New Zealand Geographic and Heritage Expeditions have announced their next partner voyage: an eight-day expedition through the Hauraki Gulf and Bay of Islands with Island Conservation’s Richard Griffiths as the special guest.
A study by the Pacific Islands Forum Fisheries Agency of illegal, unreported and unregulated tuna fishing has found that the problem may not be as bad as was feared. It estimated that between 2017 and 2019, 192,000 tonnes of tuna worth more than US$300 million was caught each year in the Pacific Islands region by people not following fisheries rules—down from 300,000 tonnes in the 2016 estimate. “The assumption that unlicensed fishing is rampant has been proven false,” says Auckland-based fisheries consultant Francisco Blaha, who contributed to the report. Only five percent of the dodgy dealings involved unlicensed fishing boats. Most—89 per cent—involved licensed operators misreporting which fish they caught, or how many.
Blue sharks swim in all the world’s oceans, and a new study reveals surprising stories about their migrations and behaviour. For his doctoral research at the University of Auckland, Riley Elliott carefully attached satellite tags to 15 blue sharks—11 males and four females—in the waters off northeastern New Zealand between 2012 and 2015. With limited funding available for the expensive tags, Elliott turned to community groups and individuals, the sponsors following the animals’ movements online. In some cases, the tag stayed attached for at least a year. One shark travelled more than 14,000 kilometres from New Zealand to the Pacific Islands and Indonesia and back. Another dived to more than 1364 metres below the surface—a record at the time for blue sharks—and a third swam all the way to the equator. “We were all kind of cheering for him,” says Elliott. “The scientific theory is they don’t cross the equator.” One kilometre from the line, as though the shark had sensed it, he turned and swam south. “Unfortunately, he went through a real hotspot of tuna fishing, and we stopped hearing from him.” These long-distance travellers were all males. The tagged females remained in and around New Zealand waters all year round—a surprise, given fisheries data had suggested there were few mature females here. In a shark fairy tale, Elliott tagged a male and a female off Aotea/Great Barrier Island in 2014. The female had fresh mating scars (shark romance is not gentle), and there were young pups close by. In late summer, the male swam north to the tropics, while the female stayed around Northland. The following spring, they reunited—returning to the same spot near Aotea at the same time. Blue sharks are declining almost everywhere, as they’re caught more often than any other shark in longline fisheries. In 2019, surface longline fishers in New Zealand caught almost as many blue sharks as they did southern bluefin, the species they were actually targeting. About three-quarters of the sharks caught were killed and processed for their fins or meat.
The steep underwater walls of Fiordland’s sounds are home to a lush ecosystem of sponges, corals, and algae in camouflage shades of green and brown. Last summer, divers in Te Puaitaha/Breaksea Sound working to control the spread of the invasive seaweed Undaria noticed something unusual: the Cymbastela lamellata sponges dotted all over the cliffs were bleached a bright white. “Once you see one, you just see them everywhere—as far as you can see,” says diver Millie Mannering. It’s the first time sponge bleaching has been observed in New Zealand, affecting millions or even tens of millions of individual animals. It’s likely the result of last summer’s marine heatwave, when ocean temperatures in Fiordland reached up to five degrees warmer than usual. By chance, sponge ecologists Francesca Strano and Valerio Micaroni from Victoria University of Wellington, who study the effects of climate change on sponges, were also on the trip, and were horrified by what they saw. “We were really worried they would all die,” says Strano. But when the pair returned to Fiordland in June to assess the damage, they found that most of the bleached sponges were still alive—even though the symbiotic green algae that live inside them were mostly gone. These algae give the sponges their colour and supply them with extra food. But there were enough algae remaining that the scientists are hopeful that the cooler waters over winter may allow them to regrow, and the sponges to recover.
Dan Burgin was holding the flesh-footed shearwater chick when it vomited a hard white square of plastic—and stinky stomach oil—over Simon Lamb. The two ecologists, from the consultancy Wildlife Management International, were on predator-free Ohinau Island, off the eastern side of the Coromandel Peninsula, collecting data on the shearwater breeding season. They couldn’t help noticing the plastic scattered around the seabird colonies, especially near the shearwaters’ burrows. The rubbish wasn’t jettisoned by humans—Ohinau Island requires a permit to visit—but by the birds themselves. Seabirds perform a vital ecosystem role of bringing nutrients from the ocean to the land. Now, they’re transporting plastic, too. They’re even feeding it to their young. Burgin and Lamb autopsied 11 flesh-footed shearwater chicks they found dead in their burrows or on the ground, and found that they all had plastic in their stomachs. In one decomposing chick, they discovered 114 miscellaneous particles weighing 35 grams: five per cent of the body weight of a chick roughly the size of seagull, or the equivalent of a human swallowing three kilograms of the stuff. “To see plastics having such a tangible impact on this species was very hard-hitting,” says Burgin. “I had a very heavy heart coming off that trip.” Because of the complexity of ocean currents, the plastic could be coming from both local and international sources, he says. “The problem is probably more acute than we’re aware of.”
