Ecology

Hammerhead sharks (Sphyrna mokarran) are critically endangered and would benefit from conservation efforts.Credit: Alex Mustard/Nature Picture Library

Disputes over how to finance conservation of the world’s plants and animals have resurfaced between countries — threatening their ability to meet goals laid out in a historic plan signed late last year, sources have told Nature.At the COP15 biodiversity summit in Canada in December, more than 190 countries agreed to the Kunming-Montreal Global Biodiversity Framework, a deal including targets such as nations protecting and restoring 30% of the world’s land and seas by 2030. To ensure that all countries — particularly low- and middle-income nations (LMICs) — can meet these targets, those that signed the deal agreed to establish a trust fund by the end of this year and that, by 2030, wealthy nations should collectively be contributing US$30 billion per year.Several times during those negotiations, however, arguments erupted and threatened to derail the deal. The disputes are now rearing their heads again.A showdown loomsDuring COP15, LMICs that are rich in biodiversity called for a new, independent fund for species conservation. The current fund, run by the Global Environment Facility (GEF) within the World Bank in Washington DC, is difficult to access and slow to distribute funds, LMIC representatives said.
Nations forge historic deal to save species: what’s in it and what’s missing
But high-income nations, including some of those in the European Union, disagreed, and eventually it was decided that a newly established fund would be run by the GEF — although the deal set out provisions to continue discussions about an independent biodiversity fund.With the approach of a 26–29 June meeting, at which the GEF is set to start the process of establishing the biodiversity trust fund, fissures have appeared that threaten to delay the proceedings, according to sources involved in the discussions, who asked not to be named to maintain diplomacy.At the upcoming meeting, GEF council members — including representatives from 14 high-income countries and 18 LMICs — are slated to review a proposal, posted to the GEF’s website, to establish the fund with at total of at least $200 million from at least three donors by December. But sources say that donor countries are reluctant to agree on any initial budget for the GEF, preferring to set up the trust fund first and then discuss funding pledges. LMICs, on the other hand, say that the initial amount proposed is not enough. Researchers have suggested that the amount needed to fully safeguard and restore nature is approximately $700 billion.
Can the world save a million species from extinction?
Brian O’Donnell, the director of Campaign for Nature, a conservation advocacy group based in Durango, Colorado, says that the success of the framework depends on donor countries making good on their pledges to increase biodiversity funding. In addition to agreeing to contribute $30 billion annually by 2030, wealthy countries said that they would help to find $200 billion per year from private and public sources by 2030. But the countries have not yet started to deliver on these promises.“We need real money from donor countries,” O’Donnell says.In a statement to Nature, a GEF spokesperson said that the facility is “optimistic” that the June council meeting will approve the trust fund, and declined to comment on ongoing disputes.Biodiversity delaysLMICs are keen to see whether establishing the trust fund in the GEF is a “genuine” move by donor countries to avoid the logistics and costs of an independent fund, allowing for faster money transfer, as they stated during COP15 negotiations, says Paul Matiku, executive director of Nature Kenya, a conservation organization in Nairobi.
Scientists warn deal to save biodiversity is in jeopardy
Daniel Mukubi, a negotiator of the biodiversity-framework deal for the Democratic Republic of the Congo (DRC) who is based in Kinshasa, told Nature that some nations are not happy and are holding out for an independent fund. LMICs don’t have an adequate say in how the GEF funds are spent, he says. The DRC and other LMICs will not agree to the trust fund until after discussions on an independent fund, he adds. “We will not give up.”These tensions could delay the trust fund’s adoption, which was planned for a GEF assembly in August, delaying biodiversity action even more — as it is, the Kunming-Montreal framework was agreed two years late, owing to the COVID-19 pandemic. Meanwhile, the clock is ticking: researchers have estimated that one million species are under threat of habitat loss because of factors such as climate change and agriculture. More

