Rakiura's western shoreline is the flotsam-and-jetsam coast. Here the detritus of human endeavour mingles with nature's dead—albatrosses, whales, kelp, fish. It is the dune coast, too, where a beachcomber can follow kiwi tracks through hillocks of sand or pause to watch a wolf spider transporting her young. It is a place apart.
This summer will be remembered by many for the large numbers of stinging bluebottles (Portuguese man-of-war jellyfish) that appeared in the surf and on the shores of many New Zealand beaches. At the height of the Christmas–New Year holiday break the media ran hot with stories of swarms of abnormally large bluebottles. Reports came from as far south as Otago, although the most spectacular accumulations were seen further north. Thousands washed ashore along the upper west coast of the North Island, having been blown landwards by persistent summer winds. With eight centimetre floats (more than twice the size of normal bluebottles) and tentacles approaching two metres in length, these big jellies were described in newspaper and television reports as a rare and distinct species, the "Pacific man-of-war." Their sudden appearance in the shallows off popular swimming beaches soon exacted a significant human toll, with many dozens of stings reported from the Auckland west coast. The stings were severe by New Zealand standards, often affecting the whole body rather than just a localised patch of skin. In one case a man was rushed to Auckland Hospital with breathing problems, apparently due to an allergic reaction. Symptoms reported in other cases included chest and stomach cramping, swelling and the inevitable welts where skin had come into contact with tentacles. Peter Fenner, an Australian physician and researcher on the clinical aspects of jellyfish envenomations, advised against the traditional remedy of applying vinegar to the affected area. Acid can make things worse by causing even more of the bluebottle's stings to be discharged, he said. Instead, he recommended pouring cold, fresh water on to the stung flesh and applying an ice pack. Were the jellyfish involved in these incidents a new species in New Zealand's seas? Phil Pugh, an English expert on world siphonophore jellies (of which the bluebottle is one), thinks not. He believes there is only a single worldwide bluebottle species, Physalia physalis, but that it varies greatly in size. The "Piha monsters" of this summer past are small fry compared to tropical Atlantic specimens, whose floats reach 25 centimetres across and whose wafting tentacles can be up to 20 metres long. Deaths have been recorded in the northern hemisphere from contact with these giants, though probably due to allergic reactions rather than the toxic effects of the venom itself. Of course, bluebottle tentacles and stings are not designed merely to inflict human misery. Like other jellyfish, bluebottles are predators. On contact with their prey—plankton and fish—bluebottle tentacles discharge thousands of microscopic poison-tipped harpoons called nematocysts. The strength of the poison varies with the species. Bluebottle venom is powerful, capable of paralysing fish as large as the jellyfish itself. The nematocysts are used only once—after discharge they are digested along with the prey they helped kill. Bluebottles are not true jellyfish, although they do belong to the same animal phylum, the Cnidaria, along with sea anemones and corals. They belong to a group called siphonophores, an order of marine gelatinous animals in which each individual is actually a colony of genetically identical, highly specialised animals. The individual units of a siphonophore colony—the zooids—are highly modified for particular tasks: catching food, digestion, swimming or reproduction. Deep-water siphonophores specialise in catching fish larvae and crustaceans, and their colonies can reach enormous sizes. One species found in New Zealand's deep sea, Praya dubia, is known to reach lengths of 60 metres—more than half the length of a football field. Its colonies, which are far too delicate to survive the violence of coastal waters, resemble a never-ending string of Christmas tree lights and have only ever been seen intact through the viewports of deep-diving submersibles. Fortunately for New Zealand swimmers, our waters lack the most dangerous jellies: sea wasps or box jellyfish, seasonal residents of large tracts of the tropical Indo-Pacific including northern Australia. The toxin of these transparent jellyfish is extremely virulent, and fatal stings are not uncommon. Death can occur in as little as three minutes after a severe attack. Because of the swiftness of the envenomation, it is often difficult to get the patient to a medical facility in time to administer first aid—a problem which contributes to the high death rate. Sea wasps aren't the only dangerous Australian species. Earlier in the 2001-2002 summer, the potent stings of another jellyfish, the irukandji, hospitalised 80 people in Cairns alone. Not all jellies are nasty. Many species lack the stinging power needed to ruin a day at the beach or even to elicit symptoms. Most of the small to minute jellyfish known as hydromedusae are relatively harmless to humans, although one species found in the northern North Island causes an itchy rash known medically as "sea-bathers eruption." Bluebottles pose a much more significant hazard to New Zealand bathers and beachgoers, for they can sting long after washing ashore. Their tentacles are surprisingly strong and elastic, and have an uncanny ability to wrap themselves around arms or legs, even on the slightest contact. Yet jellyfish, for all the anguish they can cause, are ephemeral creatures, and those encountered in the surf and on the sand are within hours of death, destined to become windblown papery husks. The painful memories of thousands of beachgoing New Zealanders will far outlast the agents that caused their misery.
