Snipe-hunting on subantarctic Campbell Island
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Over the last few years, several worthwhile scientific/ biological discoveries have been made at the Chatham Islands. While these finds may shape the future of conservation and research efforts, they also serve as a vivid reminder that there are still a lot of rocks left to be turned—and not just on the Chathams…
The world’s thirst for transport fuels shows no sign of slackening anytime soon. Indeed, with affluence rising across much of Asia and Eastern Europe, vehicle numbers are steadily increasing. Almost all the demand for fuel is met from petrol and diesel refined from crude oil, a fossil fuel. Burning fossil fuels releases carbon into the atmosphere, where carbon dioxide levels are steadily rising and, in the opinion of many, contributing to global warming. At the same time, oil reserves are becoming depleted and political instabilities in several major oil-producing countries are exacerbating supply worries, leading to escalating prices. Many countries around the world, including New Zealand, are looking to reduce their dependence on foreign oil supplies both to increase energy security and to reduce the burgeoning economic strain of paying for all that expensive imported oil. Further oil discoveries in New Zealand would offset the cost of importing oil, but would not reduce the price motorists pay at the pump nor ameliorate the carbon dioxide problem. (An average vehicle is estimated to emit 53,000 kg of carbon dioxide over its lifetime). In 1994, Jim Watson, a biology professor from Auckland University, founded New Zealand’s first biotechnology company, Genesis Research and Development Ltd. The company’s latest interest is in developing economic biofuels that could be produced locally to replace imported petroleum. After considerable investigation, it has determined that ethanol is an acceptable replacement fuel for petrol and willows belonging to the genus Salix have clear advantages as a raw material for producing biofuels. In conjunction with The Lake Taupo Development Company, Genesis is setting up BioJoule Technologies Limited to manufacture ethanol and other products from plantations of special willow cultivars they are establishing in the Taupo district. What makes ethanol—an alcohol identical to that present in wine and beer—a potentially good fuel for vehicles? Unlike hydrogen or natural gas, ethanol is a liquid at normal temperatures, however it is less volatile than petrol so would require a cold starting system at temperatures below 13º C. Compared with petrol, it is higher in octane rating, but has only 66 percent of the overall energy content. This means many engines need modification to run on ethanol, including larger carburettor jets, higher compression, and altered spark timing. Ethanol also damages a range of plastics and rubbers commonly used in petrol-fuelled vehicles, but none of these difficulties are major. It is miscible with water, so washing away spilt fuel is easy, but it also forms a very stable mixture with 4 percent water, meaning it cannot be distilled to give 100 percent pure ethanol. Again, this is a nuisance but not an insuperable problem as molecular sieve technology can dehydrate the ethanol for blending with petrol. Ethanol is cleaner-burning than petrol in terms of some pollutants produced, although it releases a similar amount of carbon dioxide. However—and this is the big thing—if the ethanol has been made from plant matter, the carbon dioxide is not adding to the atmosphere’s pool, merely turning over carbon a plant earlier captured from the air as it carried out photosynthesis. Although much ethanol at present is made from oil, it can be readily produced from plants. Enzymes present in yeast easily convert plant sugars to ethanol, although simultaneously releasing carbon dioxide. But plants—including trees—always contain much cellulose, a very stable polymer of glucose. Although it cannot be converted directly to ethanol, microbes (but not animals) possess cellulose enzymes which break it down into glucose, and glucose can be readily fermented into ethanol. It is the economic conversion of cellulose to ethanol that is the holy grail with ethanol, and rising petrol prices are making it feasible. Not many plants have a lot of free sugar waiting to be turned into ethanol, and those that do (eg sugarcane) have competing demands for that sugar. But every plant is rich in cellulose and it is not currently used when crops are harvested. Cellulose is also available elsewhere. Waste paper is mostly cellulose and sewage contains a goodly amount of the stuff as well. Another advantage of ethanol as a fuel is that it can be introduced to the market gradually. As long as ethanol is free of water, it can be mixed with petrol in any proportion. Engines burning low percentages of ethanol (eg 10 percent ethanol, 90 percent petrol, E10) require no modifications at all. In Brazil, sugarcane waste is used to make ethanol and cars run on petrol containing 22 percent ethanol. Some vehicles are now being manufactured that can run on either petrol or pure ethanol or any mixture of the two. BioJoule began a 2 ha trial of Salix cultivars in September 2004 on land provided by a Tuwharetoa farm trust and a second, much larger series of trials was initiated in September 2005 on 6.6 ha. On three separate sites, the performance of up to seven different Salix cultivars planted at a density of 12,000 stakes per ha has been compared together with such things as fertilizer trials, land preparation methods and weed management regimes. A third series of trials are planned for setting out in July, 2006 on a further 2.3 ha of land with 24,000 more plants. High biomass yield is the most important trait for a bio-energy crop. Salix has been chosen because of its rapid growth rate in a wide range of climatic and soil conditions. It can produce up to 16 tonnes of dry matter per hectare per year without the addition of nitrogen fertiliser. Conventional plant breeding has been used to enhance biomass productivity and significant yield gains have been achieved by crossing Asian Salix clones with European clones. Further gains through breeding programmes are assured. But why use Salix at all? Why not Pinus radiata or maize? Hardwood trees offer certain advantages over other plants. Some of them, including Salix, coppice— sprout again from the roots after felling. The existence of a large established root system means that trunks regrow much faster than those of newly-planted trees. However, grasses also regrow once mown, and some biofuel feedstock options involving use of switchgrass are being promoted in the US. Grass contains much less lignin than trees. It is worth noting that wood and plant cell walls are composed of three main materials—a core of cellulose (50 per cent of the dry matter) wrapped in protective layers of hemicellulose and lignin (each about 20 to 30 per cent). While cellulose can be broken down into glucose and fermented to ethanol, the sugars that make up hemicellulose (mainly xylose) are not so easily turned into ethanol. Lignin is not sugar at all but a complex of polyphenols. In hardwoods, the lignin is mostly in the S form which is more amenable to processing than the G form found in softwoods. Lignin and hemicellulose must be removed before the cellulose can be processed. Most companies interested in obtaining ethanol from cellulose regard lignin and hemicellulose as obstacles. At best, they burn lignin to provide energy for