Ecology

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I am an ecologist from Zimbabwe, but I’ve been based at the National University of Lesotho in Maseru for more than 13 years. In the picture, I am standing in a stream that runs through the Bokong Nature Reserve, part of Lesotho’s first UNESCO biosphere reserve, designated in 2021.Lesotho is a mountainous, landlocked kingdom in southern Africa. Its high-altitude wetlands supply the Lesotho Highlands Water Project, which delivers water to the Vaal River System in South Africa, generating both income and hydroelectric power for Lesotho. The electricity lines in the background of this photo are part of that.I study the delicate ecological balance that keeps these areas functioning properly: the wetlands trap water when it rains and release it gradually during dry periods. An important part of this is to map the vegetation, animals and general environmental conditions, and how they change over time.One of our projects monitors the soundscapes of these areas to identify the animals that live here. We leave our sensitive recording equipment in the field for weeks at a time. This is especially helpful because, although this site is just 180 kilometres from my university in the capital of Lesotho, it can take up to four hours to drive here.The data sets we gather are huge, and although we do listen to the recordings, we mainly use software to help us analyse the data. We want to compare our recordings between seasons, between dawn and dusk and between day and night, to understand the rhythms of the ecosystem. We also compare our recordings from different wetland types. High-altitude areas are susceptible to climate change and, in my view, it is the greatest threat these protected wetlands face.Listening to the recordings makes me happy because I enjoy hearing a variety of sounds, especially the singing of different birds. In a small country such as Lesotho, there are so many knowledge gaps to fill — it’s one of the benefits of being a researcher here. More

An advocate for endangered species both inside and outside the courtroom, Kumar Paudel tracks pangolins in central Nepal.Credit: Greenhood Nepal

As a child born and raised in Sindhupalchowk, a remote, hilly district northeast of Kathmandu, Kumar Paudel had heard plenty of stories about wildlife smuggling. The region is home to a major trade route exploited by smugglers trafficking wildlife from Nepal to China. He had seen people rapidly amass wealth through illegal trade of red sandalwood (Pterocarpus santalinus), pangolins and red pandas (Ailurus fulgens).In 2010, while pursuing a bachelor’s degree in environmental science at Amrit Campus in Kathmandu, Paudel often encountered news about wildlife poaching, especially that of the endangered greater one-horned rhinoceros (Rhinoceros unicornis). He and his friends organized political protests and rallies, which resulted in improved parliamentary investigations into controlling wildlife poaching. Encouraged by their success, he co-founded Greenhood Nepal, a non-profit conservation organization based in Kathmandu that is dedicated to saving the country’s endangered flora and fauna. Paudel spoke to Nature about his study of the illegal wildlife trade, and how interviewing people who had been incarcerated for wildlife crimes inspired him to take his cause to Nepal’s highest court.What led you to visit prisons as part of your conservation research?When I started my master’s programme at the School of Environmental Science and Management in Kathmandu in 2012, I was already advocating for wildlife through public forums, writing newspaper opinion pieces and organizing outreach events. For my thesis, I connected all of these experiences to the smuggling cases in my home town, to explore the illegal trade route.But reaching out directly to traders involved in an illegal business was challenging. I opted to visit prisons and talk with people serving sentences for wildlife poaching. I had a lot of questions: who were these people? Where do they come from? I later realized that most of them hailed from remote, marginalized communities, were from low-income families and lacked basic education. Many of them underestimated the social cost that their imprisonment would have on their families.How did your master’s research evolve into advocacy?While attending a wildlife-crime conference in South Africa in 2015, I met Jacob Phelps, a wildlife-trade researcher at Lancaster University, UK. Phelps was impressed that I was visiting prisons, and he advised me to expand the research into a nationwide study. I sampled seven prisons in the country and carried out in-depth interviews with 116 incarcerated people.Visiting prisons and listening to the life stories of the people there helped me to connect with them and understand their struggles. In August 2016, I saw a preview of a television interview in which a former prime minister of Nepal displayed a large tiger pelt at his residence. The disparity struck me — the poorer people in prison had been convicted for their roles in the illegal wildlife trade, but the powerful could showcase parts of endangered animals on national television with no consequences.What did you do about it?I went to social media to ask for answers from enforcement agencies. I learnt that Nepal’s law clearly states that possession of wildlife parts without a registered licence is as illegal as trading protected animals. The law required any person possessing any protected wildlife parts to register them with the Department of National Parks and Wildlife Conservation. Surprisingly, when I checked in 2016, not a single person had done so.

