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Exterminators to the world
As we all know, New Zealand's birdlife is under threat from stoats, possums, feral cats, rats and the rest. These pests compete for food with birds, but also devour their eggs and chicks and sometimes the adults themselves. However, since the 1980s, farmers, land managers and scientists have been fighting back and even the sceptics are astonished at the results. Rodents on over 100 islands around New Zealand have been eradicated and on the mainland, pests are being controlled at many sites. During 2006 alone, there were a number of successes. In June 2006, conservationists on the Chathams announced that record numbers of chicks of two critically endangered petrel species (Chatham petrel and Chatham Island taiko) had survived to fledging, due in part to the control of rat numbers during the chick-rearing period. It was also a good year for Little Barrier Island/ Hauturu near Auckland. Cleared of rats in 2004, the island's Cook's petrel population responded two years later with a bumper crop of chicks, judging by the large numbers of recently fledged birds that turned up in the city's gardens in April. Ulva Island in Paterson Inlet was declared rat-free in 1997, and is now a safe haven for saddlebacks/tieke and Stewart Island robins which were reintroduced, followed by common skinks in 2005. Similar celebratory news came in January 2006 from remote Campbell Island with sightings of the first Campbell Island teal ducklings in 100 years. Cleared of rats in 2001 by a mammoth helicopter-led operation, this island at 11,300 ha is the largest rat-eradicated island in the world. The ducklings were the product of a release of 105 teal in 2004 and 2005, and they appeared shortly after the return of another endemic species, the Campbell Island snipe (see NZ Geographic issue 80) There is no doubt that New Zealand is the world authority on eradicating rats and other unwelcome pests. Poisoning every last rat on an island involves a multidisciplinary team, including expert planners, skilled pilots and meticulous field workers. But one aspect is key: it's the conservation managers who lead the way, supported by scientists. Over the past 20 years, skilled rat killers, like DOC personnel Ian McFadden, Andy Cox and Lindsay Chadderton, and freelance practitioners Derek Brown and Kerry Brown, have built up a network of skills and experience, sharing the challenges and victories of island restoration with increasing numbers of island managers world-wide. New Zealand isn't the only country with introduced pest problems. The International Union for the Conservation of Nature lists invasive species as the key threat to island ecosystems. But fortunately for island managers across the world, the New Zealand Government has made its rat eradication methods and specialists available to everyone through the Island Eradication Advisory Group (IEAG). The list of islands where the New Zealand method of rat eradication has been successfully transplanted includes both equatorial islands such as Pitcairn, Fiji, Western Samoa, Seychelles, Mauritius and Hawaii, and higher latitude islands like the Aleutians in the Northern hemisphere and St Paul, Kerguelen, the Falklands and South Georgia in the Southern hemisphere. The successful transplantation is no better demonstrated than in the Falkland Islands and South Georgia in the South Atlantic Ocean. Like many of New Zealand's islands, the British Overseas Territories of the Falkland Islands and South Georgia have endemic species and races of land birds and an abundance of seabirds, including key populations of many of the world's threatened albatrosses and petrels. Forward thinking wildlife conservationists working on both islands initiated rat eradication programmes in the late 1990s by bringing in New Zealand experts. From countless emails and just a few short visits, five Kiwis set up a legacy that provides an enduring framework of habitat restoration. "Successfully transplanting our methods to other island communities relies on three factors," explains Derek Brown. "A meticulous and detailed plan of eradication and bio-security, the development of local expertise and the successful rat eradication of the first few islands." The Kiwi approach has brought resounding success to the Falkland Islands and South Georgia in the last seven years. South Georgia (375,000 ha) is thought to hold up to 35 million pairs of 31 different breeding birds, from the wandering albatross that makes circumpolar migrations to the tiny South Georgia pipit that probably has to be careful not to be blown out to sea. Pipits and burrowing petrels in particular are only found on a handful of rat-free offshore islands or squeezed into the few remaining rodent-free pockets on the mainland, which amount to about 35 per cent of the island's total 1100 km of coastline. The charge against rats was led by Sally Poncet, who has surveyed just about every inch of coastline at South Georgia. "Even on my first visit in 1977, I was struck by the total absence of South Georgia pipits and the smaller burrowing petrels in those areas with rats and the impact that had on the vegetation," Sally explained. "The risk of rats invading more islands and coastline was always there, but it wasn't until 1999 that we were able to start doing something about it: we got government support for a rat eradication feasibility trial which included looking at quarantine issues for the first time." South Georgia is