processing. BioJoule sees things differently. It intends to salvage the xylose from hemicellulose and the lignin. Xylose, processed to xylitol, is a sweetener like sucrose, but does not promote either diabetes or tooth decay. Lignin can be used in place of oil products, as a source of raw materials for making paints, resins, plastic films, adhesives and more. Low temperature pyrolysis of lignin yields such basic organic chemical feedstocks as toluene, ethylene and propylene. Hence Biojoule plans multiple income streams from its wood processing— willow stake sales, ethanol, xylose and lignin—and hopefully more. It is for this reason, total biomass refining to multiple products, that makes Salix such an attractive material. So far the company has made Salix selections and determined how it will process the wood, using its scientific and engineering resources and laboratory-scale experiments. The next step is to construct a pilot plant that can process up to 1000 kg of dry matter a day. The processing of woody biomass from corn and forest trees to produce bioethanol has been investigated for more than 30 years worldwide. Current technologies use a variety of high pressure chemical processing systems to disrupt the structure of the wood to remove lignin. These processes expose the cellulose for enzymatic degradation to sugars. BioJoule have evaluated, at laboratory-scale, the operation of the out-of-patent Organosolv process and have shown that this process efficiently separates lignin from Salix cellulose. Incidentally, using pine, a softwood, the process does not work nearly as well. It involves treating willow chips with 50–70 per cent ethanol at high temperature and pressure in a digestor designed by BioJoule. In contrast to lignin produced from the pulp and paper industry, the BioJoule lignins released are sulphur-free natural lignins that are insoluble in water and suitable for use as raw materials in paint, resin and plastic fi lm manufacture. A subsequent treatment of the chips with high pressure hot water solubilises the xylose. The remaining insoluble solids are mainly cellulose. Cellulose enzyme (initially purchased commercially but later perhaps produced by BioJoule generated yeast strains that secrete celluloses) are added to break the cellulose down to glucose, and then yeast ferments the glucose to ethanol. Biojoule believes it can improve the processing pathway in several ways. Firstly, by using an advanced biological pretreatment step to enhance the release of lignin from cellulose, secondly by streamlining the processing to make more use of local sources of cellulose enzymes to degrade the cellulose into fermentable sugars, and finally, by finding microbes that convert several types of sugars to ethanol more efficiently. In addition, the company would like to modify the whole process to run as a continuous flow system rather than batchwise, which is how other experimental cellulose-to-ethanol plants overseas currently operate. New Zealand was the first country to implement continuous flow beer brewing, and we also have great experience in milk processing and papermaking, both industries with engineering parallels to ethanol production. BioJoule actually aims to develop licensable technologies for efficient bio-refineries. These technologies will encompass know-how and intellectual property spanning the development of biomass, including micropropagation, nursery and plantation development through to engineering issues associated with processing and refining of the biomass to generate products including ethanol, natural lignin and xylose. The company hopes to license the technology overseas and generate revenue internationally—once it has proved the system locally. The Salix cultivars it is testing can be harvested at any time of the year and will grow in any temperate country. No other cellulose-to-ethanol operation is also producing xylose and natural lignin, products for which there are substantial markets and which will also greatly improve the economics of ethanol production. Modelling suggests that a biorefinery should, ideally, be located within a 20 km radius of Salix plantations. In Sweden there are 15,000 ha of Salix plantations. The trees are burned to generate electricity and a similar scheme is being tried in Britain. A plantation of 2600 hectares would provide 100 dry tonnes per day for processing with an output of 30,000 litres of ethanol per day, plus lignin and xylose. A refinery of this size is estimated to cost $50 million. In New Zealand, 42 per cent of energy use is for transport fuels. We import 3,200,000,000 litres of petrol annually. The government has introduced legislation allowing the sale of E10 blends, and E3 blends have also been discussed. It has also committed to zero transport tax on ethanol fuel sales. So far, it has not set a timetable for introducing ethanol blended fuels. Moving to E10 fuel means that we would require 320,000,000 litres of ethanol a year. One $50 million plant could produce about 11,000,000 litres of ethanol annually, so we would need 25 such plants of this size, although larger plants may prove more economic. The willows needed to fuel these plants would cover 76,000 ha. For comparison, forestry covers 1.9 million ha, dairying 2 million ha, sheep and beef 10 million ha, horticulture 110,000 ha. In the Taupo area, 76,000 ha of land is suitable for growing Salix. The small trees would be very densely planted, and mechanically harvested, so slopes up to 15 degrees would be suitable. A number of plastics and similar industries are setting goals of adopting P10 (10 per cent of raw material from renewable sources) to reduce dependence on petrochemicals from fossil sources. Biojoule estimates that farmers could make $300—350 per ha per annum from Salix growing—more than most make from sheep and beef farming at present. The Taupo area offers a couple of advantages to BioJoule. Geothermal steam energy could be available for processing, reducing energy costs. There is much concern about eutrophication of the lake water through agricultural runoff. Converting farmland to trees would reduce this problem substantially. The matter of reducing processing energy is worth a comment. Some people hold that the whole business of converting plant matter to ethanol is a nonsense, because the process consumes more energy than is finally present in the ethanol produced! In contrast to maize where for each Joule of energy used in the process only 1.6 joules of energy are produced, Salix produces an amazing 11 –16 joules. Indeed, the International Energy Agency (www.iea.org) projects that woody crops such as Salix will be major contributors to fuel production from biomass in the future. The world market for ethanol is potentially vast. The gap between the current level of fuel ethanol production and amounts countries around the world aspire to use as a petrol replacement by 2010–2012 exceeds 50 billion litres. Higher targets for 2020 will increase this amount substantially. Globally, energy security is increasingly seen as an intrinsic part of national economic prosperity. Until an alternative new fuel emerges, ethanol will likely contribute to economic growth in virtually every economy. In New Zealand we are witnessing a confluence of the need for energy supply at reasonable cost, the need to remediate waterways and lakes threatened by eutrophication due to fertiliser use and animal effluent, and concern about likely global warming due to the burning of fossil fuels. BioJoule’s proposal offers real progress on all these issues.
