Philippa Kaur

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

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

Nature’s Ghosts: The World We Lost and How to Bring it Back Sophie Yeo HarperNorth (2024)A century ago, the world’s first ‘wilderness area’ was established in the Gila Mountains of southern New Mexico, by the forester Aldo Leopold. He wasn’t concerned with preserving ancient wildlands or resurrecting a memory of the Pleistocene epoch. He wanted hunters to be able to take a two-week backpacking trip without encountering a road. Out of such pragmatic sentiments — and decades before the US Congress offered protections — grew a system of more than 800 wilderness areas on federal lands in the United States. Hundreds more have since sprung up worldwide.The wilderness is widely seen as a place untrammelled by human activities. Not so, argues journalist Sophie Yeo in Nature’s Ghosts. Advocating lyrically for rebuilding a diverse natural world, she recognizes that, however wild a region might seem, human activities have left a mark in even the most isolated regions. People have been a part of nature as long as they’ve been around, coevolving with its ecosystems for millennia.
Rewilding the planet: how seven artificial islands could help a dying Dutch lake
Take the English countryside. In A Child’s History of England (1852–54), novelist Charles Dickens perpetuates the narrative that the country was once covered in pristine forests and swamps, on which humans had little imprint until they acquired metal tools. Yeo dissects the deep flaws in this vision.Far from eking out an existence on the margins of vast forests, our forebears were reshaping the environment as soon as humans diverged as a species. Spiralling out from her home in England, Yeo explores such transformations by examining fisheries in Finland; restoration of wildwood in the Scottish borders; biodiversity-preservation programmes on small farms in Transylvania, Romania; and farming practices in Denmark and Greenland.In Finland, for example, fishers at lake Puruvesi have reclaimed rights to fish using conventional practices in areas that were usurped by the crown and state in the sixteenth century. By rebranding the vendace (Coregonus vandesius) — a small whitefish that was typically destined to be pet food — as a marketable delicacy, the fishers are providing a modern rationale for conserving an ancient landscape and way of life. For half of the year, the fishers drill through the ice and deploy large seine nets to scoop up the vendace from beneath the frozen surface of the lake.Ghosts of environments pastWeaving into her narrative an understanding of ecological niches, previous biodiversity crises and the deep environmental legacy of Roman farming, Yeo demonstrates the fallacy of trying to return the environment to any point in the past, whether that be pre-Roman Great Britain or Pleistocene Europe. Most continents — save for Africa, where large animals live on, and Antarctica, the surface of which has long been buried under kilometres of ice — are, as Yeo puts it, “haunted by the ghosts of the megafauna” that disappeared in the past 50,000 years, yet left an imprint on soil nutrients or made holes in ecological communities.

A bison in Wyoming.Credit: Paolo Picciotto/REDA&CO/UIG/Getty

She recounts how certain sharks in the Kiribati archipelago, white-tailed eagles (Haliaeetus albicilla) in Wales and beavers in California were regarded more as myth than reality, until careful work confirmed that those species once thrived in these regions. Those that remain often have to adapt to humans’ presence. The replacement of Bison antiquus in North America by Bison bison, or the succession of modern cattle from aurochs (Bos primigenius) in Europe, were marked by notable reductions in body size after centuries of evolving, interbreeding and hunting.The ecological legacies of human activities are pervasive and often subtle. Each environment has a history and preserves a record of its past. Part of Yeo’s mission is to show how these ghostly records should inform decisions about how best to recover some of nature’s past diversity as humanity moves towards a warmer and more uncertain future.
How to keep wildcats wild: ancient DNA offers fresh insights
An important point in her account is that there is no pristine baseline, devoid of human activity, to which restorers might retreat. For example, the woodland around the French commune of Thuilley-aux-Groseilles seems to be a remnant of an old-growth forest. But the enrichment of soils from Roman agriculture is evident in its plant communities, with buttercups prominent around houses and enclosures, and the broad-leaved helleborine (Epipactis helleborine) found in remoter areas.Yeo concludes that “the natural world has drifted so far from its origins that we no longer know what counts as natural”. It is impossible to establish what an area of land would have looked like or how it would have functioned before humans.Stuck in the presentYeo identifies three challenges for efforts to turn back history. First, as with the difficulty of identifying past white-tailed eagles in Wales, conservators often do not even know what is missing in an ecosystem, much less how they once worked. Second, climate change renders moot any effort to return ecosystems to how they were during, say, the seventeenth century, let alone the Pleistocene — and future conditions will differ from those now or in the past. Third, there are too many humans on the planet to leave substantial parts of it untouched.

