The scattering of holdings in the Marlborough Sounds support a community connected and defined by the sea. Matt Philp follows the salt water roads.
Christchurch was built on the pastoral wealth of the Canterbury Plains—a broad, verdant plateau of alluvial outflow from the Southern Alps. It was flat, it was productive, and it became a focal point of intensive pastoralism. Wealth from these holdings flowed through the city, the oldest in the country. With Cathedral Square at its centre, Christchurch was carefully planned, with four concentric city squares and areas of parkland that ring the inner city. Beyond that, the city grew outwards across the plains, and to the east, building over the marshland of the Heathcote-Avon Estuary. While geologists knew that the Canterbury region had suffered earthquakes before, no one could have predicted the Darfield or Christchurch earthquakes, nor indicated the potential severity and long run of aftershocks. “Christchurch is about as far from the plate boundary as anywhere in the South Island,” said GNS Science geologist Hamish Campbell when I called him to get his read on the big picture. “Though not entirely unexpected, no one anticipated that a fault zone would run directly under the city itself, and there is no geological evidence that anything like this has occurred in the last 10–20,000 years.” The past ten months have been a landscape-bending, heart-rending trial for residents—there have been 28 earthquakes greater than magnitude five since September 4 last year. “The pattern of aftershocks could be considered normal,” said Campbell, “but the number of large aftershocks is more than anyone in the scientific community would have expected.” In the weeks following the February 22 quake, it is estimated that 70,000 people left the city, and emigration to Australia is at a 32-year high. Now, as the besieged city is rocked by more violent aftershocks, planners, policymakers and geologists are re-evaluating the location of the city itself. Built on thin alluvial soils, on peat, even on remnant sand dunes, many of the city suburbs—particularly those in the east—have been inundated with liquefacted material erupting through fissures in the ground. Some suburbs have literally sunk into the marsh on which they were built, which officials now contend is no place to live at all. The maximum subsidence due to faulting is 15 cm. It’s not much, but then the suburb of Bexley was only ever half a metre above sea level. Even Cathedral Square has subsided. What’s more, there has been significant uplift at the mouth of the Heathcote-Avon Estuary, creating, in effect, a swamp of the eastern suburbs, if not the city itself. The government has announced that 5100 homes will be demolished in the worst-hit suburbs of Bexley, Avondale, Horseshoe Lake, Burwood, Dallington and Avonside. A further 9000 await more geotechnical analysis. I have heard complaints on talk-back radio that the rebuilding of Christchurch will put an unfair burden on taxpayers outside that city. This is an attitude which—as well as being utterly repugnant—is radically misinformed. A natural disaster like that which struck Christchurch, and continues to batter it, could have happened to nearly any city in the country. Invercargill, Blenheim, the Hutt Valley, the towns of the Wairarapa from Featherston to Masterton, Napier—all are sited on alluvial soils just like Christchurch, and all are prone to seismic activity. And while Auckland is likely the safest city in the country from a seismic point of view, there are 50 very conspicuous volcanic cones to remind residents that New Zealand is a highly geologically active archipelago perched on the Pacific Ring of Fire. The Canterbury quakes are both a catastrophic social tragedy and an object lesson for other cities in the country. This is a national problem which requires a nationwide response. We are, geologically speaking, all in the same boat.
New Zealand’s biodiversity is now even higher. Twelve species of fish new to New Zealand, five new to the Kermadecs Islands and two new to science were discovered in last month’s 21-day Auckland Museum scientific expedition to the Kermadecs, New Zealand’s largest and most isolated marine reserve. Te Papa scientist Carl Struthers described a brand-new species of Lotella cod as a radiant “sunset orange” compared with examples of the genus common in New Zealand, which are a muted reddish-brown. In the coming months, x-ray analysis of the rows of lateral scales and tissues will dispel the possibility it may be just a colour morph. A zebra lionfish—the fourth type of lionfish recorded in the region—was also hauled aboard. Zebra Lionfish are found widely throughout the Indian and Western Pacific oceans, but it is not known whether they breed in the Kermadecs or drift as larvae from the Great Barrier Reef. These solitary fish are armed with venomous dorsal spines—one prick can cause excruciating pain, with the best cure being to hold the hand in extremely hot water for hours to break down the venom protein. Look out for a major feature on the Kermadec Islands in the next issue of New Zealand Geographic.