Far too many folk know I was once a geologist. For such folly, I am often quizzed about this or that rocky feature. Some striking roadside formations in Rodney County are a recent case in point. A certain editor must have had too much time on his hands some months back. He found himself on Rodney Road, a dead-ender running west towards Mount Tamahunga off the summit of the Leigh–Pakiri road, 100 km north of Auckland. The views from here are fabulous, taking in Whangarei Heads and the Hen and Chicken Islands to the north, Little and Great Barrier Islands and the Coromandel across the water to the east, and the islands and headlands of greater Auckland’s eastern reaches, with the Hunua Ranges beyond, to the south. A picture-postcard spread of Whangateau and Tawharanui Regional Park occupies the southern foreground. The white sands of Pakiri glisten below to the north. Near the end of the road, the editor reported finding, “large rounded rock masses...piled up in the paddocks and along the road side...shaped like squat bananas... formed in light coloured rock”. The largest he claimed to be over 3 m high. They were quite unlike the well-known spherical mega-concretions of Silverdale that resemble giant marbles, he declared. So what were they? My partner and I had planned a weekend away from the computers and the Leigh hinterland offered as good an escape as any. With the weather hot and sunny it was a grand occasion to go forth and examine the nature of the editor’s rocks. However, although 37 years chasing students around lower Northland had left me with a reasonable knowledge of its highways and byways, Rodney Road had passed me by. Confirming we had the right location was not straightforward, given that a crucial signpost had been vandalised in the way of today’s world. It was a typical Kiwi metal road, the sort that used to be described as Grade III in my youth, when I walked such stony trails. Some nice homes occupied the first kilometre or two, and we noted some interesting, partly grassed road cuttings containing large rock masses worthy of later inspection. We were perplexed when it seemed we may have missed our target rocks, but then we swung round a corner, drove up a slight incline and there they were—like mushrooms sprouting after summer rain. Over many years I had learned not to rush to judgement and to refrain from making geological identifications from a car window. We stopped. We got out. We browsed. We mused. We photographed. And then we had lunch. Some of the rocks were oval, others amygdaloidal, one or two crudely cylindrical—the editorial bananas. A few were spherical but most were discoid. Sizes varied. The most curious feature was that all were perched on edge in a most unnatural-looking manner. At the end of the road one shattered example lay inside a gateway. Its interior showed it to consist of very coarse, crudely layered, muddy sandstone containing numerous large pebbles. A second boulder, intact, was perched alongside on its narrow base, surrounded by freshly dug earth. Scars on its surface from steel hawsers and chains were clearly visible. Mystery solved. It had recently been erected. We were looking at standing stones, or menhirs; that is, blocks of stone removed from their natural location and erected on another spot. As we wandered back up the hill we examined others. Clearly, a local landowner, with a lot of time on his or her hands, had been indulging in a little free-stand landscaping. Over a dozen boulders had been heaved upright and each balanced in a relatively small hole, in a manner similar to that in which the European megalith builders of 3000 years ago stood their monuments. On one vacant lot for sale, a foreshortened avenue of stones extended either side of the gate. Finally, on the road out, our eyes now wide open, we noted two recently erected small stones near the front entrance of an up -market property. The source of the stones is the hills themselves. The parent rock of much of the area, including the main ridge and presumably Mt Tamahunga, is 20-million-year-old Waitemata sandstone, laid down in very thick, coarse beds. This rock is relatively impervious to water, but the beds have been broken into large blocky slabs by ancient movements of the earth’s crust. Water percolates down the fractures that separate the blocks and initiates weathering on and along the blocks’ surfaces. Gradually the blocks’ outer surfaces alter. Clay minerals form, their presence causing the outer layers of the blocks alternately to shrink and swell as the supply of ground water decreases and increases with seasonal rainfall. This slight movement is sufficient for the outer altered skin to crack and expose fresh rock beneath, allowing the alteration process to start anew. As the years go by, more and more altered layers develop about each block, like so many onion skins. The process is known as spheroidal weathering. Where erosion of a slope occurs, blocks may become exposed on the surface. The outer layers now slough off under the influence of sun and rain. The relatively unaltered inner rock remains. For obvious reasons these residual masses are known as core stones, and it is just such core stones, in their wide variety of shapes, that have provided an outlet for someone’s creative urges. Those wanting to see the various stages of core-stone production could do worse than visit Buckleton Beach, 20 km south on the northern side of Kawau Bay. At its south-western end, rocks in the intertidal zone and the cliffs consist of fractured, coarse Waitemata sandstone. Wave-cut sections through the blocks show all the stages of spheroidal weathering. Visitors to Rodney Road can inspect large, onion-beskinned blocks of the same coarse sandstone in roadside cuttings, but this isn’t an entirely safe place for recreational viewing. The road is narrow and local vehicles travel fast. Auckland history buffs may recall that in the 1840s and ’50s, buildings throughout the region made use of sandstone won from Mahurangi—the same sandstone of which Rodney’s menhirs consist. The chimney and pump house of the Kawau Island copper mine were constructed from this material, as were the window lintels and sills of St Andrew’s Church in Auckland’s Symonds Street. After a few months’ exposure to the elements, these structures began to degrade. The church’s lintels and sills required patching within a few years, then coating and, in some cases, finally replacing with concrete. A similar degradation awaits Rodney’s standing stones, but for the moment they provide a grand echo of the past—and leave me in profound admiration of those ancestors of mine who built the stone circles of Avebury and Stonehenge. Not only do the sarsen stones of these prehistoric structures consist of extremely hard quartz sandstone that has withstood the elements for millennia, but there was nary a JCB or D8 in sight to assist the ancient master builders transporting and manhandling them. Each stone mass was dragged into place and erected by hand—along with much sweat, blood and tears. The average weight of each Ave-bury sarsen is 40 t. Recently a 100 t monster has been located buried near the main circle. Readers who opt to inspect Rodney’s new menhirs may like to estimate their weight while they picnic and contemplate the magnificent views on offer.