White-tailed eagles (Haliaeetus albicilla) on a reserve in Wales.Credit: Getty

I am all in favour of continuing to repair the ecosystems of the Rocky Mountains in North America, by rebuilding populations of American bison, wolves, mountain lions (Puma concolor) and grizzly bears (Ursus arctos horribilis). But encounters with humans often end badly for these animals, imposing practical limitations to their reintroduction.Whereas people in low- or middle-income countries most affected by climate change and environmental degradation stand to gain the most from the restorations described by Yeo, the majority don’t have the luxury of considering rejuvenating nature. Although Yeo does not consider environmental justice and economic inequality as deeply as one might wish, she does recognize that the growing human population limits the opportunities for rebuilding now-vanished landscapes.
These animals are racing towards extinction. A new home might be their last chance
Yeo asserts that properly understanding the past can be a key to building a richer future, not by trying to rewind the tape of history to some pre-human idyll, but by reinvigorating the natural world in a way that is sustainable and enriches lives. This does not require humans to be banished from wild places.Yeo views nature as “fragile but tenacious”. Her vision is close to Leopold’s a century ago. After the Gila Wilderness was established, he realized that wilderness must be more than a refuge for hunters; the wolves and mountain lions that hunters killed were essential to functioning ecosystems.Nature’s Ghosts underscores how people have more choices than they realize when it comes to crafting a better future. The book rejects as false the dichotomy between urbanization and economic growth or untrammelled wilderness. Enriching landscapes and healthy ecosystems can coexist with building modern economies. But achieving this goal requires a deep knowledge of what has been lost and an appreciation for the resilience of species in the face of environmental tumult. Importantly, it requires acceptance that, although the future will not be a simulacrum of the past, a future with richer biodiversity is attainable. More

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Some orb-weaving spiders can hijack firefly mating signals to lure victims1.

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Conservation biology More

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Humpback whales (Megaptera novaeangliae) were hunted to near extinction by commercial whaling, their numbers have since resurged.Credit: Connect Images/Alamy

At the height of the whaling industry, thousands of whales were killed each year — mainly for their oil, a fuel used widely throughout the eighteenth and nineteenth centuries. By the 1930s, more people were becoming aware that whaling was unsustainable. In 1946, the International Convention for the Regulation of Whaling (ICRW) was signed, and the International Whaling Commission (IWC) was established as the decision-making body to deal with the problem. It was the world’s first global convention designed to address a significant threat to wildlife.The IWC will hold its 69th meeting in Lima in September. As the convention nears its 80th anniversary, we propose that the IWC hands over several pending issues to other conventions and national governments and closes up shop.The IWC’s accomplishments — managing global whale populations and especially implementing a moratorium on commercial whaling in 1985 — are laudable. But these achievements lie four decades in the past. IWC meetings since have been a source of acrimonious and fruitless dialogue among member nations. By exiting with dignity, the IWC would set a powerful example for the international environmental community.A bright beginningThe ICRW was originally established to deal with the “conservation of whale stocks and … the orderly development of the whaling industry”. Conservation in this context meant ensuring that enough whales were protected so that some could be harvested sustainably. But as it became clear that most species were in severe population decline1, the IWC decided in 1982 that commercial whaling for all species everywhere should cease from the 1985–86 season onwards2.The agreement was groundbreaking in its ambition. It led to the near-total cessation of whaling activities, with a few notable exceptions (see ‘Where whaling still goes on’), and has contributed to the resurgence of many whale species, including the largest animal on Earth, the blue whale, Balaenoptera musculus (see ‘Making a comeback’).
Where whaling still goes on

A moratorium implemented by the International Whaling Commission (IWC) has stopped almost all commercial whaling since 1985.
Some Indigenous populations, mainly in the Arctic, are permitted to harvest whales2. And Article VIII of the International Convention for the Regulation of Whaling — arguably a legal loophole that enables commercial whaling to persist — allows governments to “grant to any of its nationals a special permit … to kill, take and treat whales for … scientific research”10,11. Japan’s use of provisions of this article1 (since 1991) prompted Australia to take Japan to the International Court of Justice in 2013.
But today, only three nations still have commercial whaling operations: Norway, Japan and Iceland. In the 1980s, Japan agreed to the moratorium with the provision that it would be “kept under review, based upon the best scientific advice”, and that “by 1990 at the latest the Commission [would] undertake a comprehensive assessment of [its] effects”2. In 2018, however, the nation announced that it would leave the IWC and become an observer state, meaning that its IWC representative would attend meetings but not vote. And in 2019, Japan re-commenced whaling operations in its exclusive economic zone. Norway and Iceland, through legal reservation, do not abide by the moratorium.

