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    The baseless stat that could be harming Indigenous conservation efforts

    Download this episode of the Nature PodcastThe often repeated claim that “80% of the world’s biodiversity is found in the territories of Indigenous Peoples” appears widely in policy documents and reports, yet appears to have sprung out of nowhere. According to a group of researchers, including those from Indigenous groups, this baseless statistic could be undermining the conservation efforts of the Indigenous People it’s meant to support and prevent further work to really understand how best to conserve biodiversity.Two of the authors joined us to discuss how this statistic gained traction, the harm it could cause, and how better to support the work of Indigenous Peoples.Read more in a Comment article from the authors: No basis for claim that 80% of biodiversity is found in Indigenous territoriesSubscribe 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, Spotify, YouTube Music or your favourite podcast app. An RSS feed for the Nature Podcast is available too. More

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    No basis for claim that 80% of biodiversity is found in Indigenous territories

    Tsimane’ people in the Bolivian Amazon weave palm leaves together to thatch dwellings.Credit: Joan de la Malla

    For the past 20 years or so, a claim has been made in all sorts of outlets, from reports and scientific publications to news articles, that 80% of the world’s biodiversity is found in the territories of Indigenous Peoples. Those using this figure invariably aim to highlight the essential roles that Indigenous Peoples have in conserving biodiversity, and seem to have quoted it in the belief that it is based on solid science.Numerous studies demonstrate that Indigenous Peoples and their territories are indeed key to safeguarding biodiversity for future generations1,2. But the claim that 80% of the world’s biodiversity is found in Indigenous Peoples’ territories is wrong.
    Indigenous knowledge is key to sustainable food systems
    The continued use of this number by United Nations agencies, non-governmental organizations (NGOs), journalists, conservation biologists and Indigenous activists and advocates, among others, could damage the exact cause that it is being used to support. Efforts to draw on and prioritize Indigenous Peoples’ knowledge in biodiversity conservation, and to protect their governance and rights, could be undermined if the credibility of individuals and organizations who make this claim is questioned.The global conservation community must abandon the 80% claim and instead comprehensively acknowledge the crucial roles of Indigenous Peoples in stewarding their lands and seas — and must do so on the basis of already available evidence.Fact or fiction?The 80% claim is based on two assumptions: that biodiversity can be divided into countable units, and that these can be mapped spatially at the global level. Neither feat is possible, despite important advances in measuring biodiversity3. In fact, according to the Convention on Biological Diversity — a multilateral treaty to develop strategies for the conservation and sustainable use of biological diversity, involving nearly 200 countries — biodiversity is the “diversity within species, between species and of ecosystems”4. It is not something that can be easily quantified.Even if researchers resorted to using the number of species present as a measure of biodiversity — a narrow yet common proxy — there are still millions of species that have not been described. Furthermore, there is debate over the proportion of described taxa that represents valid species, and knowledge about the geographical distributions of most species is lacking or incomplete. Data on species counts and distributions are especially likely to be missing for Indigenous Peoples’ lands and seas.

    A traditional rice terrace built by members of the Torajan people in Sulawesi, Indonesia.Credit: Joan de la Malla

    The 80% claim seems to stem from misinterpretations of previously published statements. As advocates for Indigenous Peoples (three of us identify as Indigenous), we have had discussions about this figure over several years with Indigenous leaders at policy forums, on field visits and in research projects. To track its origins and assess how frequently it has been cited in the literature and in what contexts, we searched for combinations of the words ‘Indigenous’, ‘80%’ and ‘biodiversity’, as well as for combinations of their variants, such as ‘eighty’, ‘percent’ and ‘biological diversity’. We conducted our search using Google Scholar and Clarivate’s Web of Science, and included literature published up to 1 August this year.Our search found no reference to the 80% assertion before 2002. A report that year by the UN Commission on Sustainable Development, a body tasked with assessing progress on the commitments agreed at the 1992 UN Conference on Environment and Development in Rio de Janeiro, Brazil, stated that Indigenous Peoples “nurture 80% of the world’s biodiversity on ancestral lands and territories”5. Over the next six years, similar unattributed statements were made in four other reports (see Supplementary information). However, judging by how commonly the number is cited, it seems to have been a 2008 World Bank report6 that contributed most to its widespread adoption in the academic literature (see ‘Poor fact-checking’).