What would have greeted you, stepping out of a waka 800 or so years ago? As familiar as we are with this land under our feet—its outlines and hues, sounds, aromas, the critters that share it with us—our familiarity is with a land that has undergone gross transformation in a relatively short space of time. Step out of a boat today and you will encounter patches of bush, perhaps, or more likely rolling hills of green pasture, salted with sheep and peppered with fences. Roaming these hills a geological blink ago were unique flightless birds, many of them giants of their types, dwelling under a thick canopy of massive trees and prehistoric ferns, forests that were interspersed with extensive wetlands. Present day bush containing stands of native trees are only remnants of the great forests of kauri, kahikatea, totara, beech and rimu that once were. The modern dawn chorus is, likewise, a faded echo of past times, diminished in volume and with some tonal ranges now completely missing. Where, these days, might you find a choir incorporating the boom of moa and kakapo, the ululation of laughing owl, the grating exclamation of adzebill and a panoply of defunct or near defunct songbirds like huia, kokako, saddleback? Te Papa—that’s where! Blood, Earth, Fire is the label of a new, long-term exhibition on Te Papa’s Level 3. It examines the impact of human settlement on the land and the struggle to survive these changes for these hitherto untouched islands’ ark-load of native species. This is an ambitious project given the extent and momentum of change and the time spans involved, but then, Te Papa, with its resources and expertise, is certainly better equipped to tackle such a challenge than most. Beginning with Maori exhibits—intricately carved burial caskets for afterbirths and a selection of worked stones such as pounamu—a thread of settlement-exploitation-miscalculation-mishap moves us quickly to alien introductions. Organisms like kiori and other more recently introduced species of rat, domestic animals, livestock released for decoration or as game, and a long list of pests and biological invaders, are posed provocatively together to hint at the size and spread of this unlikely army. Value judgements are cast aside in labelling family pets, farm and work animals with vermin. All are equal, being equally alien, thus challenging natives for their livelihood. Exotic flora and associated products including fruit and vegetables, many of which are mainstays of our economy, are also packaged with their pestiferous enemies and you can even walk through a quarantined container where fruit fly maggots are writhing among imported foodstuffs, or pause to consider a blender allegedly containing rabbit calicivirus, an introduced disease to control an introduced pest. This, then, is one barrel of the smoking gun. In an adjoining space: the other barrel. The orchestrated process of breaking in the land for human habitation is documented, starting with deforestation and general land clearance which had a duel purpose of sourcing timber for construction while making the land receptive to cultivation and animal husbandry. Farming and rural sector industries are looked at closely. There is even a running collage of 60’s and 70’s TV images: Fred Dagg, Country Calendar, Chesdale Cheese, Scotty and Crumpy, the tailored version of rural life which has been digested and processed into our self-image by an increasingly urban population. A shadowy alcove houses the land that was, replete with life-sized and life-like fauna. Te Papa claims a first—they have deduced through research that the moa (in this showcase, a family of stout-legged moa) was hunched and long, dinosaur-like rather than giraffe-tall in bearing. This doesn’t actually seem like anything more than commonsense. Perhaps their research was based on Issue 12 of NZ Geographic from 1991, which showed and explained why the moa would adopt this pose? But let’s not be picky, these are fine models, hardly discernible from exhibits composed by taxidermy, and they are accompanied by the sounds that these creatures might have produced. The dawn chorus they have recreated is vivid and unique, and the overall effect of this exhibit is rather similar to our Extinction in the Land of Birds poster from issue 44, where an unlikely gathering of different species of birds share a small clearing. In a small theatrette, a looped film called My Place singles out small corners of New Zealand as the (now not so) secret places of artists, adventurers and others who have cultivated a special bond with the land. Particularly notable is the manic passion of a man who throws himself off high ledges in a remote West Coast location to see if his parachute will work. In inimical Te Papa style, the whole exhibition is littered with virtual entertainments, from sawing down your own giant tree to experience the effort required, to prompting a moa to pass faeces with farts and comical expressions and then studying the dung pile for its dietary secrets. This will surely be popular with youngsters. Many of the displays are augmented with excellent maps produced by GeographX, who incidentally provide cartographic services for this magazine. While generally light on accompanying explanatory detail, this is a visually and aurally evocative exhibition, an education and an entertainment, clever in the way it combines so many disparate yet familiar elements into a strong thematic experience. While there is clearly a sense of sadness attached to extinctions and other losses highlighted in this exhibition, there is also an attempt to celebrate conservation efforts and to illuminate as positive developments some of the changes that have been wrought on the landscape. The conjoined Maori perspective lends another resonance to the overall enterprise. As this is the first in a series of long-term exhibitions, you have—presumably—plenty of time to see it. Admission is free.
Kairara: one blink and you will miss it. It’s nothing more than a few farms scattered at the base of Tutamoe Mountain, about 20 km north of Dargaville. Not a tourist in sight on the day I passed through—or on any other day for that matter. Kairara is, for want of a better word, obscure. But behind this out-of-the-way settlement lies a secret from the past—a secret that I had long wanted to discover for myself. However, “wanting” and “doing” can be two entirely different matters, and I pondered this fact as I wound my way through the dusty roads to the base of Tutamoe Mountain in late March. Was my quest inspirational, or just plain foolishness? The closer I got to my destination, the more it seemed like the latter. Not that I hadn’t planned things. Before setting out I had enlisted help, the best help. Renowned conservationist, Stephen King, and local kaumatua, Davis Paniora (Te Roroa), had agreed to be my guides for the day. If anybody could track down the secret of Kairara, surely they could. But did I really know what I was looking for? If the mountain had any answers that day, it wasn’t giving them away. Though bathed in warm sunshine, Tutamoe’s rugged flanks looked dark and forbidding. Only the occasional lone kauri dotted through the paddocks offered any clues of the purpose of our visit. At the bottom of Tutamoe the grasslands were abruptly