As this issue went to print, hundreds of kororā had been found washed up dead in separate events along Te Oneroa-a-Tōhē/Ninety Mile Beach and other beaches in the Far North, in what are called penguin wrecks. The Department of Conservation says little blue penguins are dying as a result of the summer’s marine heatwave, which makes it harder for them to find food. Read more at nzgeo.com/penguins
This past summer was a scorcher, not just on land but in the sea, too. In some of New Zealand’s coastal waters, temperatures reached four degrees higher than normal, while in the Bay of Plenty, a marine heatwave began in November and continued into March. Globally, marine heatwaves have bleached coral, flattened kelp forests, changed whales’ behaviour, wiped out fisheries, and allowed invasive species to spread. They can also cause problems for aquaculture, says MetOcean’s João de Souza, director of The Moana Project, which tracks ocean temperatures around New Zealand and forecasts marine heatwaves one week ahead to help companies farming salmon, mussel and oysters to prepare. (A marine heatwave takes place when temperatures reach a certain level above baseline averages for at least five days in a row.) The abnormally toasty conditions were already evident last winter and intensified over summer, de Souza says, the result of both atmospheric and marine conditions working together. Worldwide, the ocean’s average temperature has increased by nearly 1°C in the past century. On top of that, “the Southern Blob”—an Australia-sized patch of overheated water to the east of New Zealand—has lifted sea temperatures even higher for at least the past decade. This summer, the warm air and clear skies brought by La Niña contributed too, making it New Zealand’s most extreme marine heatwave since records began in 1981. The problem is, once-rare events are becoming normal, says Kisei Tanaka from the US National Oceanic and Atmospheric Administration in Hawaii. “What we once considered extreme is not extreme anymore—because it’s happening every year.” In a recent study, Tanaka and his colleagues used two 150-year datasets tracking sea-surface temperatures worldwide. In each place, they identified the hottest month between 1870 and 1919—a once-in-50-year heatwave. By 2014, more than half of the ocean’s surface was hitting or exceeding that threshold. Tanaka’s study showed that in New Zealand, too, marine heat events have significantly increased in frequency since the 1980s. Between 2010 and 2019, more than half of the country’s exclusive economic zone exceeded the historical ‘once-in-50-years’ temperatures during at least six months of every year. For Tanaka, it’s a stark reminder that climate change is not just “waiting for us on the horizon”, he says. “It’s happening now, as we speak, and it has been happening for quite some time.”
The attack is already underway when the researchers find the blue whale. A huge chunk of flesh has been ripped from its nose, its dorsal fin has been bitten off, and teeth rake scratches scar its body. Still, the whale tries to flee from its attackers. About a dozen orcas continue their hunt, and after 20 minutes, the whale is bleeding profusely. The end is near. Three orcas line up to deliver the fatal blow, ramming into its flank and forcing the whale under. One orca noses her way into the behemoth’s mouth and begins to feed on its tongue. Over the next six hours, around 50 killer whales converge on the 20-metre-long carcass for a blubbery feast. This is the first authenticated record of orcas hunting, killing and devouring a blue whale, the largest animal ever to exist on Earth. The encounter was reported by researchers from Australia and the United States, alongside a further two instances of blue whale predation by the same group of orcas. Whale tongue appears to be an orca delicacy, with two of the three hunts featuring individuals targeting it. Different orca groups often specialise in different hunting tactics: the resident orca population in New Zealand is known for stalking stingrays, while some in Antarctica are seal specialists. Orcas off the Baja California coast may also hunt blue whales, with video footage posted to the internet showing attacks—but no kills.
