South Africa's Invasive Species Guzzle Water and Cost US$450 Million a Year

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suggested that a federal appeals court its own copycats — some of which have policies at issue, and that the rights to life, should consider the administration’s argu- progressed further than Juliana itself. “It is a liberty and property set out in the Constitu- ments before any trial starts in the Oregon global phenomenon,” Lobo says. tion translate into the right to a stable climate. district court. Lawyers for the young people One case modelled on the Juliana lawsuit In any case, the department argues, no mean- said that they would push the district court to has already produced a striking victory. In ingful redress is possible, given that sharp cuts reschedule the trial this week. January, 25 young people sued the Colombian in US emissions might not move the needle “The youth of our nation won an important government for their right to a healthy envi- on climate change much if other countries’ decision today from the Supreme Court that ronment, in a case called Demanda Genera- greenhouse-gas output grows. shows even the most powerful government in ciones Futuras v. Minambiente. Andrea Rodgers, co-counsel for the Juliana the world must follow the rules and process of The Colombian Supreme Court found in plaintiffs, says that the Trump administration litigation in our democracy,” said Julia Olson, the plaintiffs’ favour hasn’t challenged the fact that humans are co-counsel for the plaintiffs, in a statement. in April. Not only did “We need to changing the climate. “They haven’t presented Although climate change is a global problem, it order the govern- win as soon as experts to contest what our scientists are say- lawyers around the world have brought cli- ment to take steps to possible. But if ing about ice melt or sea-level rise or terres- mate-change-related lawsuits against local and reduce deforestation we lose, we don’t trial impacts or how climate change happens national governments and corporations since and climate change, give up — we or ocean acidification,” she says. the late 1980s. These suits have generally sought it also ruled that the come back with a To win, Rodgers says, “we have to show that to force the sort of aggressive action against cli- Colombian Amazon stronger case.” the United States government is liable, but also mate change that has been tough to achieve rainforest is “a subject that there is a remedy that the judge can order”. through political means. of rights” that is entitled to “protection, conser- The United States has seen its greenhouse-gas Many of the cases have failed, but in 2015, vation, maintenance and restoration”. emissions drop in recent years, as the coun- a citizen’s group called the Urgenda Founda- The young plaintiffs in the Juliana case try shifts its energy mix away from coal and tion won a historic victory against the Dutch allege that they have already suffered harm towards renewable sources, but as of 2016, it government. The judge in that case ordered from climate change. Seventeen-year-old remains the second-largest emitter after China. the Netherlands to cut its greenhouse-gas Jaime and her family left their home on the James Hansen, a climatologist at Columbia emissions to at least 25% below 1990 levels by Navajo Nation Reservation in Cameron, Ari- University in New York City and a long-time 2020, citing the possibility of climate-related zona, in 2011 because the springs that supplied climate activist, is an expert witness in the case damages to “current and future generations their water were drying up. Fifteen-year-old — and a plaintiff, representing “future genera- of Dutch nationals” and the government’s Jayden’s home in Louisiana was severely dam- tions” not yet born. (His 20-year-old grand- “duty of care … to prevent hazardous climate aged by flooding in 2016, and 19-year-old Vic’s daughter Sophie Kivlehan is also a plaintiff.) change”. A Dutch appeals court upheld the school in White Plains, New York, closed tem- Hansen has been fighting for action on verdict last month. porarily in 2012 after Hurricane Sandy hit. climate change since he first testified on the Over the past few years, the Dutch case US climate hawks hope that the Juliana subject before the US Senate in 1988. He says has emerged as a model for climate lawsuits plaintiffs will ultimately prevail, but President that if the Juliana plaintiffs lose their case, he in other countries, says Gillian Lobo, a law- Trump’s administration is mounting a mul- will simply try another way. “We need to win yer who specializes in climate-change-related tipronged defence. The Justice Department as soon as possible,” Hansen says, “but if we cases at ClientEarth in London. More recently, denies that the district court in Oregon has lose, we don’t give up — we come back with a she says, the Juliana lawsuit has inspired jurisdiction over the broad sweep of federal stronger case.” ■

ECOLOGY South Africa’s invasive species guzzle water and cost US$450 million a year The country’s first report on its biological invaders is pioneering in scope, and paints a dire picture for resources and biodiversity.

BY SARAH WILD Biodiversity Institute in Pretoria released on This achievement constitutes a “significant 2 November. advance” compared with efforts by most other outh Africa is losing its battle against Invasive species also guzzle water, a countries, says Piero Genovesi, who chairs the biological invaders, according to the gov- serious problem in a country suffering from invasive species specialist group of the Inter- ernment’s first attempt to comprehensively a prolonged and catastrophic drought that is national Union for Conservation of Nature in Sassess the status of the country’s alien species. expected to worsen as the climate changes. Rome. He says that other reports have looked The invaders, including forest-munching The report, which the institute compiled at the impact of biological invasions, or at wasps and hardy North American bass, cost the in response to 2014 regulations that mandate measures to address the problem, but have not country around 6.5 billion rand (US$450 mil- a review of invasive species every three years, considered all aspects of invasions. lion) a year and are responsible for about examines the pathways by which these species The report provides “an incredible basis” on one-quarter of its biodiversity loss. That’s the enter the country and the effectiveness of inter- which to deal with invasive species in South conclusion of a pioneering report (see go.nature. ventions. It also weighs the toll they take on the Africa, says Helen Roy, an ecologist at the Cen- com/2qmwgag) that the South African National nation’s finances and biodiversity. tre for Ecology and Hydrology near Oxford, UK.

