Philippa Kaur

Observations of birds are relatively scarce in neighbourhoods that were redlined, or designated as risky for mortgage lending, in the 1930s.Credit: George Rose/Getty

Ecologist Diego Ellis-Soto has plenty of local bird data to study. On the university campus where he works, more than half a million bird sightings have been recorded over the past century. But Dixwell, a neighbourhood just down the road, has totalled just a few dozen bird observations in the same period.“I could go there one day and double what’s been collected in the last 100 years,” says Ellis-Soto, who’s at Yale University in New Haven, Connecticut. It might be no coincidence that Yale’s students and faculty are mostly white — in contrast to Dixwell, which has a high proportion of residents who are Black.The disparity in recorded bird sightings doesn’t affect just New Haven. An analysis1 by Ellis-Soto and his colleagues shows that data on bird biodiversity are scarcest in US neighbourhoods, such as Dixwell, that have historically been subjected to certain racially discriminatory policies. This lack of information could affect scientists’ understanding of how birds are distributed in US cities and how species fare over time.Red zones for real estateIn the 1930s, a US-government-led effort graded urban neighbourhoods across the country on whether they were ‘safe’ for real-estate investment. Areas that were judged to be the safest bets for investment were rated ‘green’, and those judged to be highest risk were rated ‘red’. Grades were determined, in part, by a neighbourhood’s racial composition. This categorization, now called redlining, drove investment in wealthier and white neighbourhoods. It also led to a lack of investment in poorer areas and in neighbourhoods of colour.
Landmark Colombian bird study repeated to right colonial-era wrongs
To study how redlining has affected biodiversity assessment, Ellis-Soto and his team studied bird sightings in more than 9,000 neighbourhoods, covering almost 200 US cities. They found that there were many more bird observations per square kilometre in green districts, whose residents are in many cases still predominantly white, than in redlined districts, whose residents are mainly people of colour.“You can better predict where you have data on birds based on systemic racism — redlining maps from 1933 — than climate, tree cover or population density, everything a bird should actually care about,” Ellis-Soto says.From 2000 to 2020, the density of bird observations rose steeply in green neighbourhoods, but more gradually in red ones. The disparity in observations between green and red zones grew by more than 35% in that period, the authors calculate.The study is one of the first direct looks at how “systemic racism can play a role in the ecological process”, says Jin Bai, an urban ornithologist at North Carolina State University in Raleigh.Missing data, missing fundsData on biodiversity constitute the “first building block” for distributing funds to protect wildlife, says Ellis-Soto. Without data to show their ecological importance, redlined areas could be passed over for funding — widening historical inequalities.“It’s essentially this self-perpetuating negative loop,” says Chris Schell, an urban ecologist at the University of California, Berkeley. “You have more observations of a native species in an environment that already has a ton of money. Then that same neighbourhood gets more money to conserve a species, which makes it more exclusive, which makes housing more exclusive, which then continues the legacies of segregation.”Ellis-Soto says the gap in data is due, in part, to biases held by scientists and birders, who tend to survey the same areas repeatedly. A lack of resources for teaching birding and for recording observations in historically marginalized areas also contributes.Ellis-Soto would like federal funding for such education efforts. But in the meantime, he takes Black and Hispanic kids from New Haven for nature walks and teaches them how to log the birds they see. “That’s my little solution,” he says. More