    Source: Analysis by Á. Fernández-Llamazares et al.

    On the basis of the citations we tracked in our literature review, the earliest potential source for the 80% claim that we could identify is a chapter in the 2001 edition of the Encyclopedia of Biodiversity7. Three documents cite this publication, including a 2009 report by the Food and Agricultural Organization of the UN (FAO)8. It states: “Approximately 80 percent of the world’s remaining biodiversity is found in indigenous peoples’ territories.” But the encyclopedia actually asserts that “nearly 80% of the terrestrial ecoregions are inhabited by one or more indigenous peoples”7. In other words, the original statement, along with the analysis underpinning it, merely quantified the proportion of the world’s 136 terrestrial ecoregions in which Indigenous Peoples were living.The influential World Bank report6 does not cite the encyclopedia, but instead gives the source as a 2005 publication by the World Resources Institute (WRI), a global non-profit research organization in Washington DC. However, the closest the WRI publication comes to supporting the statement is the observation that seven Indigenous communities in the Philippines were “maintaining over 80 percent of the original high-biodiversity forest cover”9.Out of nowhereAmong the 348 documents that we found to include the 80% claim are 186 peer-reviewed journal articles, including some in BioScience, The Lancet Planetary Health and Philosophical Transactions of the Royal Society, and 19 news articles targeted at a specialist audience, including one in Nature (see Nature https://doi.org/ndqf (2024) and Supplementary information). The claim has been repeated by the Convention on Biological Diversity10 and by NGOs such as the conservation group WWF. One study in the Proceedings of the National Academy of Sciences even states that Indigenous Peoples “protect approximately 85% of the world’s biodiversity through stewardship”11.

    Maasai women in Kenya lead a community-based rangeland restoration project.Credit: Joan de la Malla

    The 80% figure has also gained attention in the wider media and has entered popular culture. For instance, the film-maker James Cameron used it in 2022 when publicizing his film franchise Avatar. It has become so engrained in public discourse that even the online fact-checking service GigaFact confirms it to be true (see go.nature.com/4cwxgcd).
    Weaving Indigenous knowledge into the scientific method
    In our literature review, we found only two documents that questioned the claim: a blog post (see go.nature.com/4dqbavs) and a footnote in a policy brief by the ICCA Consortium, an organization that promotes recognition of the territories of Indigenous Peoples and local communities12. Some Indigenous Peoples’ representatives acknowledge that they have been unable to find supporting evidence for the claim. And some Indigenous leaders have told us that they avoid endorsing the figure.Our criticism of the 80% claim should in no way undermine decades of effort by Indigenous Peoples’ organizations and others to influence international biodiversity and climate policy. Nor should it detract from the essential and verifiably considerable part that Indigenous Peoples play in the conservation of the planet’s biodiversity. For example, a 2018 analysis13 led by one of us (S.T.G.) indicated that, at the time, Indigenous Peoples managed or held tenure rights over more than one-quarter of Earth’s terrestrial surface — land that intersected with at least 37% of the remaining natural lands worldwide (see ‘Fact, not fiction’).

    Source: Ref. 13

    Subsequent studies have shown that Indigenous Peoples’ lands include more than one-third of the world’s intact forest landscapes (forest ecosystems that show little sign of habitat conversion or fragmentation)1,2,14,15. And around 60% of all terrestrial mammals for which reliable habitat data exist (comprising more than 2,500 species) have more than 10% of their ranges in Indigenous Peoples’ lands16. Compared with protected areas, these lands support at least as many species (when matched for habitat type, location and so on), have fewer alien species and have retained a similar proportion of habitat2,14,15. Indeed, in the past five years, the essential roles of Indigenous Peoples in global biodiversity conservation have been recognized in numerous landmark reports3,17.On the contrary, our concern is that the 80% claim could undermine these and other rigorous studies — as well as effective efforts to conserve biodiversity by Indigenous Peoples on the ground. Putting aside the fundamental problems with this specific statistic, trying to assign a numerical value to biodiversity on Indigenous Peoples’ territories fails to represent Indigenous values and world views in a meaningful way.More than a numberThe integral connections between Indigenous Peoples and their lands, seas and resources help to conserve biodiversity worldwide in varied ways3,17. This is apparent from scholarship that draws on Indigenous Knowledge across cultures, from oral narratives passed down through generations, and from cultural practices to manage biodiversity17. Assessing the impact of Indigenous Peoples on the safeguarding of biodiversity requires taking into account the many complex interrelations between humans and non-human nature, not just the number of species and ecosystems in a region.