not an easy place to work. It's remote, separated by 800 nautical miles of often stormy seas from the Falkland Islands. Over half of the island is covered in permanent ice, and snow lies down to sea level for much of the winter. Eradication would have to be done during the summer, which means laying bait among all the breeding birds. "Conditions at South Georgia are unique, and I knew we had to get the best advice there was. That's where Andy Cox came in," said Sally. Andy, a member of IEAG and already busy working on the ambitious eradication plan for Campbell Island, was positive that the New Zealand methodology could also work in South Georgia. During 1999 and 2000, Sally combined her local knowledge with Andy's expertise and experience and that of his colleague Ian McFadden. Funding was obtained from the South Georgia Government, and work began on the first stage of investigations, which included testing the suitability of New Zealand bait and methodology, and assessing the feasibility of eradicating rats from discrete areas isolated by glaciers. "Once we had an eradication plan for a trial island, we needed to test it," says Andy, and he and Ian joined Sally and several willing assistants on her family's yacht for two months of field work at South Georgia in November 2000. After examining a range of potential eradication sites up and down the coast, the team opted for Grass Island (30 ha) near the abandoned whaling stations of Stromness and Leith Harbour. Little did the three Kiwi sea kayakers who passed Stromness Bay on their successful circumnavigation of South Georgia in October 2005 (see NZ Geographic issue 79) know that the efforts of their countrymen would also come to fruition that spring. Grass Island was declared rat-free in 2002 but it wasn't until December 2005 when the real success was witnessed. "We saw a South Georgia pipit in display flight during a brief visit in early December," said Sally. "Of course we went back for a second look some days later and were rewarded with the sight of a pipit carrying food in its bill." South Georgia pipits bring food to their incubating mate and then later to the chicks—either way, Sally had a new breeding site for South Georgia pipits. More importantly, it proved how future eradications could work at South Georgia. The Government of South Georgia and South Sandwiches now employs its own island restoration scientist, Darren Christie, who learned his trade with Derek Brown in the Falkland Islands while working as a volunteer for a local non-governmental organisation,Falklands Conservation. The 750 islands that comprise the Falkland Islands are home to 70 species of breeding birds. Of these, small ground-nesting land birds like the endemic Cobb's wren and small burrowing petrels are found only on rat-free islands. On the advice of Sally Poncet, Falklands Conservation turned to New Zealand for help and Derek Brown responded wholeheartedly. For Derek, there was little to go on in the Falkland Islands. "There was a lack of detailed knowledge on the vast majority of islands in the Falklands and where rats were and what effects they had," Derek explained. Derek and his colleague Lindsay Chadderton set about creating an island database using local knowledge and field surveys, and establishing a priority list of islands to be cleared. Without helicopter pilots in the Falklands experienced in aerial application of rat poison, Derek, Lindsay and colleague Kerry Brown resorted to ground-based techniques—either hand-laying of poison in bait stations or hand-broadcasting bait to simulate an aerial bait drop. They started in September 2001 with two islands just outside Stanley Harbour, the home of most residents of the Falkland Islands. "Over two months and a series of small and relatively simple islands, we developed the skills of the Falklands Conservation scientists, including Darren Christie," said Derek. The following year, Falklands Conservation was confident enough to attempt eradicating rats from a further two islands and in 2003, Derek was back once again to assist with a larger scale eradication operation. At 305 ha, North East Island became the largest island in the world where the rat poison was broadcast by hand. Judging by the number of Cobb's wrens and tussacbirds that greeted the zodiac carrying Falklands Conservation personnel on a recent post-eradication visit, the baiting was a success. A visit to the two islands where rat eradication efforts first began also showed a victory—breeding Cobb's wrens. Darren Christie, currently working on rat eradication at South Georgia, recently returned to his Falkland Islands base after a study trip in New Zealand to observe Derek Brown and Andy Cox in action on their own turf. "What I like about the field of rat eradication is that all the practitioners like to work together, to listen and learn from one another's mistakes and successes," said Darren. Andy Cox believes that by "working with other countries, we lift New Zealand capacity as well". New Zealand leads the way in eradication because of this co-operative approach and a curiously complementary mix of meticulous attention to detail and a 'give-it-a-go' attitude. Ironically, the transfer of skills from New Zealand to places like South Georgia and the Falkland Islands might come full circle. Derek Brown predicts that "the Falkland Islands could become a world leader in rodent eradication research, with all its small islands to test new strategies, baits and reduce overall per hectare costs."