After more than four decades of operation, New Zealand's Antarctic research station, Scott Base, is installing a sewage treatment plant. Scott Base houses around 80 scientists and staff during summer, and a crew of 10 during the winter. It consists of a complex of lime-green buildings which open on to the frozen continent through fridge-style doors. The base is set on crunchy black volcanic gravel at the tip of Ross Island's Hut Point Peninsula and is surrounded for most of the year by sea ice. For the past 45 years, the biological wastes from the base have simply been macerated and discharged into the sea under the ice near the shore. Scott Base discharges up to 17,000 litres of this raw sewage and wastewater daily, while neighbouring US McMurdo Station discharges up to 270,000 litres. Changing attitudes mean that crude discharge is no longer acceptable. Italy included a treatment plant in its new base constructed in 1987. And now, after the adoption of the 1991 Protocol on Environmental Protection to the Antarctic Treaty and the restructuring of Antarctica New Zealand in 1996, the Scott Base sewage question is being addressed. As part of the project justification process, expert monitoring teams were flown to Scott Base to investigate the fate of the discharged sewage and sediment in the environment. The job was difficult—like trying to observe the condition on a rugby pitch with the rain covers on, except it was a lot colder. Researchers drilled holes through the 2 m-thick sea ice, then tried to plot the movement of currents carrying the wastewater and also to sample seafloor organisms for signs of sewage assimilation. They concluded that the effect of the discharge was almost undetectable beyond 50-60 m from shore, but that there was a cumulative effect on inshore communities. A second concern was for human health. The clash of shelf and sea ice at land's edge causes pressure ridges of ice to form, and some of these ground in shallow water. The ridges impound discharged effluent, keeping it close to the base's drinking water intake pipe. A third concern was about consequences of possible introduction of foreign genetic material into local organisms. Some scientists believe that seals near McMurdo Sound are being infected by the human enteric bacterium Clostridium perfringens during summer. Infection of invertebrates in the area could lead to the transfer of human bacteria to other marine life as well. The Antarctic seawater remains at around –1.8° C throughout the year. At this temperature, anthropogenic organic matter decomposes a third as quickly as at 20° C. Organisms such as Clostridium perfringens are able to persist in these conditions, even surviving beneath 5 cm of sediment, suggesting that at least elements of the sewage may persist for a long time. Several other issues were also considered, in the areas of human health, environmental contamination, environmental dynamics and ethical and moral issues. In view of the fact little is known of the effects (both immediate and cumulative) of exposing Antarctic marine environments to human pathogens, the precautionary principle was adopted and the decision made to spend almost $500,000 on a treatment plant. The final environmental assessment report cited the need to reduce the disposal of wastes as far as practicable, in order to minimise the impact on the Antarctic environment, and to reduce or remove pathogens as a precautionary measure. "But in the end," says Emma Waterhouse, environmental manager of the New Zealand Antarctic Institute, "there was a large ethical component to the decision. There is no longer any reason for New Zealand to be making these discharges. We want to be leading by example." The selection of the most suitable sewage plant for the base was a complex process involving consideration of treatment performance, maintenance needs, environmental "footprint," logistics and cost. Among the design challenges, extreme cold was not a major problem, as the plant is to be housed inside a building heated partially by the temperature of the waste itself and partially by recycled warm air. Several types of plant were considered. Some, such as composting or high-pH systems, were rejected as they would require bulk shipments of sawdust or lime to Scott Base. Another system was rejected because it required a 7 m-high building, which was considered to have too great a visual impact on the landscape. Finally, a fixed-bed aeration process with UV disinfection was chosen. This system must cope with several inherent features of the base wastewater: the high salinity of the seawater flowing through the flush toilet system, (water produced by reverse osmosis—used for drinking—is too "energetically expensive" to use in toilets) and the fluctuation in numbers of people on base. With the decrease from up to 100 summer personnel to 10 in winter, the system will have parts of its surface area phased in and out of action. In other seasonally run systems, such as skifields, the sudden decline