    Tsimane’ women in Bolivia make baskets using the leaves of a palm tree.Credit: Joan de la Malla

    The implicit assumption behind the 80% claim is that the characterization of biodiversity is complete. Indeed, the implied certainty suggests that Indigenous scholarship and Indigenous Knowledge systems might not be needed to improve understanding of the state of biodiversity on Indigenous Peoples’ lands and in their seas. Although Indigenous Knowledge holders and scholars have long understood the importance of Indigenous governance for the stewardship of biodiversity, an understanding of this is only just beginning to develop among the broader public.The global conservation community must abandon the unsupported 80% claim, and instead acknowledge more comprehensively the crucial roles of Indigenous Peoples in biodiversity conservation, restoration and stewardship. This means acting in partnership with and supporting the leadership of Indigenous Peoples, recognizing their rights to their lands and seas, and involving them as leaders or as equal partners in decision-making. It means amplifying Indigenous voices in international biodiversity and climate-change forums, and providing Indigenous Peoples with resources so that they can lead their own conservation initiatives.Genuinely valuing and integrating the ecological knowledge of Indigenous Peoples will lead to a more just and effective approach to conserving the planet’s biodiversity. More

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    To conserve biodiversity, create spaces where natural selection is allowed free rein

    Genetic diversity is essential to biodiversity. When environmental conditions change, as with global warming, genetic modifications under natural selection help to prevent populations and species, especially of sessile organisms such as plants, from extirpation. Governments and conservation authorities worldwide must do more to set aside areas where natural selection can occur without human intervention.
    Competing Interests
    The authors declare no competing interests. More

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    International whaling convention needs boosting, not dismantling

    Peter Bridgewater et al. call for the International Whaling Commission (IWC) to be dismantled because it has “so little to show” since the moratorium on commercial whaling began in 1985 (P. Bridgewater et al. Nature 632, 500–502; 2024). I have attended numerous IWC meetings as both a governmental delegate and an observer. The authors are wrong.
    Competing Interests
    The author declares no competing interests. More

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    Why repairing forests is not just about planting trees