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ENVIRONMENT Australia cuts coral research Reef-science centre set to lose government funding.

BY ADAM MORTON

cean researchers around the world are dismayed that an Australian research institute that has become Oan international authority on the declining health of reef ecosystems will lose most of its government funding after 2021. Papers by scientists at the Centre of Excellence for Coral Reef Studies, based at James Cook University in Townsville, were cited almost 40,000 times in 2017 — the most citations for any institute in the world doing reef science. But in late The invasive ant Linepithema humile disrupts seed dispersal in indigenous South African plants. October, it emerged that the Australian Research Council (ARC), an independent Across the world, invasive species — Linepithema humile, from Argentina, which government agency, had not shortlisted the organisms that have been introduced into disrupts seed dispersal in indigenous plants; centre to receive a share of the latest round ecosystems beyond their natural habitats, and the North American small-mouth bass of funding. The ARC has funded the centre that spread over large distances on their own (Micropterus dolomieu), which has outcom- since its inception 13 years ago. — are considered a major threat to biodiversity, peted indigenous fish; and the water hyacinth The centre will lose 37% of its current human health and economies. Climate change (Eichhornia crassipes), from South America, annual budget of about Aus$12 million is expected to further their global spread, in part which chokes the country’s waterways. (US$8.7 million), and its title as an ARC by reducing the resilience of native ecosystems. As well as their cost and toll on biodiversity, centre of excellence. James Cook University To create the report, in 2015, 37 research- the report explores the pressure that invasive says it is committed to delivering world-class ers from 14 national organizations, led by the species put on the water supply. This year, coral-reef research into the future, but has MARK MOFFETT/MINDEN PICTURES/ALAMY MARK MOFFETT/MINDEN National Biodiversity Institute and the Centre Cape Town almost became the first major not explained how the centre will be sup- of Excellence for Invasion Biology at Stellen- city in the world to run out of water. In May, ported. The centre’s director, Terry Hughes, bosch University, began collating data from researchers argued that alien plants, which declined to comment on the decision. institutions around the country. often use more water than do indigenous ones, Scientists fear job losses and a reduced consumed more than 100 million litres of research capacity are to come. They say MAJOR IMPACTS water a day — about one-fifth of the city’s daily the centre’s work is important to people The researchers report that 7 new species are usage — and that water losses due to invasive living alongside reefs across the tropics. “It introduced into South Africa each year, and species could triple by 2050. The report esti- is deeply stupid for Australia not to fund, that about 775 invasive species have been mates that invasive trees and shrubs, if left or even consider funding, its world-leading introduced so far. This contrasts with the unchecked, could threaten up to one-third of coral-reef research,” says Garry Peterson, an 556 invasive species previously reported by the water supply to cities such as Cape Town, environmental scientist at the Stockholm the government. Most of the species identi- and consume up to 5% of the country’s mean Resilience Centre. fied by the latest report are plants, with insects annual rainfall run-off. The coral-reef centre employs about the next most common. (For comparison, Despite enacting the 2014 regulations and 300 scientists. Its most celebrated work, the United Kingdom says that it has 184 non- spending at least 1.5 billion rand a year to curb which established the extent of recent native invasive species.) The report’s authors invasive species, the country is not keeping up, bleaching along the Great Barrier Reef consider 107 of the species in South Africa to says the report. “The most concerning find- (T. P. Hughes et al. Nature 543, 373–377; have major impacts on biodiversity or human ing was how ineffective we have been,” says co- 2017), involved aerial surveys and 100 divers. well-being. author Brian van Wilgen, an applied ecologist Some researchers link the ARC’s decision Invaders of note include trees in the Prosopis at Stellenbosch University. to the Australian government’s failure to genus, such as honey mesquite (P. glandulosa), But the authors also note that their con- adequately address climate change, which is which damages animal grazing areas, out- fidence in almost all their estimates is low, the greatest threat to coral reefs. “A different competes local plants and, according to a because of poor monitoring and evaluation government with a different outlook would 2017 study in Mali, seems to encourage the data — and that more research into impacts have found a way to support that centre,” growth of populations of the malaria-carry- and monitoring techniques is needed. says physicist Bill Hare, chief executive of ing Anopheles mosquito, among other effects Jasper Slingsby, an ecologist with the South the climate-research and policy institute (G. C. Muller et al. Malar. J. 16, 237; 2017). African Environmental Observation Network Climate Analytics in Berlin. Others include the Sirex wasp (Sirex in Cape Town, agrees. “We need better funding But ARC chief executive Sue Thomas noctilio), which threatens South Africa’s and concerted research effort in this space as a says that the decision was based on a 16-billion-rand forestry industry; the ant national priority,” he says. ■ standard competitive process. ■