Paudel teaches an Indigenous community in Chitwan, Nepal, about pangolin conservation.Credit: Greenhood Nepal

I repeatedly followed up with the Ministry of Forest and Environment, the Nepal Police and the Central Investigation Bureau. An officer at the environment ministry threatened me, saying that he could get me arrested if I kept pursuing the issue. I have to be honest: as a young researcher, I was scared. But after two years of getting no concrete answers, I sought legal action.How did you prepare for a court battle?Because I had been following up for nearly two years, I had a lot of evidence. I found an environmental lawyer — Padam Bahadur Shrestha, based in Kathmandu — who helped me to refine the petition and file it with the Nepal Supreme Court.I knew that getting results out of the court system would be a frustrating process. I had heard about people who had waited decades for a decision. But I had no other options. My case garnered significant attention from lawyers and the public, because one of the judges who was supposed to hear it owned several wildlife parts.My case went through 14 deferrals over five years. Last May, the Supreme Court finally heard my case. In my petition, I claimed that the government did not keep track of individuals who owned wildlife parts, and that the government was enforcing laws inequitably. The court acknowledged that my claim was valid and requested written answers from the government.What arguments came up in the case?The court extensively discussed one crucial matter: how law-enforcement bodies can intervene in matters related to people’s cultural beliefs. In Nepal, there is rich cultural diversity, and wildlife parts can hold cultural, religious and ancestral values. I defended my stance by emphasizing that, despite the parts’ symbolic meaning, wildlife is an important aspect of our biodiversity. Bringing the wildlife parts under a legal framework should help to deter illegal smuggling without hurting their historical and cultural significance.What was the government’s response? Did the ruling change how wildlife laws are enforced?The government acknowledged the failure to keep records of wildlife-part ownership. The court directed the government to take a proper accounting of who possessed such parts, including evidence for those in legal possession. It ordered the confiscation of illegally owned parts.Although the issue has been politicized because it involved powerful people, the ruling set a precedent for the regulation of wildlife-trade crimes. The decision also supports enforcement officers, enabling them to pursue powerful figures if needed. The court order brings thousands of illegal wildlife parts under enforcement, regardless of who owns them.What’s next for you?I plan to continue working in conservation science and social justice, whether through courtroom battles or documentation of threatened species. Although conservation science is my main focus, I recognize the importance of translating theoretical discussions into the laws and policies that dictate how society operates. I hope that my case sets an example that there are times when researchers can transcend academic boundaries. More

Download the Nature Podcast 07 February 2024 In this episode:0:46 Borrowing tricks from cancer could help improve immunotherapyT-cell based immunotherapies have revolutionized the treatment of certain types of cancer. However these therapies — which involve taking someone’s own T cells and reprogramming them to kill cancer cells — have struggled to treat solid tumours, which put up multiple defences. To overcome these, a team has taken mutations found in cancer cells that help them thrive and put them into therapeutic T cells. Their results show these powered-up cells are more efficient at targeting solid tumours, but don’t turn cancerous themselves.Research article: Garcia et al.11:39 Research HighlightsHow researchers solved a submerged-sprinkler problem named after Richard Feynman, and what climate change is doing to high-altitude environmental records in Switzerland.Research Highlight: The mystery of Feynman’s sprinkler is solved at lastResearch Highlight: A glacier’s ‘memory’ is fading because of climate change14:28 What might the car batteries of the future look like?As electric cars become ever more popular around the world, manufacturers are looking to improve the batteries that power them. Although conventional lithium-ion batteries have dominated the electric vehicle market for decades, researchers are developing alternatives that have better performance and safety — we run through some of these options and discuss their pros and cons.News Feature: The new car batteries that could power the electric vehicle revolution25:32 Briefing ChatHow a baby’s-eye view of the world helps an AI learn language, and how the recovery of sea otter populations in California slowed rates of coastal erosion.Nature News: This AI learnt language by seeing the world through a baby’s eyesNature News: How do otters protect salt marshes from erosion? ShellfishlySubscribe to Nature Briefing, an unmissable daily round-up of science news, opinion and analysis free in your inbox every weekday.Never miss an episode. Subscribe to the Nature Podcast on Apple Podcasts, Google Podcasts, Spotify or your favourite podcast app. An RSS feed for the Nature Podcast is available too. More