Where do Tamatea/Dusky Sound’s dolphins go? Starting in 2009, researchers spent a decade trying to find out, setting out 178 times in small boats in all seasons to track and identify the sound’s resident bottlenose dolphins—around 120 of them. They found that the animals preferred to hang out in certain parts of the vast waterway, and that they particularly liked Te Puaitaha/Breaksea Sound (the long fiord at the north end of Dusky Sound) and the Bowen Channel (between Resolution and Long Islands). However, from 2016 to 2018, the dolphins began to leave Breaksea Sound. Fiordland may be one of the wildest places in New Zealand, but human presence is increasing. The researchers suspect that increased boat traffic, the depletion of blue cod by recreational fishers, or the spread of the invasive weed undaria in Breaksea Sound could have something to do with the change. As large predators, bottlenose dolphins are a critical part of the Fiordland marine ecosystem. Nearby Doubtful Sound/Patea and Milford Sound/Piopiotahi have special safeguards in place for dolphins, but not Dusky. The researchers suggest a number of options to protect them: extend the boundaries of existing marine reserves to include dolphin hotspots, restrict vessel traffic in those areas, and lower recreation catch limits within the entire sound. These ecosystem-based approaches would be more effective than another suggestion, the creation of a marine mammal sanctuary, says the University of Auckland’s Rochelle Constantine, who was not involved in the paper. “It’s better to look after the whole area so all the marine life is taken into consideration.”
A machine learning algorithm has identified potentially meteorite-rich sites in Antarctica. The icy continent is a mecca for meteorite hunters—the dry, cold environment keeps the rocks in pristine condition, and their dark colour makes them easy to spot against the white landscape. Still, you need a good dose of luck to find a meteorite stranding zone: areas of ice where wind conditions result in a high concentration of space rocks. The algorithm identified 600 stranding zones with more than 80 per cent accuracy. The findings suggest that there are plenty more meteorites yet to be recovered from the ice—including rare Martian specimens.
New Zealand’s largest lake lies atop a sleeping giant: the Taupō supervolcano, which last erupted some 1800 years ago. But new research suggests that residents of the central North Island need to be wary of earthquakes rather than volcanic blasts. Eruptions may be more dangerous, but earthquakes are much more common. “It doesn’t erupt very often,” says Finn Illsley-Kemp, a seismologist at Victoria University of Wellington. Instead, earthquakes—either caused or affected by the volcanic system—occur on timescales that are more likely to occur within a person’s lifetime. Illsley-Kemp points out that seismic activity has affected the region multiple times in the past 150 years, including an earthquake in 1895 estimated at magnitude six. More recently, earthquake swarms during a period of unrest in 2019 ruptured a major sewer pipe. (These were thought to be at the gentler end of Taupō’s seismic spectrum.) Aside from earthquake risks, the research draws on data from different areas of science to try to understand what’s rumbling in Taupō’s belly: a large chamber of magma five to seven kilometres below the surface. “We don’t really understand why sometimes the magma chamber is ready to blow and why sometimes it’s not,” says Illsley-Kemp. Scientists do know it would give warning signs—but because Taupō hasn’t erupted in the modern era, they don’t know exactly what those would be. To help keep a close eye on the volcano, the research team drew up a range of scenarios, including various triggers for an eruption, such as large earthquakes and interactions with smaller volcanoes nearby. For example, says Illsley-Kemp, scientists detected changes in the Taupō volcano triggered by the 2016 Kaikōura earthquake. “In terms of monitoring, we can’t just focus only on what’s happening under the lake,” he says. “We have to look at the wider system.”