Several pieces of legislation that are under consideration in Colombia threaten to change the country’s research landscape if passed, by banning almost all science and education using live animals. Although one bill introduced in Colombia’s Chamber of Representatives has already been rescinded after backlash from scientists, a second bill and a constitutional amendment remain active in the Senate.“Science hasn’t always been supported by politicians in Colombia, but I don’t think any of us saw this coming,” says Nataly Castelblanco-Martínez, an aquatic-mammal biologist at the National Council for Science and Technology in Mexico, who is originally from Colombia and frequently collaborates with scientists back home. “No one is saying we don’t need regulation, but together, [these bills] affect virtually everything we do as researchers.”A rising movementColombia is one of the world’s most biodiverse countries. After a civil conflict that lasted more than 50 years and limited where scientists could travel, researchers resumed chronicling wildlife and establishing conservation plans. But there are many understudied species, and in recent years, an ‘animalist’ movement has developed in Colombia that threatens scientists’ work.
Expeditions in post-war Colombia have found hundreds of new species. But rich ecosystems are now under threat
The bill that has since been withdrawn from the Chamber of Representatives — which hosts a number of politicians who are sympathetic to animal-welfare causes — had stated that “in no case may wild animals be used in education or biological studies”. After scientists raised the alarm, at least four members of the Colombian Congress pulled their signatures. In an e-mail to Nature, the bill’s author, Juan Carlos Lozada Vargas, said that he ultimately withdrew it “to create a space of trust” with scientists. And he has been visiting researchers in various institutions since then.Some scientists say that ‘animalists’ are taking advantage of the closure earlier this year of a malaria research facility in Cali, which had been funded by the US National Institutes of Health, to push through more restrictive animal-research policies. The animal-welfare organization People for the Ethical Treatment of Animals (PETA) unearthed evidence of alleged animal abuse at the laboratory.At the same time, there’s an ongoing debate over how best to manage a population of invasive hippos accidentally introduced into Colombia after they escaped from the drug-cartel leader Pablo Escobar’s estate outside Medellín. The hippos, biologists say, threaten native species, and their population must be reduced. Others, however, are protective of the hippos and the benefits they bring through tourism. The Animal Legal Defense Fund, an organization that advocates for the rights of animals, filed a lawsuit against the government over its efforts to control the hippos, and Colombian senator Andrea Padilla Villarraga recently introduced a draft constitutional amendment that would recognize animals as people, with commensurate legal protections.Researchers note that granting personhood to something like an invasive species would be a dangerous precedent that ignores the damage a single species can do to an entire ecosystem. In an e-mail to Nature, Padilla Villarraga rejected this argument. “Does environmental protection conflict with the protection we owe to other animals as sentient individuals?” she asked. “It is a false dilemma to think that you have to choose between one and the other.”Research transformedPadilla Villarraga is also the author of the pending Senate bill that would curtail animal research and overhaul the country’s ethical-approval process. The bill states that “the use of live animals in academic and scientific research, toxicity-testing studies, biological or related studies” is prohibited when the results can be obtained “by other means” or when using “live animals of a higher grade on the zoological scale”. Scientists say that they take this to mean animals with greater cognitive capacity or sentience, but that the vagueness of the bill makes it challenging to interpret.

Carlos Daniel Cadena Ordoñez handles a white-breasted wood wren (Henicorhina leucosticta) captured for research purposes using a mist net.Credit: Guillermo Gómez

Carlos Daniel Cadena Ordoñez, the dean of the school of science at the University of the Andes in Bogotá, says that larger institutions in cities might be able to meet these new requirements, but that smaller, more rural ones probably won’t. “There are all these barriers to science, and now we’re going to put more barriers that are going to make it even more exclusionary,” he says.
Landmark Colombian bird study repeated to right colonial-era wrongs
Beyond the damage that the legislation would do to research, it would change the way in which students are educated. The bill states that undergraduate students cannot interact with animals until their last two years at university, and then only under supervision. “But all the research that I do, I do with students,” says Andrés Cuervo, an ornithologist at the National University of Colombia in Bogotá, who focuses on avian biodiversity. “We need to put these people out there in the field right away.”The Senate bill would also effectively shutter the conservation work of Ana María Morales, a wildlife biologist at the Eagles of the Andes Foundation, a bird-rehabilitation centre in Pereira. She observes endangered black-and-chestnut eagles (Spizaetus isidori), and sometimes captures and tags them. Animals that cannot be released are used to educate the public and to train professionals on proper handling techniques. “As the only raptor rehabilitation centre in Colombia, we are the ones that have this information, and this bill will prevent us from sharing it,” she says.A tense waitThe likelihood of the bill passing remains unclear. Cuervo says that it has a good chance of making its way to President Gustavo Petro, and that it could be signed by the end of the year. But others, including Cadena Ordoñez, think it’s unlikely to pass, given the reaction to the withdrawn Chamber of Representatives bill. However, “we have to act as though it will, because a lot of people will be out of work if this bill goes through,” he says.The threat has prompted Colombian scientists to organize. What began as a WhatsApp chat among concerned biologists has grown into a group called Biodiversos that currently has more than 2,750 members. Castelblanco-Martínez, who is a member, says that the group has been largely reactive — putting out statements in opposition to the bills — but that is changing: members recently attended a forum with Padilla Villarraga to outline their concerns. “The fact that we’re coming together, all working towards the conservation of our resources, it’s really great,” she says. More