Tree-planting initiatives, including the World Economic Forum’s 1 Trillion Trees project (www.1t.org) launched in 2020, are a popular way to tackle climate change and biodiversity loss. But challenges such as quantifying carbon stored, the time it takes trees to grow and competing land uses mean that these projects are increasingly supplemented with a swifter solution: pollinator protection.
Competing Interests
The author declares no competing interests. More

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Sea otters in California prey on crabs, thereby inadvertently protecting the vegetation that holds creek banks together.Credit: David Hayes/Alamy

Sea otters are helping to keep the shores of a central Californian estuary from crumbling into the ocean. They act as erosion control by feasting on shore crabs — crustaceans whose burrowing and vegetation-munching habits contribute to unstable salt-marsh banks.By the twentieth century, humans had hunted sea otters (Enhydra lutris) nearly to extinction for their fur. But conservation efforts have helped population sizes to increase, and otters are re-establishing themselves in their historical haunts, including in the salt marshes of Monterey Bay’s Elkhorn Slough. Moreover, in marsh creeks with high numbers of sea otters, erosion rates are lower than when there were fewer sea otters, researchers report today in Nature1.“It’s remarkable when you think about it,” says Jane Watson, a community ecologist at Vancouver Island University in Nanaimo, Canada. “You can have a single animal, the sea otter, come in and through predation actually mitigate the effects of erosion.”Natural vegetation protectorsSalt marshes provide crucial habitats for wildlife but are threatened globally. Several factors, such as increased water flow and sea-level rise, contribute to the amount of erosion in Elkhorn Slough — estimated at around 30 centimetres per year. Striped shore crabs (Pachygrapsus crassipes) also play a part by eating the roots of pickleweed (Salicornia pacifica), an abundant plant that helps to hold the slough’s sandy banks together. Because sea otters eat the crabs, study co-author Brent Hughes, a marine ecologist at Sonoma State University in Rohnert Park, California and colleagues wanted to know whether the predator’s recovery would change the levels of erosion in the area.To dig into the correlation between erosion and sea otters, the team compared several lines of evidence, such as historical erosion rates in Elkhorn Slough and sea otter population trends. They also did a predator-exclusion experiment, in which otters could eat burrowing crabs in some creeks but not in others. Then, the team compared how much vegetation grew in each of those areas.Turning the tide on erosionOn banks where sea otters could prey on crabs, the vegetation was denser than on those from which they were excluded. Hughes says that sea otters have had a similarly positive impact on other vegetation elsewhere, such as seagrass and giant kelp. “It’s almost like, wherever they go, they’re protecting vegetation,” he says. In areas where otters had returned, erosion slowed from 30 cm a year to 10 cm a year.As their populations increase and they reclaim their historical range, sea otters could turn the tide of erosion in other salt marsh habitats — particularly the marshes of the nearby San Francisco Bay, Watson says. More

Elephants in India often roam outside official forest reserves.Credit: David Talukdar/Getty