New wardrobe
This katydid, Caedicia simplex, occurs in both Australia and New Zealand. It inhabits gardens, parks and similar areas and feeds on foliage of both native and introduced plants. Eggs are laid in late summer or autumn and in spring hatch into a nymph that resembles a miniature adult. As the nymph feeds, it grows and goes through five or six instars, each separated by a moult. Wing buds enlarge with each instar. The insect illustrated is undergoing moulting or ecdysis from a penultimate nymph to the adult form. It is at this stage that the wings fully mature. During the moulting process, the insect hangs down from the old skin until it finally extricates itself. Fluid is pumped into the wing veins, the wings expand and are then folded in the normal resting position along the abdomen to harden with the rest of the new exoskeleton. This specimen is a female. The red colour on the limbs becomes less obvious in adult females as the exoskeleton hardens and darkens to a leaf green. Males retain more of the red colour. This species makes a distinctive soft call, especially in the early evening and at night, the males being more vocal than the females. Adults probably live for two or three months.
Solar Skeleton
As the world ponders global warming and the end of oil, a small subculture of futurists with a view beyond the petrol pump are planning a coming-of-age party in Darwin for October next year. They'll be toasting twenty years of successful solar car racing. In 1983, inspired by the excursions of Paul MacCready in to solar-powered flight, Danish-born Australian adventurer Hans Tholstrup and racing driver Larry Perkins slowly coaxed a "photovoltai-covered bathtub on wheels" the 4000 kilometres from Perth to Sydney. Four years later this spawned the World Solar Challenge (WSC), the epic trans-continental sunlight-powered 3000-kilometre race from Darwin to Adelaide. While Tholstrup's pioneering "bathtub" tortoised along at about 30 km/h, modern solar racers can now sustain over 100 km/h and sprint up to 170. Some even carry a passenger. Numerous events, large and small, now appear on the international solar car calendar, but the WSC, now owned by the South Australian government, is still the flagship event for the maturing brainsport. Second-hand solar cars are occasionally even offered for public sale: there was one on TradeMe recently. In a cramped concrete garage, some clever Christchurch chaps have toiled through the long winter nights to produce the skeleton of a curious vehicle. In the Canterbury University wind tunnel, the car's carapace has also been undergoing aerodynamic refinement. Electrical engineer Rob Glassey and his multi-talented Team SolarFern are planning to fly a lonely NZ flag competing in next year's World Solar Challenge and the chassis has now been completed. They still have to complete the wheels, motor, body, solar panels and electrical work. Al so in Darwin for the WSC anniversary will be a group from Hamilton's Waikato University who are building an electric car for the Greenfleet demonstration section of the event, which provides an opportunity to showcase practical and ecologically sound transport solutions. In spite of the WSC event being "just across the ditch," New Zealand representation has been rather sparse over the years. Stewart Lister's Solar Kiwi cars performed well in both 1990 and 1993 but, so far, have been the only two NZ vehicles to cross the Adelaide finish line. Despite this success, Lister failed to attract funding for the more ambitious two-seater he had hoped to build for 1996. Neville Baxter from Wellington entered the (pedal assisted) solar cycle class in 1996 and despite getting to Darwin, couldn't finish his vehicle in time for the race. A rather novel solar vehicle design attempted by Long Bay College, an Auckland high school, failed in 1993 through lack of money, and another school team, from Hutt Valley High in Wellington, managed to actually start the race from Darwin in 2001 but had to withdraw early beca use of equipment failure. In Christchurch, Team SolarFern leader Rob Glassey is optimistic. He attended the last WSC as an official observer, has done his homework Stewart Lister's Solar Kiwi cars performed well in both 1990 and 1993 but, so far, have been the only two NZ vehicles to cross the Adelaide finish line. Despite this success, Lister failed to attract funding for the more ambitious two-seater he had hoped to build for 1996. Neville Baxter from Wellington entered the (pedal assisted) solar cycle class in 1996 and despite getting to Darwin, couldn't finish his vehicle in time for the race. A rather novel solar vehicle design and has a realistic idea of what lies ahead. The recent official launch of the SolarFern project went smoothly enough in spite of an exuberant Canterbury wind trying to dismantle the display tent. The prototype SolarFern vehicle, still in its skeletal state, took bumps and turns in its stride as it was tested on the tarmac. The finish line in Adelaide is still a long way off, but Team SolarFern successfully cleared the first hurdle at the A&P showgrounds and is up, running and looking good.