    Treewilding: Our Past, Present and Future Relationship with Forests Jake Robinson Pelagic (2024)Trees first appeared around 400 million years ago. They survived the mass-extinction event that wiped out the dinosaurs some 66 million years ago and lived through several glacial periods during which ice covered up to one-quarter of Earth’s land. Now, they face another threat: humans.Since the birth of agriculture, people have been clearing forests to make space for crops and livestock. Over the past 300 years, 1.5 billion hectares of forest have been lost — equivalent to around 37% of today’s total forest cover. This has resulted in biodiversity loss, desertification and increased flooding risks. Deforestation has also been linked to an increased chance of disease outbreaks, because people come into contact more often with animals, such as bats, that carry potential pathogens and whose habitats have been destroyed.In Treewilding, microbial ecologist Jake Robinson explores how we can best protect existing forests from deforestation and restore those that have been lost, while acknowledging that some degree of deforestation is inevitable. His meticulous explanations and vivid descriptions make this book a must-read.
    Greener cities: a necessity or a luxury?
    Robinson questions whether just planting trees is the solution to deforestation. Although tree-planting initiatives have been going on since the Second World War, they have exploded since the turn of the century. The public has become increasingly aware that trees can help to prevent soil erosion and desiccation, and are crucial to mitigating climate change by sequestering carbon. Globally, the area of planted forests rose from 170 million hectares in 1990 to 293 million hectares in 2020. Tree-planting initiatives are used by many organizations to ‘greenwash’ their high carbon footprints — making them seem environmentally friendly when they are not. However, unless thoroughly researched and well implemented, tree planting can do more harm than good to ecosystems.Often, only one type of tree is planted across swathes of land. Such monocultures reduce biodiversity, in terms of plant species and the wildlife and microorganisms associated with them. Because trees of the same species are susceptible to the same diseases, a whole forest can be wiped out at once. Moreover, non-native trees can be invasive species, disrupting delicately balanced local ecosystems.Regenerate forests to restore themTo solve rather than compound environmental crises, Robinson argues, a more informed approach is needed. Regulators must understand the deep connections that trees and forests share with people, animals and microbes.He speaks to Forrest Fleischman, a scholar of forest and environmental policy, who underscores how Indigenous peoples depend on forests for subsistence farming and grazing animals. High-income countries contribute the most to climate change, yet tree-planting initiatives risk unfairly displacing Indigenous people in low-income countries, says Fleischman. He proposes that people should not just plant trees but ‘grow’ them. This means knowing what species suit an area and how they are connected to the lives of the local people and wildlife. Growers should make use of local knowledge and spend time and money caring for young trees.

    The Great Green Wall project aims to reforest a belt of land across the Sahara desert.Credit: TCD/Prod.DB/Alamy

    Robinson details a range of forest-restoration projects that fit this brief. The ‘Great Green Wall’ project, for instance, aims to grow a belt of trees nearly 8,000 kilometres long and 15 kilometres wide across the Sahara Desert, along a route that was forested 50 years ago. If successful, it could prevent the southward expansion of the desert by reducing land degradation; increasing the amount of arable land, the crop yield and the availability of jobs; and sequestering millions of tonnes of carbon. Several million trees have been planted since 2007. But funding has dried up, and the author cautions that more money must be found if the Great Green Wall is to succeed.Another admirable restoration project is Western Australia’s Gondwana Link, which aims to reduce vegetation loss by reconnecting small patches of previously linked forest across 1,000 kilometres. This should help species at risk of extinction in isolated patches to endure. It could increase the chance of survival for birds, such as the Australasian bittern (Botaurus poiciloptilus) and hooded plover (Charadrius cucullatus), and plants, including the Corackerup marlock (Eucalyptus vesiculosa). When populations that are currently separated can intermix, their genetic diversity is improved. This can help to protect them against environmental adversity. Since 2002, the project has planted 14,500 hectares of land, funded in part by investors who receive carbon credits or tax exemptions in return.The author also describes his own work in ecoacoustics. The approach uses the sounds made by organisms including birds and bats to explore the composition of and changes in ecosystems. Working with bioacoustics specialist Carlos Abrahams, Robinson is studying soil biodiversity to track forest restoration. As forests are rejuvenated, they’ve found, the number of invertebrates hidden in the soil increases, producing a “subterranean soundscape — a hidden orchestra of life”.
    Wood — the vein that runs through human history
    Robinson ultimately concludes that natural regeneration — leaving a damaged woodland to repair itself — is one of the best ways to restore forests. He compares this phenomenon to a phoenix: “Just as the mythical bird is reborn from its own ashes, a forest can regenerate from the remnants of its own destruction.”I was hooked by Robinson’s ability to paint rich pictures of beautiful scenery. Arriving at a restored forest on a limestone cliff in the Peak District, UK, for example, he sees “a vast sea of greater knapweed glancing down at me from the edge like floral guardians in a watchtower”. The soil underfoot is “a bed of compressed and mineralised marine creature skeletons from bygone eras”.And I enjoyed the thought-provoking questions raised throughout. For instance, to what extent can people alive today understand what the baseline state of the environment should be, given how rapidly human activity is changing the world? And how do jays (Garrulus glandarius) — voracious acorn eaters — understand that they need to set aside some nuts to help to regenerate the oaks they depend on for nutrition? The birds probably simply forget that they’ve hoarded caches of food, but Robinson speaks to several scientists who have found evidence that hoarding is an intelligent, rather than hard-wired, behaviour. This exploration exemplifies the author’s ability to avoid bias as he explores delicate subjects, despite his clear passion for them.Treewilding effortlessly integrates current theories with fresh insights and consolidates strands of research into a coherent narrative that should encourage researchers to come up with better ways to help forests. It is an enlightening journey for anyone interested in the science of nature. More