This is a huge achievement. But in the years since, the convention has done little to help conserve the great whales (including the gray, humpback, right, sperm, bowhead and minke whale), or encourage the sustainable harvesting of their populations.The number of ICRW member nations (many of which have never whaled) has ranged from around 30 in 1990 to nearly 90 today. After the moratorium on whaling was established, many IWC government members were not prepared to revisit it; work on a ‘comprehensive assessment’ to evaluate the impacts of the moratorium has proceeded at a snail’s pace; and two attempts to reform the convention and achieve further useful outcomes from it failed2. Meanwhile, despite decades of discussion, the IWC has had virtually no impact on the whaling that has persisted since 1985. Indeed, none of the nations with limited whaling programmes — Norway, Iceland and Japan — engage in any meaningful way with the convention.Despite the IWC having so little to show from the past four decades of operations, participants and observers continue to meet — once every two years since 2012, rather than annually. And the IWC continues to absorb the time, energy and resources of its members and engaged civil-society organizations. A dispute that began at the IWC but ended up in the International Court of Justice in 2013, for example, involving the Australian and Japanese governments, cost more than Aus$20 million (US$13 million) but had no discernible impact on whale conservation.

Source: IWC

Exit with dignityToday, the IWC should celebrate its accomplishments, devolve its final responsibilities and send a powerful message about the importance of knowing when to stop.Indigenous Arctic communities have continued to hunt whales for sustenance3, with quotas being set by the IWC since 1983 having no discernible effects on whale populations. Even so, in the coming decades, subsistence whaling must be managed effectively, with quotas for each Indigenous group being allocated on the basis of scientific evidence. If the IWC no longer existed, each country could manage their own subsistence whaling. Indeed, Target 5 of the Kunming–Montreal Global Biodiversity Framework, which 196 countries have agreed to meet by 2030, is to “ensure that the use, harvesting and trade of wild species is sustainable, safe and legal … while respecting and protecting customary sustainable use by indigenous peoples and local communities”.Similarly, the whaling currently undertaken by Japan, Norway and Iceland — in each nation’s exclusive economic zone, and of species whose populations are currently stable — does not need oversight from almost 90 nations.Some people might argue that letting countries regulate and manage their own whaling in their own waters could result in a resurgence of large-scale commercial whaling. We think that this is extremely unlikely, not least because of the lack of demand for whale products (oil and meat) and changing attitudes around wildlife. What’s more, several other conventions can provide protection against such a scenario.

Japan, Norway and Iceland still conduct commercial whaling.Credit: Getty

The Convention on International Trade in Endangered Species of Wild Fauna and Flora (CITES), for example, regulates international trade of endangered wildlife4. All whale species regulated by the IWC are included in CITES Appendix I, a list of the most endangered species. Therefore, international trade of these species is prohibited. All other whale species are included in CITES Appendix II, which means international trade of all cetacean products is regulated. Similarly, the Convention on the Conservation of Migratory Species of Wild Animals (CMS), which already conserves small cetaceans in some regions, such as dolphins and porpoises, could also conserve whales. In fact, the scientific body of the CMS (the Scientific Council) could function, in part, as a global whale observatory, and alert the world to negative trends in any species. Today, the biggest threats to whales are ship strikes, pollution and climate change.Consolidate and streamlineMore than 3,000 international environmental agreements and organizations exist today5. Some of these, such as the Montreal Protocol on ozone depletion, have achieved their goals or are close to doing so. Other initiatives have struggled to achieve much6. Today, the many institutions that have had little impact collectively expend millions of dollars annually on secretariats and meetings, and use up time and resources from governments and civil-society organizations.
Conservation interventions are effective but far from sufficient
In our view, various broader international conventions could be used in place of other wildlife conservation agreements. The United Nations Framework Convention on Climate Change, for example, could take over the residual tasks of the Montreal Protocol. The Convention on Biological Diversity could similarly achieve the goals of the 53-year-old Convention on Wetlands7. (In fact, the Convention on Conservation of Nature in the South Pacific suspended operations in 2006 for exactly this reason.)Such consolidation would increase efficiency and effectiveness. Indeed, we urge this issue to be included as a key agenda item at the upcoming UN Summit of the Future, an event focused on how world leaders can safeguard the future, which will take place in New York City in September.In 2018, political scientist Julia Gray at the University of Pennsylvania, Philadelphia, defined an international convention or organization that consumes time, energy and resources without generating added value as a zombie institution8. Such institutions project the illusion of solving problems even when they persist, or of problems persisting even when they no longer exist9. Zombie organizations undermine the very idea of multilateralism, in which multiple countries form an alliance in pursuit of a common goal. Proud legacies and historical achievements are important. But allowing institutions to become zombies serves no one. More

