varies from ten percent to a whopping fifty percent or so. Perhaps that's not surprising, considering cattle can each generate up to 500 litres of methane per day!

There is some recent cause for hope, with various trials under way to reduce bovine emissions. These range from vaccination to selective breeding to diets bases on forage rape, with the latter showing that the change in feed affects fermentation - and therefore reduces methane production - in sheep. However, it wouldn't hurt to see the Government funding more research in this matter: one widely-reported paper last year was Massey University's The New Zealand Dairy Farming: Milking Our Environment for All its Worth, which received much criticism from the dairy sector when it was revealed to consist primarily of a student thesis.

It's very easy to become depressed with such deleterious effects coming from just one sector. Of course no nation can afford to rest on its laurels: we cannot turn the clock back. The halcyon image of bucolic ruralism is a myth perpetrated by those who have never worked on the land and farmers deserve the benefits of modern technology in their work as much as anyone. The development of sophisticated tools and software can aid the dairy sector in preserving the environment. as long as there is enough public money to support this eco-friendly research. But Government funding for this type of sustainable development appears to be sadly lacking. Doesn't it make sense that those who run God's Own Country should try a little harder to prove that the 100% Pure tagline isn't just marketing spin?