Huhu grubs may hold the secret to economic biofuel production. Or rather, their guts may. Last year’s global tally of carbon emissions was the highest on record (30.6 gigatonnes), and with fossil fuel supply dwindling while prices continue to climb, the drive to find cleaner and cheaper fuel sources is ever more urgent. Wood waste from New Zealand’s timber industry is plentiful and energy-rich, but there’s a hurdle to harnessing that energy that is both difficult and expensive to surmount: separating the cellulose, which is useful, from lignin, which is not. Lignin is the substance that makes plants woody, but it also blocks our access to the energy-rich cellulose and hemicellulose within. Nature has a few ways to break this lignin barrier. White rot breaks it down with enzymes, as does the New Zealand huhu grub Prionoplus reticularis, but in a fraction of the time. Hugh Morgan from the University of Waikato and his team have analysed the guts of these grubs to discover what makes them so efficient at munching through fallen forests. Using enzymes called laccases, huhu can oxidise in mere hours the quantity of lignin that white rot would take weeks to break down. Huhu can devour the wood at such a fierce rate because they first chew it into small pieces, creating a greater surface area, and the remainder of the digestion is done by laccases in an intestine providing an alkaline and oxygen-rich environment. Scientists are now trying to isolate the hardest-working of these laccases—enzymes which, ideally, will also be fast-acting and cheap to produce, and could be grown in mass without their huhu host. Perhaps someday, a solution to the problems of the modern world will be found in the gut of an ancient New Zealand grub.
Weeds from abroad can be controlled using pests from abroad. The noxious, vine-smothering banana passionfruit vine, Passiflora spp, meets its match when pitted against the moth Pyrausta perelegans, a fellow Colombian which eats the flowers and so prevents the plant from setting seed. However, in a country still ravaged by introductions, caution prevails. Landcare Research imported the Pyrausta moth in June 2010, after years of seeking permission from ERMA, MAF and South American authorities. A storm hit Christchurch the night after the September 2010 quake, and the two events combined disabled Landcare Research’s cooler but left the heater intact, destroying the whole tank of insects. This was just one setback among many. As the banana passionfruit marches forth—individual plants can climb more than 10 m and spread 100 sqm—the time taken to ascertain the safety of an imported specimen can seem painfully long. One important consideration is target specificity. In the case of Pyrausta perelegans, it was found that they attacked New Zealand’s native banana passionfruit (kohia) when planted out in the same cages. However, insects will commonly go for uncharacteristic food choices when supplied with a limited selection in confinement. Scientists shipped the kohia to southern Colombia and planted them on rocky slopes where the moth exists. It took years to obtain the permit, only for the plants to die in unseasonably bad weather six months after being planted out. The lucrative trade of bioprospecting is now considered biopiracy—the commercial use of genetic material in pharmaceuticals and other products without benefit to the country of origin. Half of Chile’s native plants are endemic, and Colombia and Brazil have the highest biodiversity in the world. However, the same legislation that protects material being distributed for commercial purposes also puts limits on biocontrol opportunities, with no distinction between economic benefit to private organisations and the public good. For now, even as scientists and bureaucrats battle it out across borders, the weeds will keep creeping.
The world’s smallest, rarest dolphin lives in New Zealand. After the expansion of gill-netting in 1970, the population and range of Hector’s dolphin diminished rapidly. One extremely isolated subspecies, Māui dolphin, now numbers barely 100 individuals. Yet science has revealed that the species may yet recover, even from the brink of oblivion.
Steve Sawyer winds back Nature’s clock
Modern dive suits are lighter, offer more freedom of movement, and you don’t end up pulverised in your helmet.
Northland seems to have a baffling surplus of coastal scenery, and each twist and turn of the road to Tawharanui reveals another magical indentation. Matronly peninsulas shepherd close-knit groups of islands, and each bay is a slice of summer all year round. Anchor Bay is an open, sandy beach broken with tidal platforms, offshore reefs and headlands with sea caves. Large pohutukawa trees perch on the beach edge. It is hard to walk away from all this, but if you choose to do so, there is a fine walking circuit around the peninsula. From Anchor Bay follow the farm road up onto the broad tops of the peninsula, crossing an ecology trail. There are good views along the farmland past grazing Hereford cattle and Romney sheep. After about two kilometres you reach a track junction that is about 90 m above sea level, where you have the option of following the peninsula out to Takatu Point. You can see cloud-capped Little Barrier Island in the distance, and Kawau Island nearby to the south. Follow the track along the south coast and turn onto the side-track that drops through a shady stream with stands of manuka and puriri, then follows alongside a dam, meeting the ecology trail again on the way. Shortly you exit out to Anchor Bay again and that immaculate stretch of sand.