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    Tales of a migratory marine biologist

    Christine Gabriele spotting the tail fluke of a humpback whale in Hawaiian waters. Her career has followed the whales’ migration back and forth from their tropical breeding grounds in Hawaii in winter to summer feeding areas in Alaska.Credit: Susan Rickards, taken under NOAA Fisheries scientific research permit 26596

    Working scientist profiles

    This article is part of an occasional series in which Nature profiles scientists with unusual career histories or outside interests.

    Leaving Kawaihae harbour in Hawaii at 7.42 a.m. on a bright sunny morning in March, the volunteer crew of the Sealegs, an amphibious boat, passes some brown boobies (Sula leucogaster) on a buoy. “We call them Barbie Booby and Bobby Booby,” smiles Christine Gabriele, noting that after frequent sightings decades earlier, the seabirds had disappeared from here, returning only in 2021. “Something must’ve changed,” she says, noting that ocean life still holds so many mysteries. Unravelling some of them, by tracking long-term changes through careful monitoring of marine mammals, has been a focus of her work.Gabriele’s eyes are keenly focused on the azure waters ahead. “Sorry for not making eye contact. I’m always scanning, scanning, scanning,” she says, referring to the search for humpback whales (Megaptera novaeangliae). Spotting tails and fins is more challenging than usual this morning. Strong winds overnight have not entirely calmed. Windy spells are common along this northernmost peninsula of Hawaii’s Big island. Inside Gabriele’s house on the hillside a few kilometres above, every door has wall hooks to prevent slamming by sudden gusts. “Your hat might blow off today,” warns Gabriele’s colleague Suzanne Yin, as we motor away from shore.

    Marine biologist Christine Gabriele’s work has documented the whales’ lifespan, reproductive biology, vocalizations and response to a devastating marine heatwave, among other topics.Credit: Suzanne Yin

    Yin explains that when drawing attention to whales, “we try to use the vessel as a clock”. I’m instructed that if I see a whale, I’m not to point and shout “over there”, but rather to declare “Whale at 12 o’clock”, for example, to indicate one straight ahead.Just 20 minutes into the trip, a misty plume rises from a whale’s blowhole. “Whale up,” says Gabriele, snapping photographs of the underside of its fluke, as the creature’s two-lobed tail is called, with her telephoto lens.It is the first of many whale observations on this seven-hour monitoring trip. A few hours later, the volunteer crew lowers a hydrophone into the water to eavesdrop on humpbacks nearby. Against the background static of snapping shrimp come the haunting, rising and descending songs of several whales in concert. The calls sound like ghostly oooohs and creaky-door squeaks. Systematic recording of whale song is one way in which Gabriele’s team monitors local whale abundance. A few minutes later, a school of 50 or more spinner dolphins (Stenella longirostris) swims by, some pirouetting as they porpoise in and out of the water.The pull of the sea“I’ve always loved the ocean,” Gabriele says. Growing up in upstate New York, she developed a fascination for marine mammals early on, and her interest was fuelled by family seaside holidays. As an undergraduate at Cornell University in Ithaca, New York, she studied biology and animal behaviour. An undergraduate semester at sea on a schooner travelling from Massachusetts to the West Indies solidified her love for marine biology.