El Nino returns
El Nino has crept up on us. Sea temperatures have warmed over the eastern tropical Pacific, both at the surface and at depth. The easterly trade winds that blow across the tropics have weakened and the atmospheric pressure has decreased in the eastern Pacific around Tahiti, while at the same time it has increased in the west, over the area around Darwin. Weather around the Pacific and beyond is already showing the influence of El Nino. Hurricanes and tropical storms have also been partially suppressed over the Atlantic. An active season had been expected, with the number of storms forecast to be well above average including those making landfall on the coast of the United States. As we head towards the end of the season, the number of storms is close to average and only a few, mostly weak storms, have struck the United States. Instead, the hurricanes have tended to stay out to sea, curving away towards Europe, where their remains have brought welcome rain to drought stricken areas such as Spain and Portugal. El Nino has this effect because the warmer waters near Ecuador and Colombia cause increased upward motion in the atmosphere there. As the air rises, it spreads outwards, thereby increasing the westerly winds at mid-levels of the atmosphere over the Caribbean. The stronger winds shear off the top halves of developing tropical storms near the Americas before they can fully develop. Those hurricanes that develop further to the east tend to be steered away from the United States by the stronger westerlies. Over the western Pacific, El Nino has contributed to the serious drought that has affected parts of southeast Australia, where many farmers have had to sell off their stock at low prices, and bush fires have been much worse than normal this early in spring. Lack of rain over Indonesia has contributed to the worst fires there since the El Nino of 1998. Smoke produced by the fires in Sumatra and Kalimantan has drifted over neighbouring countries such as Malaysia and Singapore. Visibility has been reduced to 50 metres at times, disrupting aviation and shipping and causing road accidents. Drinking water has been contaminated in places and the air has been dangerous to breathe, causing schools to close. The fires are started deliberately to clear land for agriculture, not only for small farmers but also for new plantations of palm oil trees. Lighting the fires is illegal but the law is poorly enforced. Some of the fires get deep into peat soils and can burn for years. Worldwide, it has been a bad year for fires. The USA has had its most destructive and costliest fire season in 50 years. Around 9 million acres have been destroyed at a government-estimated cost of 1.5 billion dollars. Poland, Greece, Portugal and Spain were badly affected during the summer's droughts and record heatwaves. In Spain, where the cost of the fires was estimated at 100 million euros, dozens of people have been arrested for arson. Motives range from personal vendettas against neighbours to forest clearance for grazing and employment opportunities for casual fire fighters who are only paid when fires are burning. The strength of this El Nino, as measured by the departure from average of the sea-surface temperatures, is weak going on moderate. Although it seems to be strengthening, it is not expected to become strong, as was the El Nino of 199798. This is partly based on computer projections of ocean temperatures and partly on decadal cycles in El Ninos performance. Long-term fluctuations in the behaviour of El Nino have been identified using palaeoclimate indicators, such as tree rings, which can extend records of weather patterns back hundreds of years. In the years from about 1977 to 1999, El Ninos were much more frequent and stronger than La Ninas. Based on past patterns of behaviour, it seems likely that we are now entering several decades where the El Ninos will be a lot less frequent than they were