replaced by forest. Not kauri, however, as you might expect, but pine. Here, as elsewhere in New Zealand, it is a familiar story: native forest logged or burned, and replaced by the “miracle timber tree”, Pinus radiata. We got out of our vehicles and proceeded on foot. I felt oddly cheerful. Beneath the pines the light was soft. Thick layers of pine needles, which had suppressed most of the undergrowth, made for easy walking. We talked as we trekked upwards, ruminating on the past and its legacy: the kauri bonanza of the 19th century, the logging, the gum-collecting and, most shockingly of all, the burnings. In the late 19th century the drive to clear land for new farms reached a crescendo in New Zealand and the match was quicker than the axe. Summer after summer the settlers’ fires raged, and vast stands of kauri (and other valuable timber trees) simply went up in smoke. In a few short decades the kauri forests were decimated. No one knows exactly how much kauri was lost, but the forests that survive today are mere fragments of what existed. Mature, large kauri are especially rare; incredibly, they are to be found over only 1 per cent of their pre-human area. Tutamoe had once been home to large kauri. Even at the end of a dry summer, the slopes were cool and damp. It seemed difficult to believe that indiscriminate fires had raged here, too. Then, just ahead, we saw the proof: blackened stumps. They were kauri, unmistakably. Massive stumps dotted between the pine trees like ancient gravestones. Suddenly, the pines seemed like very poor substitutes. Further on, there was more proof. Rising above us, like apparitions, were the ghostly trunks of large kauri. The charred remnants of the trees rose upwards—six, eight, even ten metres, and then stopped. In the dim half-light of the forests they seemed unreal. Frozen in time, their trunks burnt hollow, unchanged for over 100 years except for the mosses that covered them. Our mood was sombre as we passed by these cremated ruins. I had seen for myself the sad truth: that the slopes of Tutamoe Mountain had once been full of kauri—giant kauri. Yet even as I reflected on their demise, I pondered on their beginnings. I put the question to King: why did kauri grow to such massive proportions on Tutamoe? Was it luck? Was it genetics? Or were there other factors? According to King there are various theories, of which genetics certainly plays a part. But on Tutamoe there were probably two main factors. The first is the soil. Tutamoe is composed primarily of soft sedimentary soils, which enable kauri to establish deep roots and gain good access to summer moisture. Basalt rocks also abound on the slopes of Tutamoe. Originally from the ancient Waipoua volcano, the rocks are rich in minerals which, over the course of time, add fertility to the soil. Almost all the really large kauri today are found on sites with deep, relatively fertile soils. The other important factor relates to the kauri’s longevity. Of all the 15 kauri species found in the Pacific, the New Zealand kauri (Agathis australis) is not only the largest, it is by far the longest living. Extreme longevity, however, poses certain challenges. It means that a tree must be able to survive catastrophic natural disturbances such as floods, fires, landslides and extreme winds. Ecologists now know that natural disturbances have been a major influence in vegetative patterns and processes in New Zealand’s pre-human history. Only kauri that were lucky enough to avoid these natural disasters could reach great size and age. Good luck for a kauri often meant a good location. And Tutamoe Mountain, as it happens, had good soil and good location for long-living kauri. For a start, the bulk of the Tutamoe Range provides good protection to its southern side from cyclonic events that periodically batter the northern North Island. Neither was the mountain at risk from flooding. Even more significantly, Tutamoe’s cool, moist slopes would have offered natural protection from fires and drought, the latter being a primary limiting factor for tree size and longevity. Thus, blessed with a favourable location, some kauri were able to grow undisturbed for thousands of years. Thousands of years? Remarkable, but true. Worldwide there are few trees with lifespan measured in thousands of years, but the kauri is one of them. Only 20 km north of Tutamoe stands Tane Mahuta, the largest living tree in New Zealand. Its age is estimated to be at least 2000 years; nearby, Te Matua Ngahere is thought to be about 3000 years old. And there were others that lived even longer... Proceeding up the south-eastern flanks of Tutamoe Mountain we left the pines and entered regenerating native forest. Here the undergrowth was thick. Suddenly, walking became difficult. The forest seemed to close in around us, and although I was relishing the native bush, I felt my spirits beginning to flag. Perhaps the last part of our journey would be too difficult. There was a clearing ahead of us, a chance to stop and reassess our situation. Maybe cut our losses and head back. I glanced ahead to King. He had stopped on the edge of the clearing and was smiling back at me. I felt momentarily puzzled, but as I drew nearer, King nodded. My pulse quickened. Was this really it? Was this the tree? I looked upwards, upwards...And there, towering above me was...nothing. There was no tree. Only empty sky—and the memory of something that had existed. But I imagined the tree. I imagined it above me, filling the sky. “Kairaru” they called it: the largest kauri ever officially measured in New Zealand. It was big, so big that when Percy Smith first discovered it in the late 19th century, he mistook the trunk for the side of a cliff. Which is not surprising when you consider how big it actually was. In height and girth it was almost half as big again as the legendary Tane Mahuta. Even more incredibly, its timber volume is estimated to have been triple that of our largest living kauri. But not any more, for Kairaru, like so many of our kauri giants, is but a distant memory. For 4000 years or so, it grew safely on the slopes of Tutamoe. It pre-dated the early civilisations—the Persians, the Greeks and the Romans—and outlived them by more than 1000 years. By the time Maori first arrived in Aotearoa, it was a giant. And so it kept growing, slowly, as the centuries rolled by ...until one day, in the smoke-filled summer of 1891, it fell victim to a careless fire. The loss of Kairaru hung heavily over me that day. It seemed as senseless and wanton as the sacking of Persepolis. Yet standing in the place where Kairaru was once rooted gave me strength, too. Like past civilisations, a mighty tree can have a great power, even in memory. That strange power, fuelled by the memory of something both ancient and wondrous, is perhaps the greatest legacy of Kairaru. I had discovered for myself that there is more to a tree than meets the eye. And it was fi tting, I thought, as I paid tribute to our greatest invisible tree, that I should be standing shoulder to shoulder with King and Paniora. They understand the ancient power of the kauri. And their work, for the Waipoua Forest Trust,is all about protecting and restoring the kauri forests for the new millennium. One day, perhaps, there will be a new Kairaru.