Scientists have identified three new bird species from fossil bones unearthed at St Bathans in Central Otago—which was a massive lake 16-19 million years ago. Among the fossil finds is a wingbone so strange it has sat on a shelf, eluding scientific description, since 2008. “We’ve been puzzling over it, trying to work out what on earth it could be,” says Paul Scofield, a palaeontologist at Canterbury Museum who has been part of a team uncovering the fossil treasures at St Bathans for more than 20 years. The team had hoped to find more matching bones to assemble the skeletal jigsaw, but with more than a decade passing since the discovery, it was time to “give it a name and come up with a hypothesis”, says Scofield. Because of its classification-defying features, they have created a new family for this mysterious bird, calling it Zealandornis relictus. The wingbone displays some similarities to those of mousebirds, a type of sparrow-sized bird with a stubby, finch-like beak and a long thin tail. There are just six living mousebird species, all in Africa, but the fossil record shows that mousebirds were once common across Europe and North America. If this bone does belong to a mousebird, it would be the first Australasian example. But there’s another tantalising option. “There’s a possibility … it is the wingbone of a flying kiwi,” says Scofield. “But the problem is, we simply don’t know what the wingbone of flying kiwi would look like.” Without more bones as evidence, scientists can’t say—and the fragmented nature of fossils at St Bathans means that the record may remain incomplete. Equally, this wingbone could be from a bird with no present-day counterpart, says Scofield. “This animal could well be from a missing lineage, a failed experiment in evolution that didn’t lead to a modern species.” The other new species are more familiar: Manuherikia primadividua is a duck. It’s closely related to another fossil duck from the palaeolake, M. lacustrina. But the two ducks were found in different layers, meaning one is older than the other, which is allowing scientists to put other fossil finds into a rough timeline for the first time. “You might think, ‘Oh, it’s just another dead duck,’” says Scofield, “but it’s an important step in building up a picture of how the animals and plants living on this ancient lake changed over time.” The third new bird, Aegotheles zealandivetus, is part of the owlet-nightjar family, a type of small owl-like bird with big eyes and a wide mouth—although this species was a “big, stout-legged thing” quite different from living examples in Australia and New Guinea. It’s the oldest owlet-nightjar fossil uncovered. The finds are the latest remarkable species uncovered from a site that has yielded a giant parrot dubbed Squawkzilla, a tiny kiwi one-third the size of today’s kiwi, and crocodiles that may have spent more time on land than in water. There’s more to come, according to Scofield: “Every trip, we’re still finding new species.”
The handwriting of New Zealand’s most famous author, Katherine Mansfield (1888–1923), was notoriously difficult to decipher, as those who have studied her manuscripts can attest. It was perhaps fortunate, then, that towards the end of her life she came into possession of a typewriter and from then on used it enthusiastically or, depending on her health, had others type up her manuscript drafts. Mansfield’s typewriter was donated to the Alexander Turnbull Library by her long-time companion Ida Baker in 1971 and deposited in 1972 by Mansfield scholar and Turnbull manuscripts librarian Margaret Scott. The latter met Baker (commonly referred to as LM, or Leslie Moore, in Mansfield’s papers) in 1971 on her research travels to England and France as the second recipient of the Katherine Mansfield Fellowship. In her fascinating 2001 memoir, Scott describes how Baker gave her Mansfield’s ‘little Corona typewriter’, which was ‘a very primitive affair but it still worked’. The typewriter had belonged to Mansfield’s husband, John Middleton Murry (1889–1957), who bought it brand new in March 1920 for £15 15s 0d (the equivalent of the cost of a mid-range laptop computer). We do not know exactly when Mansfield began using the Corona on a regular basis, but entries in her notebooks would suggest that it was some time around the middle of 1920. From 1921 until the end of her life, depending on whether she and Murry were together or apart, the typewriter was at her disposal. This probably indicates that Murry gave it to her, as it was among her possessions that went to Baker after Mansfield’s death on 9 January 1923. This popular model of the Corona 3 was one of about 21,000 manufactured as early as January 1920 by the Corona Typewriter Company in the United States. It was small, light and compact, with a carriage that folded over the keyboard so it could be stored in its purpose-made carry case and easily transported. That would have suited Mansfield well; she changed address around eight times during her final two years as she sought relief and a cure for her tuberculosis. Mansfield spent most of her writing life in England and Europe, remaining ambivalent about her connection to her country of birth and upbringing.
In 1975, New Zealand established the world’s first marine reserves, which became the gold standard for marine conservation and environmental outcomes. Half a century later we lag far behind the rest of the world in protecting our marine estate—an approach more similar to Russia and China than states most Kiwis would consider hold similar environmental values. New Zealand has not commited to the United Nations goal of 30% marine protection by 2030 and the Labour government has failed to meet its own goal of 10% protection by 2020. “For decades New Zealand has played an important role in ocean governance, opposing whaling, reducing by-catch and advocating for the elimination of fisheries subsidies,” says Bronwen Golder, a Kiwi, and fellow at the Stanford Center for Ocean Solutions. “So it’s staggering that we’re not more active in protecting the marine environment to ensure its health, productivity and resilience in the face of climate change, pollution and fishing pressure.”
New Zealand Geographic's next reader voyage in collaboration with Heritage Expeditions will explore some of the most remote and rewarding parts of New Zealand, taking in the Subantarctic Islands, Stewart Island and Fiordland over 12 days with acclaimed author, scientist and explorer Professor Tim Flannery as the special guest.