in nutrients is remedied by feeding the system dog food to keep the bacteria thriving. After filtering and UV treatment, the water will be piped into the bay, while solid sludge will be dewatered to 20 per cent dry solids (the consistency of moist cake) and returned to New Zealand for disposal. An estimated 5.5 tonnes will 0 enter the Christchurch City wastewater treatment plant each year. The foundations for the new plant have been laid and the parts shipped to Ross Island in several containers, all pre-prepared for erection on site. The plant will be phased in over the coming winter, when only a few personnel are present. Waste disposal of any sort is a serious matter in Antarctica. Chefs at Scott Base, cognisant of the fact that a cosmopolitan poultry virus has reached and infected Antarctic birdlife, are careful to collect all water dripping from thawing chickens for return to New Zealand. Field researchers who camp out are required to collect their waste and return it to base. The United States' Amundsen–Scott South Pole Station is too far from anywhere to freight out waste. It simply creates chasms in the ice to be filled with waste. These are calculated to reach the oceans below on geological, rather than human, timescales. But for Scott Base the news is good. By next season, New Zealanders working at the base will be able to relax when they spend a penny, confident their waste is not going to damage the fragile Antarctic environment.
In the last week of December 2001, smoke from the New South Wales bushfires drifted across the Tasman Sea and spread over parts of the North Island. Atmospheric visibility around Auckland, usually 40 km or more, fell to below 10 km. By day the smoke appeared as a milky blue haze because all the large particles of ash had fallen to the earth close to the fires, leaving only the smallest particles suspended in the air. The reds and yellows of sunrise and sunset were enhanced and lasted longer, with shades of brown added in. The moon, in particular, appeared yellowy red instead of its usual silver colour. The arrival of the smoke is a reminder that although Australia seems a long way away, the wind is capable of carrying many things across the 2000 km that separates us from our neighbour. Microscopic mineral particles from Australian dust storms have been found on the snowfields of the Southern Alps. Pollen from Australian trees has been found in New Zealand peat swamps. Fungal spores must have crossed the Tasman on the wind, as outbreaks of wheat rust and poplar rust in New Zealand have followed a couple of months after outbreaks in Australia. Insects have also made the trip. Australian butterflies have turned up here (to say nothing of several Australian bird species that have established in this country) and an invasion of grain aphids in Canterbury followed a very severe outbreak in Victoria in 1967. Westerly winds are clearly part of the meteoro logical recipe that brings all these gifts—wanted or not—across the sea. A lifting mechanism is also needed at the Australian end to loft the hitchhikers up off the ground. One of these mechanisms is likely to be the updraughts known as thermals that arise because of the way dark surfaces heat up faster in the sun than pale surfaces. The air over a dark surface, such as asphalt, is heated more than adjacent air over a lighter surface, such as grass. The wanner air is less dense, so it rises up through the cooler air like a giant bubble, carrying its cargo of dust, pollen and insects with it. Other lifting mechanisms include turbulence associated with strong winds and the lifting of warm air by cold air in frontal processes. A free ride on the breeze can be short-lived if there is rain about. The best clear skies always come after heavy rain has washed the sky clean of dust and haze particles. In fact, heavy burdens of dust can colour the rain red and splatter surfaces with mud. Large amounts of pollen have caused yellow rain in some places. Rain also knocks down insects very rapidly, and hailstones have been found with insects encased within them. Once across the Tasman, the riders on the wind need a way to get down to the surface. Rain may indeed do the job for dust and pollen, but insects need a dry staircase from heaven if they are to survive. Large eddies caused by the westerlies humping into our mountains seem to facilitate descent, and it is possible that some insects actually fold their wings and dive once they sense they are over land. Some insects, instead of risking the hazards of riding the wind, take the safer option of hitchhiking on aircraft. This seems to have been the case with a nest of red imported fire ants (RIFA) found at Auckland Airport in March 2001. Fire ants are an unwelcome visitor to this country. Not only are the individual ants capable of delivering a nasty sting, similar to that of a bee or wasp, but also the colony swarms if disturbed. So if you bump into a nest you are likely to be stung not just once, but dozens or hundreds