Though we’ve changed the climate, we're still obsessed with altering the weather.
Derek Grzelewski is one of New Zealand Geographic’s most prolific writers. With stories on trout and salmon in his back catalogue, and living as he does on the banks of the mighty Clutha River in Albert Town, it’s no surprise that he has written a book about the piscatorial life. Trout Diaries draws on Grzelewski’s experiences (usually with dog in tow) over one calendar year starting in October, the first month of the fishing season in most places. Grzelewski’s book is no how-to or where-to guide in fact, he keeps the location of one River X secret but rather chronicles his evolution as a fly fisher. The writing is incisive and full of anecdotes, like riding shotgun with him as he scours the land for new waters and experiences. It is set largely in the South Island (with a couple of forays to the North Island thrown in), a backdrop that many consider to be an angler’s nirvana. Trying to make a living from something you love sounds ideal, yet many anglers-turnedtrout guides have killed their passion by making that very choice. Grzelewski tried it himself for a few seasons, before realising that his clients fished for different reasons. “They seemed to have lost their footing on Earth and gone adrift in a dreamland of sound bites, digitised reality and instant gratification,” he writes. Quite different, then, from Grzelewski who, when camped near Lake Moeraki with his dog, read Nature as Teacher by Viktor Schauberger, the Austrian master forester who could stare at flowing water for hours without becoming bored. Schauberger was a pioneer of vortex mechanics but also something of an iconoclast who believed that water was “a living thing, the blood of the Earth”. He designed successful log flumes in the 1920s but swung from derision.
One hundred years ago, as Robert Falcon Scott and his team fatefully hauled their sledges towards the South Pole, an Australian and New Zealand expedition under the leadership of Douglas Mawson set sail for Antarctica to commence the most ambitious exploration of the icy continent yet undertaken. It was a journey from which two men would not return, and from which Mawson himself would barely escape with his life.
Far from the steely glare of stadium lights our national game takes place in snow and mud in the south, on sun-parched plains in the north, on provincial fields, in back paddocks, back lawns and on beaches. Taking in these themes, a new New Zealand Geographic book captures rugby, the heart and soul of New Zealand, and the landscape in which it is played.
When I call Neil Fitzgerald, he’s seconded deep in the podocarp forests of the Blue Duck Creek Scientific Reserve near Kaikoura. He’s spent much of the day fixing seed traps to totara, rimu, matai, beech and tawa trees devices used to gauge seed production and the response of these forests to changes in climate. Fitzgerald started up this track many years ago. Growing up in Waitomo, he kept pheasants and New Zealand’s native red-crowned kakariki at home, and worked at the Otorohanga Kiwi House in his spare time. His grandfather, who was one of the founders of the New Zealand Photographic Society, gave him a camera at this time, and his abiding interest in ecology became connected with photography. Now working for Landcare Research, Fitzgerald’s work takes him to some hard-to-reach places, including offshore islands accessible only with a scientific permit. In each case, he carts his camera gear along as well, and in downtime or at night-time goes exploring in the nether-regions of New Zealand. “It’s opened my eyes to the complexity and diversity of the New Zealand environment,' he says. “There’s always something to find, even in the most unappealing places, like gumlands.' For his feature in this issue, Fitzgerald spent a total of three weeks over numerous visits capturing the beauty and complexity hidden beneath the scrub of Northland. In places it was dense and hard-going, in others it was soft sand or boggy marshland that slowed his progress. “You can find interesting little critters quite quickly, but finding good examples in nice light can take a long time,' he says. “However, I’ve always found a certain satisfaction in looking for things that aren’t immediately obvious.
Pathogens often leap from animal hosts to humans. Sometimes, virulent strains are also transmissible between people—then you have the makings of a global pandemic..
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