While I was chatting recently with Erick Brenstrum from MetService (who writes our weather columns), he told me that the April 2006 temperature for Svalbard Island was 12.4°C above the 1961–1990 average. In fact, every one of the last six months has been significantly warmer than normal. Although the island is at 80°N—well north of Norway—the surrounding sea was ice-free in January. Global warming is predicted to be more rapid and severe in the Northern hemisphere than the Southern because land heats more rapidly than ocean and there is a lot more land in the Northern hemisphere. Nonetheless, researchers are taken aback by the magnitude of apparent warming in the Arctic. The North Pole could be free of ice in summer within 10–20 years! Many scientists and activists are insistently convinced the world needs to take urgent action to avoid uncomfortable warming. The Kyoto Protocols increasingly look too little too late, and New Zealand has so far done little to reduce its production of greenhouse gases. In the GeoNews section of this issue is an account of a detailed proposal by a new NZ company, BioJoule Technologies, to produce fuel ethanol from plantations of special willow cultivars. BioJoule is being set up by Genesis Research and Development of Auckland, established in 1994 as the country’s first biotechnology company. Last year its founder, Jim Watson, was president of the Royal Society of New Zealand, an indication of the esteem in which he is held. The BioJoule proposal deserves to be taken seriously. Ethanol is a proven fuel for vehicles—we even had a few buses running on the related methanol on the streets of Auckland back in the days of the Liquid Fuels Trust Board in the 1980s. Producing ethanol from plant cellulose as BioJoule proposes has only become economically feasible since fuel prices have risen so dramatically. The economics of the project are strengthened because a useful sweetener (xylitol) and natural lignin—a wood-derived replacement feedstock for many chemicals and plastics—would be simultaneously produced from the willows. Since the fuel is being produced from plants, it recycles atmospheric carbon rather than adding more, as happens when fossil fuels are burned. But not only does ethanol have the potential to reduce our greenhouse gas emissions, it would save foreign exchange (remember our current accounts deficit), create local industry, provide a new economically viable agricultural enterprise and by supplanting some animals, help to reduce eutrophication of lakes and waterways. Biojoule estimates that to replace 10 per cent of our petrol with ethanol (320,000,000 litres annually) would require 76,000 ha of energy plantations and about 30 $50 million bio-refineries, although fewer, larger refineries could prove more economic. Vehicles can be modified to run on pure ethanol, however the present proposal is for a 10 per cent ethanol 90 per cent petrol blend initially, but the ratio could be easily increased later. BioJoule has willow trials underway already and now seeks $5 million to construct a pilot plant for making ethanol, xylitol and lignin. I don’t think there are many downsides. Some would lament the loss of land from more traditional agricultural products. There have been suggestions that ozone and some other organic chemical undesirables are produced at higher levels by ethanol-fuelled engines. Social engineers may not like ethanol because it could enable a continuation of our profligate ways with cars. Some would like to see the use of private motor vehicles curtailed, peri-urban sprawl reined in and public transport re-enfranchised. Despite these quibbles, I think that the BioJoule proposal deserves our strong support. Liquid fuels represent only a portion of our energy requirements. Although there are trials in Europe using willows as fuel for power plants, better possibilities may exist. For New Zealand, with a small population and a windy aspect, wind and perhaps tidal power might just suffice. Where populations are dense and wind and water in short supply, other measures will be needed. Solar panels remain expensive, although supposedly always on the cusp of major cost reductions. However, by far the most interesting possibility I have read of in the last six months is a modified form of nuclear generation. Nuclear is, of course, the energy of the universe. It heats the deeper layers of the Earth, fueling volcanism, and powers the Sun and stars. Surely to be pro-solar and anti-nuclear is the ultimate in NIMBYism! Last December’s Scientific American contained an article dealing with advanced liquid-metal cooled reactors (ALMR), in which fast neutrons heat liquid sodium to eventually produce the usual steam. Almost all of the world’s 440 reactors use slow neutrons to heat water, a different process. These reactors offer several significant advantages. Present reactors use only about five per cent of the energy present in their radioactive fuel—the rest ends up as waste. ALMRs use 99 per cent—they burn almost all the fuel. A large power station would produce half a cubic metre of radioactive waste a year and that waste would only need to be stored for 300 years. Furthermore, most existing radioactive waste could be reprocessed into fuel for these plants so no new uranium would need to be mined for hundreds of years. Finally, they can be run so as to produce no plutonium suitable for weapons manufacture. And no greenhouse gases. A tantalizing prospect indeed.
Decades of phosphate mining on Banaba/Ocean Island left it unfit for growing and gathering food, so the islanders who lived there were resettled on Rabi in the Fiji group after WWII. Most remain on Rabi living a subsistence existence but some still dream of far-off Banaba, now part of Kiribati.
Our islands were the finish line for the longest and closest race in human history. A hundred thousand years and more out of Africa, the modern human odyssey of global colonisation ended when the inheritors of two different maritime technologies reached these shores. And the contestants reached the line just 350 years apart, a veritable photo-finish in geological and evolutionary time. The competitors in the human race to Aotearoa/New Zealand started out in opposite directions. It was a handicap race as well, with the longest head start in history. Very early on in the story of modern humans, maybe 100,000 years ago, ancestors of the first group left Suez and walked east, right across Asia. When they were finally confronted by the Pacific, they spread along its shores, heading first, so far as we know, south and east. Their advance did not stop until people were walking on Bondi Beach and watching birds of paradise in New Guinea. Before their odyssey ended, and 50,000 years after their ancestors left Suez, these travellers had made the first truly deep water crossing in history, across the Timor Sea. As people spread across the driest continent, their fi res and appetites changed Australia’s environment, fauna, and flora forever. But the sea barrier of the Tasman was too wide to cross with their technology, so the travels and the changes stopped—for the moment—on its western shores. Nearly 40,000 years after people first camped in Kakadu, and as the most recent Ice Age waned and the great ice sheets of Canada and Scandinavia melted, a final pedestrian human occupation of new territory heralded the end of the American wilderness. Within the geological blink of an eye, people advanced across the dry land of Beringia—now the shallow Bering Sea—passed down the opening corridor between the massive Rockies and Laurentide ice sheets and walked from Alberta to Tierra del Fuego. The mammoths, mastodonts, sabrecats, lions, cheetahs, horses, camels, giant sloths, and other naïve fauna ebbed away. By 10,000 years ago, all were gone, and people were the top predators in a depauperate New World. Europeans have always regarded the cultural, altered landscapes they wrested from the native Americans as a primeval world. In truth, the “American wilderness” that greeted French voyageurs, Hudson Bay Company trappers, and Lewis and Clark was a chimera; the real wilderness was long gone. Wait another 4000 years. The world is warmer and more benign than it has been any time in the previous 100 millennia. A group of fishers at the western limb of the Pacific human arc that spreads from Australia to Patagonia invents the sail, and learns to harvest the wind’s power. With lateen sails on their outrigger and double-hulled vessels they venture offshore. Now, they can travel farther, faster, and safer than almost anyone else, and they become masters of the Pacific’s vastness. These voyagers, the founders of the Austronesian peoples, spread out and down along the already occupied coasts of South East Asia, along New Guinea’s northern coast, meeting and consorting with the descendants of the first migrants, until in the Solomon Islands they were at the end of a springboard to the Pacific. From the Solomons they crossed and recrossed the vast open waters between braids of islands, peopling almost 25 per cent of the globe within just a couple of thousand years. They settled on the scattered shards of land, exploited the virgin resources, changed the landscapes, and made the Pacific their own. By the time William of Normandy was listing his English conquests in the Domesday Book, their travels had taken them from the Straits of Formosa to Easter Island (and probably South America, too), and north to Hawaii and south to the southern Cooks. The other group destined to make our history invented their own sails, probably in or about the Nile valley and eastern Mediterranean, at about the same time as their distant cousins to the east. Gradually, these western sailors ventured along the coasts of the inland sea and then through its