of times. Fire ants feed on insects and birds' eggs and can kill small animals such as lizards. They are also very aggressive competitors, and might be capable of overwhelming and replacing the existing ant species in New Zealand, none of which sting or exhibit swarming behaviour. RIFA originate in the swampy Pantanal area of Brazil, Paraguay and Argentina. They have been established in parts of the southern United States for decades, where they have a track record of destroying electrical wiring, eating seeds and damaging fruit crops. The state of Texas alone spends $US200 million a year on control measures. RIFA have recently secured a foothold in Australia, with more than 700 nests being found in 36 Brisbane suburbs. One family had 47 nests in their backyard. According to Keith McCubbin, director of Queensland's Fire Ant Control Centre, the ants will attack anything that's on the ground. He describes RIFA as "the pest from hell" and says the ants could completely change the way Australians use the outdoors. Thongs (jandals), for example, could become a thing of the past. A fund of $A123 million has been set up to try to eradicate the ants. It is estimated that without control they could spread over 600,000 sq. km in 30 years, causing more than $A6 billion in damage. The good news for New Zealand is that we may have got to the recent fire ant arrival in time. Once the ants were discovered—by a gardener mowing the lawn—the Ministry of Agriculture and Forestry (MAF) destroyed the nest. From the number and size of the dead ants MAF was able to deduce that the nest was likely to have been in the ground for between nine months and two years—time enough for it to have matured and sent out mated queens to start new colonies. So MAF Biosecurity meticulously searched an area within a 500 m radius of the nest. No more fire ants were found although over 1000 nests of endemic ants were found in the area. Bait traps were also laid in the area, as well as at all garden centres within a 5 km radius and at places shipping containers were unloaded. These measures covered ants walking away from the colony, as well as any hitching a lift on a local vehicle. That left the problem of aerial dispersal. Here MAF called on the expertise of atmospheric modeller Richard Turner and his colleagues from the National Institute of Water and Atmospheric Research (NIWA). From overseas research it was known that the environmental conditions necessary for mated queens to fly off were temperatures exceeding 24°C, with relatively light winds after a rainy and damp period of 48 hours. The days when these conditions had been met were identified from a climate database. Then, for each of these days, a fine-scale computer model of the lower atmosphere was run to determine the flight paths of any queen ants that took off on those days. The ants are poor fliers, and essentially go where the wind takes them. Once the areas at risk were identified, MAF Biosecurity distributed fact sheets to all households within those areas, describing the appearance of the ants and their nests. (The fact sheet and other information about the ants can be found on the MAF website www.malgovt.nz/fire-ants). A mail drop had already been undertaken to all households within 5 km of the nest. In all, around 100,000 fact sheets were distributed, not just to households but also nationwide to doctors, veterinarians, pest-control operators and various other groups. "We can never have enough eyes on the ground,"says Amelia Pascoe, MAF's programme coordinator. The government has allocated $NZ 1.1 million to fund ongoing surveillance for RIFA in the areas at risk near Auckland Airport as well as at other international ports of entry. So far this summer MAF has found no new nests, but surveillance will need to continue for 24 months before this invasion can be declared over. In that time, of course, more ants, or other insect pests, may have caught a ride on an aircraft or on the wind to get here. Next time you step out for a breath of fresh air, spare a thought for the fact that you are welcoming into your lungs a small stretch of an insect highway.
In a land renowned for its unusual birds, the kākāpō—a giant flightless nocturnal parrot with a bizarre breeding system—has to be one of the strangest. Although it has been lingering perilously close to extinction for the past half century, there is renewed hope that this icon of conservation effort has a future after all.
Infamy in the heart of the Amazon.
Granite citadels stud the seaward face of the Ruggedy Mountains, in north-west Rakiura/Stewart Island, an area as grand and remote as any in the country. Almost all of New Zealand's third island is wilderness—unbroken swathes of forest or shrubland which run from summit to coast. In recognition of its unspoiled landscapes and biological uniqueness, most of the island is being preserved as a national park—a development many islanders view with mixed feelings.
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