and not as strong. So what can New Zealand expect over the coming months? El Ninos correlate with more frequent south-west airstreams over New Zealand, which bring more rain than average to southern Westland, Fiordland, Southland and south Otago, while conditions are drier than normal over the top of the North Island and east of the main ranges from Gisborne to north Otago. On the whole, the country tends to be cooler than average but eastern areas can be warmer because of more frequent fohn winds blowing down from the mountains. These winds bear very little moisture and further dry out vegetation already suffering from lack of rain, thereby adding to the fire risk. New Zealand has already had an early start to its fire season. Severe gale north-west winds in eastern areas of the South Island have caused a number of fires to burn out of control. In Dunedin, a fire in pine forest threatened the suburb of Ravensbourne. Around a hundred houses were evacuated in the middle of the night as five helicopters with monsoon buckets struggled to contain flames whipped on by gale force winds. In the South Pacific, during an El Nino, tropical cyclones tend to form further east, and once formed mostly move southeastwards. This increases the cyclone risk for Fiji,Tonga, Niue, and the Southern Cook Islands. For New Zealand, however, the risk of the remains of a tropical cyclone affecting the country is reduced for the same reasons. However, it is as well to remember that, over the long term, El Nino only explains around 20 per cent of the yearly variation of our rainfall and we probably won't get the extremely dry conditions in eastern areas that we saw during the very strong El Nifios of recent memory. There is another factor that could influence our summer. Satellite measurements of the ozone hole over Antarctica showed a record loss of 40 million tonnes of ozone on October 2. Research a few years ago linked the springtime ozone hole in the stratosphere to increased summer westerlies at sea level in the Southern hemisphere (see New Zealand Geographic, Issue 68). Although these stronger westerlies tend to affect latitudes south of New Zealand, it is likely that fronts moving through them will sometimes shift the strong winds over us. Paradoxically, although New Zealand tends to have cooler than average summers during El Nino events, the global average temperature tends to be warmer than average because of the large area of tropical ocean that is warmer than normal and flow on effects such as milder winters over North America. The strong El Nino of 1997-98 helped 1998 become the warmest year on record, although that was pushed very close by 2005. Given the many record temperatures that have already occurred in various regions this year, now that we have an El Nino on board we may have another shot at that macabre record of the hottest year in recorded history.
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Saleyard
One corner of the town of Feilding is a vast expanse of sheep and cattle yards that fills up with livestock twice a week. And the locals wouldn’t have it any other way. The saleyards, which are among the largest in the Southern hemisphere and handle close to a million sheep and 100,000 cattle annually, have been central to the town’s existence and livestock farming in the lower North Island for well over a century.
Birth of a Wetland
When a Katikati landowner allowed the sea to reclaim some low-lying paddocks, aquatic birds, including a number of seldom-seen varieties such as this black stilt, quickly replaced cattle as the dominant animals.
The Disappearance of Campgrounds
The campground, with its simple cabins and grassy paddock for pitching tents and parking caravans, has long been the main venue for unfussy family holidays, enjoyed by both locals and visitors alike—including the Spensleys and Goodwins from the UK, seen here. However, rising property prices are leading to the sale of many campgrounds for development into superior residential estates. Are inexpensive holidays destined for the endangered list?
Slaking the Big Thirst
Auckland is a thirsty city. It has always been that way. Whether water is required for washing the car, watering the garden, taking a shower or just a making a cuppa, Auckland’s demand seems insatiable.
Maori tourism
I landed with every waka in Aotearoa and all iwi embrace me. I am a custom they call manaakitanga. My brother landed in the pockets of the Pakeha. He is an industry they call tourism. My brother and I have been trying to get along ever since.