narrow western portal, west to the Canary Islands, and north to the Baltic and beyond. Still others went east, down the chute of the Red Sea and out into the Indian Ocean, maybe even all the way around Africa and home again past the Pillars of Hercules. Both these traditions established their own patterns of discovery, occupation, and trade. Arabia, India, and East Africa came into the orbit, and developed their own ways of navigation, based largely on the lateen sail, and linked eventually with square-sailed navigators coming from eastern Asia. Southern offshoots of the lateen-tradition reached the north and west of Australia, and initiated a new era of change, wrought largely by the dingo, but that still did not reach beyond the Tasman’s western shores. Having experimented and explored their abilities, the exponents of eastern and western sailing technologies then shrank the remaining untrodden planetary wildernesses to the South Pacific and remote, inhospitable Antarctica itself. After a brief pause, as if to catch breath before the final effort, people from the Pacific and from Europe set out to conquer the final frontier. And the largest habitable land on that frontier was Aotearoa/New Zealand. The final thrusts of this global pincer movement were made from the north-east and south-west. First, about AD 1290, a bare 50 years before the Black Death brought Europe to its knees, people from the southern Cook Islands established permanent settlements here. That epochal event ended forever the supply of significant, habitable, places on the planet where humans had not diverted life’s evolutionary stream, and nutrient flows to their own ends. It was, literally, the end of the “natural” world. And the Polynesian settlers nearly met their competition head on. Only a hundred years after people began living at Wairau Bar, near Blenheim, an unparalleled, concentrated burst of technological innovation and fervour for exploration and gain began on the other side of the world. Western Europeans spread rapidly and suddenly—within a span of 150 years—west, south, and east. They entered the Pacific through its three easiest doors: Magellan’s Straits, across the swamps and mountains of the Darien at America’s waist, and down the old Austronesian track from Asia. By the early 17th century, the annual bullion runs of the Spanish “Manila” galleons were taking spoils from the American colonies west from Acapulco, Dutch and English ships were coasting western Australia, and Drake was surprising—and upsetting—Spanish shipping off Peru and Panama. Then, just before Christmas 1642, the pincers closed, in a meeting off Golden Bay that was marked by mutual xenophobia and misunderstanding. The near synchronicity of the arrivals is stunning, but much had happened here in the bare 350 years between Polynesian colonisation and European contact. The New Zealand megafauna and much of its most productive vegetation had gone forever. The first colonists had, in that brief period of history, by necessity come to terms with life “the morning after” in the coolest and least productive environment they ever settled. Archaeology is, ultimately, the scientific and sociological plotting of the progress of modern humans from Africa to Aotearoa/New Zealand. The many diversions and delays while technology caught up with ambition and temptation are just embellishments of the record, until history takes up the human tale. The growth of wealth and power in Europe, and of trans-oceanic transport on a comparative shoestring in the Pacific, allowed humans to overcome, eventually, all geographic barriers. The Americas not only acted as entrepôts, they provided the treasure that was both goal and resource for European expansion, and a staple foodstuff for the final Polynesian voyagers. The South American sweet potato was the final horticultural innovation for the eastern migrants. Brought back across the ocean, it then fed New Guinean highlanders as well as Peruvians; a gift from the occupants of the New World to the oldest refugees of the Old. For humans, the 2000 km of ocean around Aotearoa/New Zealand proved to be the most durable geographic barrier of all. It took almost 50,000 years from the first footprints on Bondi until human eyes could gaze out west across the Tasman Sea. The monumental flanking assaults on the final wilderness were over. But once Aotearoa/New Zealand’s isolation had ended, there were no more wildernesses, just different patterns of human involvement with different environments. So, we have the privilege of being closest in time to the final true pioneers, and the final example of an untouched world. We should cherish and honour both heritages, as joint stewards and near-simultaneous discoverers—and exploiters—of the last wilderness. And for the human side, mostly we do. But often more in the breach than the observance. Take, for instance, the oldest substantial dwelling identified so far in the South Island. An East Polynesian-style house stood on the lowest terrace north of the Rakaia River mouth. The land around it is now a 20 ha paddock and camp ground, but when it was occupied the moa ovens on the terrace above were fresh. Its postholes were revealed only when the foundations were being prepared for a new “amenities” building. Construction continued even as the site was excavated. Yes, we actually, knowingly, built a dunny over the remains of our oldest building. You could ask for no more potent symbol for how we, as a country, really feel about our own past in this new land. But, cultural disasters such as this, and the impending loss to “development” of the 700-year-old cultural landscape at Ocean Beach, near Hastings, are nothing to the neglect and mistreatment suffered by the remains of the last world wilderness. Even learned institutions demean it by trivialisation, and we uniformly despise it when it looks like getting in the way of development. The remains of our pre-human past and the sites where they have been preserved enjoy no specific protection in law, and precious little in the public psyche. We have an insatiable appetite for news of new discoveries, but for the moment only, for the post-weather “odd spot” on TV news, and for the exotic. There is little interest in the meaning and significance of the record of our recent past, and little understanding yet of its relevance to the here-and-now, even amongst ecologists. Hence, the record itself is unprotected, except for the scant umbrella for sites provided by some provisions of the Resource Management Act. The only direct legal barrier to overt exploitation has been one provision of the Antiquities Act. And that sometimes fails spectacularly, as a few years ago when a major collection of moa remains was exported without permit and auctioned openly in London, with no repercussions there, or here. The richest recent fossil record in the world—the extraordinarily well-preserved remains of the last wilderness—is therefore in the hands of landowners. Some—the interested few—take great care of the heritage in their hands; most others would if they knew its value; a few actively destroy it to avoid delays in getting returns on investment. While even institutions such as museums and universities emphasise the trivial and sensational and avoid engaging with the values of our older natural heritage, it is unlikely that landowners will get the support they, and the sites they hold in trust, deserve. Even the Department of Conservation, which ministers to the country’s largest estates and the greatest number and variety of sites and resources, still lacks the capacity to understand and conserve the sources of information that should underpin their management and restoration programmes. There is empathy for that record in the conservancies, and some are trying to protect the more important sites. There is little or no support from the centre. It would be much easier to get funds to do even the basics, if the sites contained McCahons. Every art gallery has its catalogue but there is no inventory of Quaternary fossil sites or their values here. We simply do not know what we, and the world, are losing, but judging by the tip of this particular iceberg, it is a lot. Quite simply, these sites and the materials such as bones and other fossils and ancient DNA itself, are our only sources of hard information on what happens when climates change, and New Zealand’s animals and plants and ecosystems have to live in warmer or cooler climates. They are the sources, too, of a rapidly expanding body of information on the way the ecosystems themselves worked, and how they have changed with the arrival of humans on the planet and in Aotearoa/New Zealand itself. Dead bones hold information on environmental temperature, annual and seasonal rainfall, the rate that nutrients such as nitrogen flowed through ecosystems, and the sources of the nutrients themselves. Here are whole encyclopaedias of the past. Pages are being torn from those books daily. Whole volumes are being discarded annually, by well-meaning professionals in other fields, learned institutions, as well as by developers, drainage contractors, and feral goats and possums. If the human inhabitants of Aotearoa/New Zealand, who arrived at its front door almost at the same time, want really to come to terms with their home and to transform the pioneering acquisitiveness of the past (and present) into a mature stewardship of the land, they have to begin by cherishing and understanding the non-human part of the land’s recent past. Regional and national government will have to accept that fossil bones and the swamps and caves they have been archived in are not just curiosities to hoard and to gawk at, but vital links in our chain of being, from the amazing advances of the past, to a fully sustainable future.