    A humpback whale calf breaches off Kawaihae harbour, Hawaii Island.Credit: Christine Gabriele, taken under NOAA Fisheries scientific research permit 26596

    After her undergraduate degree, Gabriele worked in an auditory biology lab in Boston, Massachusetts. “I loved the job. But it cemented for me that I wanted to work outdoors,” says Gabriele. So she applied for graduate courses and landed a place on a master’s programme at the University of Hawaii at Manoa in Honolulu, studying the reproductive behaviour and Hawaiian residence time of humpback whales.She graduated in 1992, and afterwards a colleague who had initiated a whale-monitoring programme in the Glacier Bay region of Alaska moved to New Zealand, creating a vacancy. Gabriele applied for and secured the job, which was with the National Park Service in Gustavus, Alaska. She has spent much of the past 34 years as a wildlife biologist studying the humpbacks that spend May to October feeding in the nearby Glacier Bay National Park. However, as someone determined to have a year-round understanding of their biology, she found a way for her career to mirror their migratory patterns.
    Flying low and slow over endangered whales
    During her graduate studies in Hawaii, Gabriele never saw a feeding humpback whale, she says. North Pacific humpbacks feed little, if at all, while in Hawaiian waters, which are their main winter breeding grounds. Each winter and spring, thousands of whales — about half of all humpbacks swimming in the North Pacific, not just those from Alaska — visit these warm waters to breed and birth and nurse their young.So Gabriele spends spring, summer and autumn studying humpbacks in Glacier Bay. Then, like the humpbacks, she winters in Hawaii, volunteering for two and a half months each year for the Hawaii Marine Mammal Consortium (HMMC), a non-profit organization that she co-founded in 2001. Hawaiian monitoring work proceeds while she analyses data and publishes research from her full-time Alaskan work.“Very few researchers who study humpback whales study them in both of their habitats,” says Gabriele. “I’m really glad to be one of those.”

    Members of the Hawaii Marine Mammal Consortium (HMMC) Holly Sargeant-Green, Christine Gabriele, Susan Rickards and Suzanne Yin (left to right) conduct research off the Kohala Coast of Hawaii Island.Credit: Lesley Evans Ogden, courtesy of Hawaii Marine Mammal Consortium

    The HMMC runs on a shoestring, and its boat was contributed by an anonymous donor. “We run on a lot of blood, sweat and tears,” says volunteer researcher Susan Rickards, an HMMC board member and school science teacher. Co-founder Adam Frankel is a bioacoustics consultant and Yin does ship-board observing of marine mammal populations.Routine’s rich rewardsIn both Alaska and Hawaii, “what we do tends to be fairly routine, simple, repeated research”, says Gabriele. “That has a lot of power, because we can detect change over time.” Over the years, she has investigated a wide range of questions in humpback biology, such as links between ocean temperatures and population trends. She helped to document the impacts of a marine heatwave11 from late 2013 to 2016 that led to a crash in the humpback population in Hawaii and Alaska2. In Alaska, she has also contributed to citizen-science and marine pilot-training programmes to mitigate the risk of whales being struck by ships.Much of her population work relies on photos of whale-tail markings to identify individuals. Since 2015, a machine-learning image-recognition algorithm known as Happywhale, pioneered by marine ecologist Ted Cheeseman at Southern Cross University in Lismore, Australia, has revolutionized humpback-whale identification. Gabriele is one of about 70 researchers who contributed photographic data to train this AI application, making individual identification faster and easier.

    Credit: Christine Gabriele, taken under NOAA Fisheries scientific research permit 26596