India’s Supreme Court has agreed this week to hear arguments in a challenge to a controversial new forest law. An official request for a hearing was filed to the Supreme Court last Octoberber by 13 former officials in the forest service and environment ministry, who say the amended Forest Conservation Act is unconstitutional. The next hearing, which is yet to be scheduled, is the latest in a series of protests against the law — which some scientists say makes it easier to clear forests for development and erodes the rights of millions of people who depend on these ecosystems.M. K. Ranjitsinh Jhala, a former departmental head at the Ministry of Environment and Forests, and a co-petitioner in the case, says the revised act would harm the ecology of India and the livelihoods of forest-dwelling people. “There’s nothing in that act that we can see is going to help nature conservation, food security, ecological security and livelihood,” he says.The Forest Conservation Act was originally created in 1980, to balance the demands on forests from wildlife, local communities, businesses and the government. It protected all forested land from being used for agriculture, timber plantations, logging or other commercial purposes. If land-holders wanted to develop the land, they had to submit plans to the central government for approval, and “compensatory afforestation” was often required.The Indian Parliament voted to amend the act last August, opening up large areas of forests for development and exempting some new projects from requiring approval. The act was to come into force in December, but is paused pending the outcome of the hearing.The passage of the bill through parliament took place against a backdrop of protest from scientists, environmental groups and tribal people. India is described by ecologists as megadiverse, containing about 8% of all recorded species. Forests covered 21% of the country in 2021, according to the India State of the Forest 2021 report. And only 5.3% of it is strictly protected. Some wide-ranging mammals, such as the tiger (Panthera tigris) and the Asian elephant (Elephas maximus), live beyond these protected areas, in adjoining lands. The new act could fragment their habitats, leading to increased human–wildlife conflict, says Sandeep Sharma, an ecologist at the German Centre for Integrative Biodiversity Research in Leipzig, who is not a signatory to the petition. Fragmentation would also reduce the ecosystem’s ability to provide services to humans, such as fresh water or clean air, he says. “The water from a contiguous patch of forest is different than the water you get from a fragmented forest,” he says.Nature contacted India’s Ministry of Environment, Forest and Climate Change for comment, but it did not respond by the time of publication.The actOne key change to the act hinges on the legally accepted meaning of ‘forest’. A Supreme Court ruling on the act in 1996 defined the word according to the dictionary, which per the Oxford English Dictionary is “a large area covered chiefly with trees and undergrowth”. Now, the government recognizes only areas registered in official records as forests.Ecologists estimate that 27.6% of India’s forest cover, an area that is roughly the size of Uganda, is unrecorded and would lose protection. The environment ministry has asked states to map and record their forests within one year, but this will prove challenging, says Meenal Tatpati, an independent lawyer and environment researcher based in Pune, India. She says the Supreme Court mandated in 1996 that states set up expert committees to identify unrecorded forests, but 27 years later, most still have not done so.The amended act also grants exemptions from review for national-security or defence reasons. But Ranjitsinh says the law is imprecisely worded, which would allow interpretations that “are not quite according to the spirit of the law, and sometimes not even according to the letter of the law”.Projects within 100 kilometres of India’s borders that are of “national importance” or that serve “national security” purposes are exempt from review under the act. This covers a vast region hosting numerous wildlife sanctuaries and forests, Sharma says. The borderlands include rare forests in the Andaman and Nicobar islands and are home to species of global significance, including vulnerable snow leopards (Panthera uncia) in the Changthang Wildlife Sanctuary in the Himalayan desert and the critically endangered great Indian bustards (Ardeotis nigriceps) in Rajasthan.It also exempts parcels of land alongside roads and railway lines from development approval. Although the exempt parcels are small, they could add up to a large area: India has more than 144,000 kilometres of highways and 123,000 kilometres of tracks.

Snow leopards (Panthera uncia) inhabit areas within 100 kilometres of India’s borders.Credit: Shivang Mehta/Getty

The amendment has made the steps for obtaining consent from tribal peoples less prescribed. Soumitra Ghosh, a forest-rights activist at the All India Forum of Forest Movements, based in Siliguri, says more flexibility in the approvals process might allow some developers to cut corners in consulting with forest-dwellers. Some 300 million people live in villages bordering forests and directly depend on them, according to the India State of the Forest 2019 report. These include tribal people, some of whom have lived in and around the forests for millennia.International commitmentsThe changes to the act could also imperil India’s international commitments, says Tatpati. Under the 2022 Kunming–Montreal Global Biodiversity Framework, India has promised to conserve 30% of its land and oceans. It says that 27% is already under some kind of protection.To reach the 30% target, the Indian government plans to encourage local governments, communities and private landowners to declare areas such as village commons, community forests, artificial water bodies and canals as protected under the classification of other effective area-based conservation measures (OECMs).But Sharma says that community and privately owned forests classified as OECMs would not be protected under the amended act. The owners could choose to declassify these areas at any point, making India’s biodiversity target hostage to the whims of landowners.Sharma says that India is nonetheless likely to meet its 30% target, because the biodiversity framework does not specify the quality of conserved areas, only the quantity. A plantation forest created to replace an ancient stand would count, he says.The court has not yet determined when it will hear arguments from the petitioners and the government. Ranjitsinh hopes the Supreme Court will strike down the entire amended act, reverting to the original. “It depends upon the court,” he says. “We all hope and pray it should be successful.” More