Although New Zealand is not a large country, its mountainous terrain usually breaks up the weather so that there are marked contrasts between what happens in the north and south, or between east and west. However, a deep low, such as the one that crossed the country on Sunday and Monday the 11th and 12th of June, can deliver drama to pretty much every nook and cranny of the country, albeit with different flavours in different provinces. As the low approached, warm moist north-westerlies ahead of it produced very heavy rain in the west of the South Island, some of which spilled over the Alps into the headwaters of the hydro-lakes. Colliers Creek in the hills behind Hokitika received more than 350 mm of rain over the two days while Franz Josef had over 400 mm. East of the main divide, some 200 mm fell at several sites in the headwaters of Canterbury’s Waimakariri River, over 100 mm descended on Mt Cook Village above Lake Pukaki, and around 90 mm fell at Makarora at the head of Lake Wanaka. Heavy rain also fell over the ranges in Kahurangi National Park, in north-west Nelson, and across the high country of the North Island from Mt Taranaki to East Cape as well as in the Tararua Range. Damaging winds ahead of the low affected much of the North Island, knocking over trees in many districts and blowing the roof off a house near Wellington. In Greymouth, a small tornado ripped off the porch and front wall of a house and snapped a number of trees off at their roots. But the wind’s greatest trophy was the Auckland power supply. After blowing a few Auckland windows in and dropping some trees over roads and power lines, the wind snapped off a small earth wire which fell over high voltage lines cutting power to over 700,000 people. Trains were stopped and buildings plunged into darkness. People were trapped in lifts until the Fire Service could rescue them. Around 300 sets of traffic lights failed causing major traffic jams. Some drivers left their cars and stood in the rain to direct the traffic, while others improvised their own solutions by driving down the wrong side of the road. Petrol stations were unable to pump fuel and many schools and businesses closed, at an estimated coast of over $50 million dollars in missed trade. And then the snow started. Warm moist air wrapping around the low climbed over cold southerly air sliding up the South Island east coast resulting in the heaviest snow in Canterbury since 1992. Roads and airports were closed and many power lines brought down by falling branches or the weight of the snow on the lines. Fortunately for farmers, it was early in the winter and lambing was still many weeks away. Consequently stock losses were small, although fields are expected to cut up and become muddy once the thaw comes. The melt-water, however, is expected to have a significant impact on depleted groundwater that has been at the lowest levels since records began in 1970. After the 1992 snowfall, some deep wells rose by as much as 5 metres, although it may take three to six months for the water to percolate down. Melting snow will also help lift levels in the hydro lakes that were already boosted by the northwest rain. In Timaru, where the snow was the heaviest to fall in 60 years, the weight of snow collapsed the showroom roof of Hervey Motors and part of Fonterra’s drystore. Hundreds of house verandas and guttering systems were also wrecked. Of course, skifield operators were delighted with the snow. Over half a metre fell on most of the Canterbury skifields and 30 to 40 cm on the Otago skifields, most of which are getting ready to open. Some keen snowboarders even got in practice while being towed behind cars through the streets of Timaru. As well as knocking out power supplies, the snow also toppled some cell phone towers cutting communications in many rural areas. Not all of these services had been restored by the time another, smaller, snowfall occurred just over a week later. The low that brought all this excitement deepened so fast as it moved southeast across the Tasman Sea and New Zealand that it qualified as an example of “explosive cyclogenesis” otherwise known as “a bomb.” This term was coined it the 1970s by meteorologists in the USA studying the development of depressions off their east coast, some of which deepen by 60 hPa in 24 hours—thanks in part to heat from the Gulf Stream. A study of rapidly deepening depressions in the Southern hemisphere found that one of the main source regions for them is over the ocean just east of Australia. Here there is a warm ocean current to help inject heat and moisture into the air, both of which are key ingredients for deepening lows. Also, there is a mountain chain just to the west that helps impart vorticity to airstreams as they rise over them. Another factor is the strength of the upper wind system known as the sub-tropical jetstream. So much air rises over Asia during the monsoon that some of it spills across the equator at high levels into the Southern hemisphere. As it moves towards mid-latitudes the air accelerates into the sub-polar jetstream. This year, as it happens, the Asian monsoon has been particularly active, starting early and causing widespread heavy flooding in many countries. Consequently, the subtropical jetstream in our region has been very strong, reaching speeds of over 300 km/h. A strong jetstream helps deepen lows by more rapidly transporting high-level vorticity downstream from the troughs that move through the mid-latitude westerlies from time to time. All of this geography coming together makes the Tasman Sea a hotbed of weather action. And what an intriguing example of the interconnected nature of the world’s weather—that the heat of the Asian monsoon can contribute to creating the cold of a New Zealand winter.
While all of Westland tends to be damp, southern Westland is moister than elsewhere. Haast receives a healthy 3500 mm of rain a year, but it is more than local precipitation that makes this area wet. A series of major rivers, their headwaters draining the Main Divide from Mt Cook down to west of Mt Aspiring, converge here to empty into the Pacific along only 50 km of coast. Over the last 6000 years, the debris they have carried has built the country's largest wetland plain. Lake Moeraki provides a foretaste of the area to those arriving from the north.
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