    Gabriele is “a great collaborator”, says Jan Straley, a marine biologist at the University of Alaska Southeast in Juneau who says it was a whale that ‘introduced’ them. Decades ago, a whale that Straley had photographed off the coast of southeast Alaska was spotted by Gabriele off Hawaii’s Big Island a little over a month later, and the photographic database of whale tails, geographical locations and observer names enabled the two to compare notes. Straley became a mentor to Gabriele as she embarked on work in Alaska. The two have since collaborated on many projects, including a database of whale sounds.Easy-going, calm and level-headed even in gnarly sea conditions, Gabriele “has your back”, says Straley. HMMC volunteer Holly Sargeant-Green agrees. “She doesn’t get rattled easily.” Sargeant-Green recounts how, when out on the water off Hawaii, Gabriele sometimes instantly identifies whales that she studies in Alaska from their flukes, with no AI required. “That’s pretty extraordinary,” she says.
    Racing across the Atlantic: how we pulled together for ocean science
    Conservation researcher Jo Marie Acebes saw this talent on the Alaskan side of the Pacific, noting that Gabriele “knew every single humpback whale we encountered just by looking at the dorsal fin or fluke”. Acebes, a long-time international collaborator of Gabriele, founded the non-profit organization Balyena.org based in Bohol, the Philippines, and is a senior researcher in the zoology division of the National Museum of the Philippines in Manila. After working remotely with Gabriele for years, Acebes fulfilled a lifelong dream of travelling to Glacier Bay National Park in 2022. Gabriele “is truly one of those scientists that have made great contributions to what we now know about humpback whales”, says Acebes. For example, Gabriele has tracked humpback pregnancy rates using hormone analyses4,3, and has documented how ship noise influences whale communication5.“It is not easy being a whale in today’s oceans,” says Gabriele, noting that one of the main aims of her research exploring their beguiling biology and behaviour is to work out how to decrease human impacts. “I feel very lucky to be a migratory biologist. I work in two of the most beautiful places on Earth. It’s such a privilege.”
    Quick-fire questions

    Can you tell us about some of the whales you see consistently in both places?
    Yes. One is a whale nicknamed Arpeggio, who is distinctive because he has a propeller scar on his dorsal fin. He and I hang out in Kawaihae Bay near Waimea, Hawaii, in the winter, and in Icy Strait in Glacier Bay, Alaska, in the summer. Given that I’ve seen only six whales I know from Alaska also appear in Hawaii — because humpbacks from all over the Pacific converge on Hawaiian waters — seeing Arpeggio three times is pretty remarkable.
    Do you ever see humpback mating battles?
    We’ve seen males jump on top of other males and look like they’re trying to drown them. Competition for mates can be pretty intense. Whales do all they can to escalate by threatening, which includes chasing each other, inflating their throats to appear bigger and cutting each other off from the object of their desire. But when it’s really getting serious, they hit each other. We’ve seen whales with their dorsal fin ripped halfway off. Whales also slash and scratch each other with their barnacled flippers.
    What’s an amazing thing that’s not well known about humpbacks?
    Their lifespan, which is similar to humans’. Their longevity was revealed from earwax layers accumulated over time. Working with collaborators, we showed that they live for around 60–80 years: twice as long as people had previously realized. Alternating light and dark layers of ear wax revealed that one whale captured during commercial whaling in Australia, which no longer occurs there but took place in the 1950s and 60s, was 96 years old.
    Do we have any idea what humpbacks are saying to each other?
    No. The presumed main audience is the females, but we have not decoded their messages. We do know that they use simple calls to stay in contact with one another and convey behavioural states such as excitement or aggression. They’re all singing the same song, but with individual and geographical variations of elements called themes. It’s as if you heard Frank Sinatra versus the Sex Pistols performing the song ‘I did it my way’.
    If you could speak whale, what would you say to humpbacks?
    If I had a chance to speak to a whale, I would want to apologize for what humans have done to the oceans that make their lives so much harder — creating so much dangerous shipping traffic, raising sea temperatures and producing all the marine debris that can dangerously entangle them. More

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    Lonely? Playful? Why are dolphin attacks rising in Japan?

    Male bottlenose dolphins can form lifelong partnerships with other males, and can spend hours chasing each other. Credit: Kirsty Nadine/Getty