I’m Guardian of the Pipmuakan forest in the Nitassinan territory of Quebec, Canada. I act as the eyes and ears of my people, the Innu, so that we can protect the caribou (atik in the Innu language). The caribou, or reindeer (Rangifer tarandus), is sacred to the Innu. For centuries, it provided us with food, clothes and tools.In my work, I combine ancestral knowledge with new technologies. The knowledge includes how to assess the ice thickness and snow depth, and how to identify the freshness of animal tracks. Drones, satellite images and GPS are among the new technologies I use.I travel across the Pipmuakan area at least four days a week on either my quad bike or snowmobile, looking for caribou tracks and other signs of herds and their predators. I also set traps for wolves.Caribou are very sensitive, so I always avoid getting close to them. When I see new caribou tracks, I use the drone to identify their location and confirm the number of animals in the herd, whether they are male, female or both, and if there are new calves. The drone also allows me to spot herds behind dense thickets without scaring them.Logging is the main threat to this forest and to the caribou. In winter, caribou eat lichen from trees. But logging destroys the lichen, and allows wolves — the caribou’s main predator — to see their prey from afar.In this picture from the third quarter of last year, I was crossing Kakuskanus lake in a pontoon boat to reach a remote area of the forest. My grandparents drowned in this lake when their canoe overturned. For 36 years, I couldn’t visit this place. I was mourning.But in 2017 I felt an urge to protect the land and came back. A century ago, there were thousands of caribou here. Now there are fewer than 200. Without the caribou, the Innu wouldn’t have survived in this forest. Now it’s time for us to help the caribou. I want my grandchildren and the following generations to experience the richness of this forest. More

The first African cheetah introduced to India last September gazes at its new home.Credit: Press Information Bureau/PIB Photo/Alamy

The world’s first intercontinental cheetah-introduction programme hit a setback last month when it emerged that three relocated animals, and three of their cubs, had died in the space of eight months. The scientists and officials behind the 500-million-rupee (US$6 million) conservation project, which was launched with great fanfare and the support of Indian Prime Minister Narendra Modi, say they will carry on with the project. But several independent scientists question whether this is wise and the project’s long-term viability.They expressed concern that the space reserved in India for the cheetahs is too small for the intended population, and they are not sure that enough has been done to prepare or to investigate how nearby farming communities will react to the animals. “With everything we know about cheetahs in this world, it seems a bit like hit-and-miss,” says Florian Weise, an independent wildlife biologist in Berlin, Germany who relocated cheetahs between different parks in Namibia for eight years.A goal of Project Cheetah is to help conserve the vulnerable South African cheetah (Acinonyx jubatus jubatus). Only 6,517 cheetahs remain in the wild, according to the International Union for the Conservation of Nature. Cheetah populations have rebounded in semi-managed reserves in South Africa (these animals are not included in the ‘wild’ number), but conservationists say there is not enough safe, wild habitat there for them to expand into. The India project is an attempt to solve this problem. The country once hosted its own population of the Asiatic subspecies (A. jubatus venaticus), which is now critically endangered and present only in Iran.Project Cheetah officially launched last September, when 8 African cheetahs were relocated from Namibia to India; 12 more were then moved from South Africa in February. Project officers released seven into Kuno National Park, an unfenced 748-square-kilometre area that was once home to cheetahs and is now inhabited by leopards (Panthera pardus).But by late May, three of the Kuno cheetahs and three newborn cubs were dead.The deaths of the three adult cheetahs were not unexpected given the high stress of relocation, says Adrian Tordiffe, a veterinarian at the University of Pretoria in South Africa, and a consultant for India’s Project Cheetah. Indeed, the Project Cheetah action plan notes that only 50% of the animals are expected to survive. “The fact that we had multiple deaths occurring in a short space of time is not unusual in the sense that it’s the high-risk period,” Tordiffe says. “Once things stabilize, that will plateau.”Two died of organ failure, and a third died in a violent mating encounter.But the deaths of the cheetah cubs are more puzzling, says Bettina Wachter, a biologist at the Cheetah Research Project, based in Berlin. Cheetah cubs in places such as the Serengeti have only a 10% survival rate owing to predation from lions (Panthera leo) and spotted hyenas (Crocuta crocuta). But in protected reserves in Namibia, where there are few predators, their