Minister Parker says New Zealand’s largest commercial scallop fishery is in “serious decline”, yet has just permitted dredging on beds protected by a rāhui.
When an asteroid struck Earth 66 million years ago, three-quarters of all species became extinct, including the dinosaurs. This mass extinction triggered a remarkable burst of evolution, with survivors diversifying to fill ecological niches once occupied by dinosaurs. Among the survivors: the ancestors of today’s snakes. But unlike modern snakes, these ancient species were exclusively insect-eaters. Mathematical analysis of modern snakes’ diets allowed researchers to trace changes back through the evolutionary tree. They found that as bird and mammal populations exploded, snake diets expanded beyond bugs to include these warm-blooded vertebrates. This diversification gave rise to the 4000 snake species on Earth today—but none on land in New Zealand.
When humans first reached New Zealand shores, sometime around the late 13th century, they were accompanied by two mammals: kiore (Pacific rats) and kurī (Polynesian dogs). This arrival triggered huge changes to New Zealand’s biodiversity: the extinction of moa, adzebills and Haast’s eagles, among others. Humans and rats usually get the blame—humans because of hunting and fire, rats because of their propensity to eat eggs, chicks and small animals. But what about kurī, the canine companion of Polynesian settlers? Kurī had white fur, and resembled something between a border collie and a fox. Scientists have long assumed that their ecological impact was minimal, because kurī lived alongside humans. Two University of Otago scientists are challenging this dogma. Kurī probably did play a role in the vast ecological changes following Polynesian arrival, they say. “It’s always been a gaping hole when we look at the impacts of humans on island ecosystems, especially in New Zealand,” says palaeoecologist Nic Rawlence, who collaborated with archaeologist Karen Greig to investigate the effect kurī had. “We’ve always assumed it’s been humans and rats. But dogs would actually have a huge impact: they fill a niche as predators of medium-sized animals like kiwi, kākāpō, takahē and ducks.” Aside from hunting wildlife, kurī could have competed with other predators for food, disturbed breeding animals, or introduced new diseases. Rawlence and Greig point to the impact of wild and pet dogs today: packs of feral dogs killing kiwi in Northland, or dogs disturbing colonies of seabirds, forcing them to abandon their nests. Even if kurī stayed close to camp, and were well-fed taonga, “that doesn’t necessarily mean that they didn’t go wild and hunt and have an impact on wildlife”, says Rawlence. Through archaeological evidence, we know that wherever people were, kurī were, too—and people were everywhere. If kurī strayed from human company and went feral—a subject of ongoing debate—the impacts could’ve been even greater. This area of study hasn’t exactly made Rawlence popular, though. “There seems to be this blind spot in New Zealand around the impact humans’ best friend can have on wildlife,” he says. “As you say, ‘Dogs have a big impact’, people tend not to want to know.”
The previous issue of New Zealand Geographic featured a story about rock hounds—people who fossick in rivers looking for interesting specimens. Several readers wrote to say they would have liked to see more of the rocks up close. Photographer Andy Macdonald became a keen rock fossicker himself while working on the story, and made ‘portraits’ of some of his own finds. Clockwise, from top left: the cut section of a botryoidal pounamu which also contains the minerals diopside and serpentine; an orbicular poppy jasper, so named for its texture and colour; unpolished pounamu; grossular garnet; pakohe, or argillite; the blue-tinted pounamu found in the Nelson region. Got thoughts about one of our stories? letters@nzgeographic.co.nz
A colony of icefish (Neopagetopsis ionah) 60 million nests in size swathes the seafloor of Antarctica’s Weddell Sea, researchers have found in an unprecedented discovery. Previously, the largest known icefish colony consisted of 60 nests. The research team was collecting routine seafloor data using a towed camera, and recorded about four to five hours of fish nests. The city-sized colony, which stretches for 240 kilometres, likely plays an important role in the entire Weddell Sea ecosystem. Gravel-bottomed nests dot the seafloor. Nestled within each hollow, pale blue eggs are guarded by an icefish parent. In another unexpected Weddell Sea discovery, researchers from the British Antarctic Survey drilled through an ice shelf to find an oasis of life that has persisted for thousands of years. Located several kilometres from the open ocean, in an environment characterised by darkness, extreme cold and lack of food, the 77 different species recorded included tube-building worms and bryozoans—also known as moss animals and sea mats.
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