    A spike in dolphin attacks has marred the tranquil beaches of Fukui Prefecture, Japan. As of 26 August, 18 people have been injured this year, taking the total number of casualties to 29 over the past 3 years, according to the Tsuruga Coast Guard Office. Injuries range from bites on the hand to broken bones.Researchers think the culprit is a single male Indo-Pacific bottlenose dolphin (Tursiops aduncus), on the basis of fin markings captured in photographs and video footage. Nature spoke to Tadamichi Morisaka, a dolphin ecologist at Mie University in Tsu, Japan, about dolphin behaviour and ways to prevent further attacks.Why might this dolphin be biting beachgoers?Gentle biting is a behaviour that we see often among male bottlenose dolphins in the wild. They do this to maintain the relationship — in this dolphin’s mind, he might have already built a friendly relationship with humans.We’ve seen that this dolphin randomly shows up at a beach, bites if there are people around, wanders off and repeats. To me, he’s seeking some kind of interaction with people. If he really wanted to attack, he could have come tackling at full force and chomped down. But he’s keeping the biting gentle for dolphin standards, so it’s probably a friendly gesture rather than a full-on attempt to attack.How does this behaviour relate to the social structures of Indo-Pacific bottlenose dolphins?Bottlenose dolphins typically live in pods. The males form lifelong partnerships with other males. Hanging out in pairs gives them better access to females, because two is stronger than one.These pairs spend hours and hours being playful with each other. This includes behaviours like chasing each other and rubbing the other dolphin with their pectoral fins — which is thought to signal fondness — and even sexual behaviours, such as pressing their penises against each other.Gentle biting is one of these pro-social behaviours. So the dolphin in Fukui is acting like he’s playing with a male pairmate, but with humans instead.Is it unusual for dolphins to be alone?That’s a mystery and an area that’s calling for further research. In the seas of Japan, we occasionally see individuals leaving the pod alone. But sometimes it’s females leaving, and sometimes they leave in groups of several individuals. The population closest to the beaches in Fukui is near Noto, Ishikawa Prefecture, but we’ve yet to identify whether the individual responsible for the attacks is from that population.How might the attacks change in future?We know that there are phases to human–dolphin interactions. It starts with humans and dolphins just sharing the same space. But as the interactions get deeper, the dolphins end up injuring humans. That’s where we are at in Fukui. If the interaction progresses to the next stage, dolphins can start asserting dominance through aggressive behaviours such as tackling or mounting people. We saw a bit of this last summer, so I was very concerned. They are about 2.5 metres long and weigh around 200 kilograms, so if they came charging at 20–30 kilometres per hour, it’d be like getting into a traffic accident. If they tackled us, it could break bones.What has been done to prevent further attacks in Fukui?Local authorities have placed underwater acoustic devices that play a variety of sounds at random. It’s not meant to elicit a specific response from dolphins, but probably sounds strange and annoying. But bottlenose dolphins could get used to this. They are a particularly curious species, so if they think there’s something intriguing enough, they’ll head to the beaches regardless of the sounds. In fact, we’ve seen the dolphin return to beaches that have these devices.I want to develop an early-detection system that can detect the echolocation they’re using for navigation. An alarm will go off as soon as we know dolphins are approaching. Once we’re able to get people out of the water in time, I think the dolphin will realize that there’s nothing interesting at the beaches, and eventually go back to its original environment. But, most importantly, we need to raise better awareness about what wild dolphins are like.What questions do you still have about dolphin behaviour?Much of my work focuses on dolphin acoustic communication, but you find lots of weird things going on when you observe them. Part of my mission is to interpret those behaviours scientifically — we’ve found that they yawn just like us, for example, and have wet dreams.These days, I’m curious about how they perceive the world. They ‘see’ using echolocation, but there’s a lot of unanswered questions about the role of their eyes. In dolphins, each eye moves independently, and they have two streaks in each of their eyeballs that give high visual acuity. Humans only have one point of high acuity. What, and how, could dolphins possibly be seeing with eyes like that? How is visual information integrated with echolocation and other auditory signals? Understanding their perception would help us to understand their society, because it forms the foundation of how they communicate — and that shapes their social structures. More

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    Local politicians have opened up Europe’s largest marine reserve for commercial fishing

    The Selvagens Islands Nature Reserve in Portugal’s Madeira region is Europe’s largest fully protected marine area, having been expanded in 2021 to 2,677 square kilometres, an area larger than Luxembourg (F. Alves et al. Nature 601, 318; 2022). But a decision by the regional authorities to reverse a commitment to ban fishing there puts one of the last intact marine ecosystems in the North Atlantic Ocean at risk (A. M. Friedlander et al. PLoS ONE 12, e0187935; 2017).
    Competing Interests
    The author declares no competing interests. More