survival rate is 80%, she says. She adds that, in Kuno, which has few predators, she would expect a higher survival rate.Tordiffe was also surprised by the deaths: “I wasn’t expecting these cubs to succumb given the sort of circumstances in which they were being kept,” he says.The Madhya Pradesh forest department, which manages Kuno and is implementing Project Cheetah, said the cubs died of malnutrition and weakness.Too hastyWachter and other scientists worry that Project Cheetah was drawn up hastily, without enough preparation. Only nine months elapsed between the release of the action plan and the first animals being moved to India.But Tordiffe says it made sense to act rapidly while there was political momentum. “When you have the political will, the financial backing and the financial support for a project like this, then you do everything that you can to try and make it happen, even in a short time frame,” he says.In particular, there is debate over whether Kuno is big enough for the big cats.Cheetahs need a lot of space, even compared with larger predators such as lions and tigers (Panthera tigris). Wachter says that male cheetahs maintain a 20- to 23-kilometre distance between their territories in unfenced parks in eastern and southern Africa. This separation reduces competition — and it seems to be consistent across the species, no matter the location, she says. Given these dynamics, she calculates that Kuno can house at most eight cheetahs — five males and three females.The Project Cheetah action plan says that, with the large amount of prey at the park, it can hold 21 cheetahs.“But there is really no evidence anywhere in the world that cheetahs squeeze together when there is more prey,” Wachter says. “In the Serengeti in Tanzania, there is a lot of prey. They could come closer to each other, but they don’t.”Arjun Gopalaswamy, an independent wildlife biologist based in Bangalore, India, who has studied cheetahs in Kenya, agrees with Wachter’s assessment. “What’s so extravagantly special about Kuno that it can host that many cheetahs?” he asks.But Rajesh Gopal, chair of the Project Cheetah steering committee, says Kuno can “definitely” hold 21 cheetahs. “I don’t agree with [the critics] on that,” he says. But in describing Kuno, he includes 3,200 square kilometres of potential cheetah habitat adjacent to Kuno and 3,600 square kilomtres of nearby forested area as available range.Tordiffe points out a lack of data on cheetahs in India. “Trying to decide how many cheetahs Kuno National Park can accommodate cannot be determined by any expert,” he says. “They are basing these estimates on other systems — ones that do not exist in India at the moment.”Meanwhile, Weise questions whether enough cheetahs would survive and breed to sustain a viable population. “If you want a proper population, you need dozens, if not hundreds, of survivors. That’s a big challenge,” he says.Roaming cheetahsIndependent cheetah scientists also question Kuno’s proximity to farming communities. Translocated cheetahs in southern Africa explore thousands of square kilometres in the first 6 to 12 months after release, Weise says. “Imagine I tranquilize you, and I release you in Antarctica, and you wake up in a place that you’re not familiar with,” he says. “Any intelligent mammal will start looking around. We had records of individual animals moving between 40 and 70 kilometres in a night.”Weise and others expect that cheetahs will leave Kuno and enter the surrounding countryside. Two Kuno cheetahs have already roamed outside the park. “Almost by design, they are going to live in the farmlands,” Gopalaswamy says. “Now, there’s nothing wrong with that, but was that factored in? If they’re going to just disperse out and live with people, it’s a completely different question.”The action plan originally suggested that the animals would be restricted to the park, but Gopal says the project is preparing for roaming animals. He says that, in the next few weeks, government scientists will use remote sensing to study the 6,800 square kilometres of the park and its surrounds to find potential sites of cheetah–human conflict. “The forest department needs to create a community stewardship programme so villagers are rewarded financially for protecting the cheetah,” Gopal says. “This is not new for India,” he adds. “We have been handling tigers for the last 50 years.”Once the landscape-level threat analysis is complete, seven more cheetahs could be released by the end of this month, Gopal says.SuccessIn the long run, the success of Kuno’s cheetahs will depend on how tolerant people in the area are, Wachter says. “When the tiger and leopards are already there, whether they say, ‘OK, it doesn’t matter if we have the cheetah.’ Or whether they say, ‘This is now one carnivore too much, and we don’t want it.’”“I’m not entirely against moving them to India,” Weise says. “But if they have surplus animals and don’t know where else to put them, I’m not sure India is the best place.”Rather than introducing African cheetahs, India could focus instead on helping Iran to conserve its animals, Weise says. More