Scientists attached cameras and sensors to small pieces of neoprene that they glued to the sea lions’ backs.Credit: Nathan Angelakis

Footage captured by sea lions wearing lightweight video cameras is giving researchers a glimpse of previously unexplored areas of the sea floor off the south coast of Australia.The findings, published on 7 August in Frontiers in Marine Science1, include detailed maps of the ocean floor created by combining videos captured by the animals with a machine-learning model. The camera footage also reveals details of how different habitats and species are distributed.“These are particularly deep and remote offshore habitats that you can’t get to by usual surveys that you would conduct from a boat,” says co-author Nathan Angelakis, who researches ecology and evolutionary biology at the South Australian Research and Development Institute in West Beach. “With the data we’re collecting, we’re essentially exploring new parts of the ocean that haven’t been mapped”.Uncharted watersUnderstanding the layout of the sea floor is important for several reasons, including marine conservation, navigation and predicting hazards such as tsunamis. “You can’t manage what you haven’t measured,” says Steve Hall, head of partnerships at the ocean-mapping organization Seabed2030, which is based in Liverpool, UK.
This AI learnt language by seeing the world through a baby’s eyes
Worldwide, just 26% of the sea bed has been mapped at high resolution. This is partly due to the challenges associated with exploring the deep sea, where pressure is extremely high and light levels are low. Researchers typically map the sea bed using remote-operated underwater vehicles or by dropping cameras from surface vessels — but both of these methods are time-consuming and costly.Angelakis and his colleagues trialled a comparatively low-tech approach by enlisting the help of wild Australian sea lions (Neophoca cinerea). These animals spend most of their time on the sea bed, foraging for food across the continental shelf, the section of the ocean that extends from the coastline. The researchers theorized that by tracking the sea lions’ movements, they would be able to gather information about both the shape of the sea floor and the distribution of different habitats.The authors attached sensors to neoprene patches that they glued to the backs of eight adult females from two of the largest Australian sea-lion colonies. The equipment, which included GPS trackers, cameras and motion sensors, was designed to be small and non-cumbersome, weighing less than 1% of the sea lions’ body weight, so as not to hinder the animals or affect their behaviour. On completion of the project, team members were able to remove the sensors from the patches without damaging the sea lions’ fur.

Together, the sea lions captured 89 hours of footage that took in six distinct sea-floor habitats, from bare sand to meadows of algae.The researchers used the footage to assess biodiversity in these areas, and to compare the locations visited by the two colonies. They also used the videos to check the accuracy of a machine-learning model designed to predict the sea-floor habitat from variables such as sea-surface temperature and distance from the coast. This revealed that the model was more than 98% accurate, so the researchers then used it to map sea-floor habitats in surrounding locations. “One of the real powers of the study is taking the data we collected to predict other unknown areas,” says Angelakis.The team also wants to use the sensor data to explore how factors such as depth and nutrient supply affect habitat distribution and biodiversity on the sea floor. This could help researchers to further explore “the ecological value of different habitats and marine areas to sea lions”, says Angelakis, which could boost conservation efforts.Using sea-lion-mounted sensors is a “very nice way of getting high-resolution data from a hard-to-get-at place”, says Hall. He suggests that in future studies the researchers could equip the sea lions with extra sensors to gather data on the physical and chemical properties of sea-bed habitats. More