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RESEARCH HIGHLIGHT
06 June 2023

After gulls switched their focus from southern right whale mothers to calves, scientists recorded a drop in calf survival. More

The Tara during its 100,000-kilometre voyage around the Pacific Ocean.Credit: François Aurat/Tara Ocean Foundation

Scientists have known for decades that the biodiversity we know is a fraction of the biodiversity that exists. Even when it comes to perhaps the simplest measure, the number of species, researchers estimate that there could be anywhere between 3 million and 100 million species, of which some 1.7 million have been described. Every year, the names of some 10,000 new ones get added to the list.Gathering good biodiversity data can be a mission in itself, especially on marine biodiversity. One dependable source is a schooner called Tara, which celebrates 20 years at sea as a research ship this year. Tara has been to the Arctic Ocean and the Mediterranean Sea. Last week, researchers reported the results of its latest voyage, Tara Pacific, a two-year expedition across the Pacific Ocean, published in a collection of articles in Springer Nature journals (go.nature.com/45puzhk).
Epic voyage finds astonishing microbial diversity among coral reefs
Coral reefs are among Earth’s most diverse ecosystems, supporting 25% of marine life and providing services such as food, jobs and coastal protection to nearly one billion people worldwide. One region of the Pacific, the Coral Triangle — which includes the waters of Indonesia, Malaysia and the Philippines — has around 75% of the world’s coral species. But these nurseries for marine life are under threat: globally, around 50% of living corals have been lost since the 1950s (T. D. Eddy et al. One Earth 4, 1278–1285; 2021). Moreover, climate change poses a large risk to their continued survival.One of Tara Pacific’s research groups has been focusing on genetic diversity — in particular, that of microbial communities (bacteria and archaea) living in Pacific Ocean corals. The scientists, led by marine microbiologist Pierre Galand at the Banyuls Oceanological Observatory in Banyuls-sur-Mer, France, collected more than 5,000 samples, and focused on analysing the 16S ribosomal DNA marker gene, which is used to identify and classify microorganisms. They found around half a million distinct DNA sequences known as amplicon sequence variants (ASVs), which can be used as a measure of the genetic diversity in a sample (Nature https://doi.org/kddz; 2023). From these data, the researchers estimated that the microbial diversity of coral reefs globally is probably around 2.8 million ASVs (P. E. Galand et al. Nature Commun. 14, 3039; 2023). For comparison, this is close to the lower end of one genetic-diversity estimate of all of Earth’s bacterial and archaeal communities — a proposed range of 2.72 million and 5.44 million ASVs (S. Louca et al. PLoS Biol. 17, e3000106; 2019). Galand and his colleagues’ work, which builds on smaller-scale studies of coral reefs (M. Chiarello et al. Proc. R. Soc. B 287, 20200642; 2020), confirms that Earth’s microbial genetic diversity is much higher and richer than previously thought.
Collection: Tara Pacific
The research ship has a stirring and unusual back story. Its original captain was Peter Blake, a much-decorated professional yachtsman from New Zealand. After retirement, Blake became an environmental envoy to the United Nations but was killed by pirates at the mouth of the Amazon River while on an expedition in 2001. Agnès Troublé, a French fashion designer known as Agnès B, and her son Etienne Bourgois acquired the boat, determined to continue Blake’s original vision. They established the Tara Ocean Foundation and invited scientists and research funders to join them on various missions.The logistics of converting a schooner into a floating laboratory and taking it on a 100,000-kilometre journey cannot be underestimated, especially considering the present complicated relations between Pacific nations. And then there’s the logistics of the research itself: organizing 3,000 dives; sending samples for PCR analysis en route; keeping the voyage on track.Researchers must continue to build on the work being reported and refine our understanding of the importance of diversity for safeguarding ecosystem stability and function. The project is a great example of visionary thinkers such as Troublé and Bourgois working closely with funders and scientists to help us to understand the breathtaking diversity of the world around us before it is too late. When it comes to preserving the natural systems we all depend on, more such collaborations are needed. More

An air-quality monitoring station in London is located near a deer park, so it picks up DNA from species such as Dama dama (fallow deer) in its filters.Credit: Robert Knell

Scientists might be able to keep tabs on the world’s flora and fauna by analysing DNA floating through the air. That’s the conclusion of a study published on 5 June in Current Biology1, in which a team identified more than 180 types of organism, including plants, fungi, insects and animals, using DNA captured by filters from air-pollution monitoring stations. The researchers say that, because of the ubiquity of such stations, the method could transform the monitoring of biodiversity on Earth, and might even be able to detect rare species.Global biodiversity is plummeting — some estimates suggest a 69% drop in wildlife populations since 1970. Scientists struggle to keep track of changes in ecosystems and rates of species decline because they lack infrastructure to measure biodiversity on large scales. Typically, researchers or conservation volunteers monitor a few terrestrial species in small regions using labour-intensive methods such as camera surveillance, in-person observations and examining traces including footprints and faeces. Over large scales, only very general measurements are possible, such as assessments of forest cover.

Source: Ref. 1

But environmental DNA (eDNA) — small amounts of genetic material shed by living things — that is collected automatically using air-pollution tracking networks could help solve this problem, says Elizabeth Clare, a molecular ecologist at York University in Toronto, Canada, and lead author of the study.Scientists have been collecting and sequencing eDNA from soil and water samples for about 20 years to track rare or endangered species, such as the great crested newt (Triturus cristatus) in the United Kingdom and Gouldian finches (Erythrura gouldiae) in Australia. Regulatory agencies have used eDNA to detect invasive species; for example, the US Fish and Wildlife Service uses it to monitor silver carp (Hypophthalmichthys molitrix) in the Great Lakes system. But it wasn’t until last year that scientists, including Clare, reported that eDNA can be captured from air samples and used to explore terrestrial biodiversity2. The DNA probably comes from cells shed by organisms, researchers say.Biodiversity-monitoring stations?In the latest research, Clare and her colleagues ran a pilot study in which they got access to existing UK air-quality monitoring stations in London and near Edinburgh, to see whether they could trap airborne eDNA from the local flora and fauna. Both are designed to monitor atmospheric pollutants such as lead in particulate matter that becomes trapped in the devices’ filters. The Edinburgh station is part of a UK-wide network that is run in part by the National Physical Laboratory (NPL) in Teddington.

The US Fish and Wildlife Service uses eDNA to monitor silver carp (Hypophthalmichthys molitrix), an invasive species.Credit: Jason Lindsey/Alamy

The researchers set up the London station, which is next to a deer park, to take samples over various time intervals, from one hour to one week, allowing them to test whether sampling time is important. They also explored how long samples could be preserved by analysing the Edinburgh stations’ filters, which had collected DNA for a week before being stored for eight months.The research team, which included scientists from the NPL, extracted and sequenced eDNA from one-quarter of each filter. The scientists then compared the sequences with those available in DNA databases such as GenBank, run by the US National Institutes of Health.The researchers were surprised to find DNA from so many groups of organism on the filters. These included 34 species of bird, such as wrens (Troglodytes troglodytes) and great tits (Parus major), as well as ash trees (of the genus Fraximus), nettles (of the genus Soleirolia) and pathogenic Septoriella fungi (see ‘Keeping tabs on taxa’).Working out the detailsThe advantage of using existing air-monitoring stations is that this infrastructure is already set up in many countries around the world, including across North and Central America, Europe, Asia and the Southern Hemisphere, the researchers say. They urge monitoring-station operators to preserve filters after air-quality analysis so ecologists can use them.“Until we truly understand their ecological value, we’ve got to stop throwing them away,” Clare says.

Researchers retrieved wildlife DNA from the Auchencorth Moss air-quality monitoring station near Edinburgh.Credit: National Physical Laboratory/Local Site Operator

Eily Allan, a molecular biologist and chief scientist of the eDNA Collaborative, a research programme at the University of Washington in Seattle, says the automated collection of airborne eDNA using existing networks of air-monitoring stations could “push environmental monitoring into the twenty-first century”. It moves the research community from disjointed sampling to regular, repeated, long-term data collection, she adds.But before the monitoring method can be rolled out widely, researchers need to work out some details, including the optimal sampling time to ensure broad eDNA collection. The team says its data suggest that a day is too short for sampling, but a week is too long — there is a sweet spot between collecting enough DNA and keeping it for so long that the material degrades.Other unknowns include how far eDNA travels in air, which will determine how large an area this method can monitor. Study co-author Joanne Littlefair, a molecular ecologist at Queen Mary University of London, says the team is also still working out what ecological information eDNA can provide beyond identifying species. For example, she suggests it is unlikely that the method will be able to measure species abundance. But it could monitor bird migrations and how they are changing in response to climate change.“We don’t know really what you can reliably look at yet,” she says. More

Farming today is unsustainable, with its greenhouse-gas emissions and its destruction of wildlife habitats. Agriculture now takes up half of Earth’s hospitable land surface, at the expense of these habitats.Developing sustainable food production will require multiple approaches. My PhD research at Wageningen University in the Netherlands is inspired by alternative, indoor methods of food production, such as farming leafy green vegetables vertically and growing meat in a laboratory. I wondered — if you can grow meat without an animal, can you grow fruit without a plant?This could be done inside, which might help us to return some agricultural land to nature.During my master’s programme in agricultural engineering, I discussed indoor fruit production with my professor. He invited me to write a master’s thesis on the subject of growing fruits without the plant. Now, we’re testing this idea.The main task of my PhD is to collect immature fruit or flowers from tomato plants, and try to grow the stems into healthy, high-quality tomatoes in the lab. Ultimately, we want to produce fruit from tomato meristem cells — undifferentiated cells from which new plant organs can grow — and skip using a plant entirely.The jars in this photo contain some of the early results of my research, when I was testing different growing conditions at different stages of tomato development. The lighting is an energy-efficiency measure; we use blue and red LEDs, the best colours for photosynthesis.Some people get excited about the possibilities of my work, but most are hesitant, which I understand. In the past, people have rushed into using food technologies, such as cage-grown chickens and the extensive use of synthetic fertilizer, without considering the potential downsides. An important part of my PhD programme will be to assess the sustainability of my method. More