Oceans are warming up, and dangerously so. Since April this year, the average global sea surface temperature has been unusually high and rising; by August, oceans in the Northern Hemisphere had reached record-high temperatures, even surpassing 38 °C in one area around Florida.These extreme temperatures, fuelled by the climate crisis, have manifested as a series of marine heatwaves — periods of anomalously warm sea temperatures that can last for weeks, months or even years — across the Northern and Southern hemispheres. In some areas around the United Kingdom and Ireland, for example, surface waters in June and July were 4–5 °C warmer than is usually recorded at this time of year. Temperatures are also soaring off the coast of Florida and into the Gulf of Mexico, extending across the tropical Pacific, around Japan, and off the coasts of Ecuador and Peru. Marine heatwaves are more intense, last longer and occur more frequently than they used to. From 1925 to 2016, the number of days classed as experiencing marine heatwaves increased by 54%1.This makes the concurrent likelihood of a strong El Niño — a climate phenomenon that is typically associated with a rise in global temperatures — particularly worrying.Marine heatwaves disrupt, threaten and damage ecosystems. They are particularly dangerous for temperature-sensitive organisms that live in cool waters, such as kelps, and immobile warm-water organisms, such as corals. Many species might be susceptible to disease or mortality, with knock-on effects. For example, in 2014–15, a marine heatwave off the west coast of the United States, dubbed the Blob, caused widespread loss of sea stars. This in turn caused a bloom of sea urchins (on which sea stars predate), which in turn damaged kelp forests2. Rising water temperatures can also cause some species to migrate to cooler waters.Such events also affect local communities, including through economic losses from impacts on fisheries and aquaculture. The Peruvian anchoveta (Engraulis ringens), for example, disappears from its usual fishing grounds during marine heatwaves. In 2015–16, the sea off eastern Tasmania in Australia saw high mortality rates for oysters and abalones during a warm spell. And although tourism has played a part in the degradation of corals, mass bleaching of coral reefs also dents tourism, because white corals do not appeal to snorkellers and divers. The impact of a heatwave on marine industries can run into billions of dollars3.

An autonomous glider is deployed into the Indian Ocean to monitor marine conditions.Credit: Suzanne Long/Alamy

Given the impending overlap of El Niño conditions with long-term warming trends, it is pressing to closely monitor regions with a high likelihood of marine heatwaves, and to develop and implement a range of approaches for reducing risks to wildlife and economies. Here, we urge decision makers in marine and coastal biodiversity conservation, fishing, aquaculture and tourism industries to devise such a strategy for the coming months as well as for the decades ahead. We set out four priorities.Identify threatened regionsWhere communities are prepared, impacts can be mitigated, at least partially. This depends on knowing which regions are most likely to be affected.An analysis of historical data can reveal which areas experienced marine heatwaves during previous El Niños, and suggests where such events are most likely to occur when it develops: in the northeast Pacific (affecting coastal waters from California to the eastern Bering Sea); the tropical central-to-eastern Pacific and the shelf waters of Ecuador and Peru; off eastern Australia; and the Indian Ocean, including off the east coast of Africa, southern India, and southeast Asia (see ‘El Niño and marine heatwaves’ and Supplementary information). These areas are known to be susceptible to mass die-offs of diverse marine habitats, from tropical coral reefs to temperate kelp forests4.

Source: Analysis by A. J. Hobday et al. based on data from marine.copernicus.eu; see Supplementary Information

El Niño occurs as part of a cycle (see ‘What is El Nino?’), but this is not the only climate cycle to influence marine heatwaves. Other ocean and atmospheric patterns operate on timescales ranging from a few years to several decades. These manifest as natural variations in temperature in different ocean basins5. For instance, the current negative phase of the Pacific Decadal Oscillation is associated with warming waters around Australia, the northwest Pacific, the northern Indian Ocean and parts of the South Pacific and South Atlantic. In the next few months, a positive Indian Ocean Dipole is also predicted to start to warm the western Indian Ocean. This pattern, reinforced by El Niño,typically brings a warm and dry summer for many parts of Australia.
What is El Niño?

Short-term patterns in global climate such as El Niño are superimposed on long-term anthropogenic warming, with serious consequences predicted for many regions of the globe.
The El Niño–Southern Oscillation is a major climate phenomenon that comprises a warm phase (El Niño), a cool phase (La Niña) and a neutral phase. These switch, irregularly, every few years. El Niño — when winds over the tropical Pacific falter and the warmest waters in the western Pacific flood eastwards, disrupting the entire atmospheric circulation — has the most widespread impact on sea surface temperatures globally.
For the past three years, the world has been experiencing La Niña conditions, associated with cooler global temperatures and cooler-than-average sea surface temperatures in the central and eastern tropical Pacific. Earlier in 2023, conditions in the tropical Pacific began to reverse and El Niño seems to be developing. It is likely to amplify until the end of this year and possibly into next year as well, and is poised to trigger major marine heatwaves.

There are counter trends, too — although El Niño drives rising temperatures in many areas, it suppresses the likelihood of marine heatwaves in a few regions, including the waters off Papua New Guinea, New Zealand, the Philippines and western Australia.Although our understanding of marine heatwaves has lagged behind that of their atmospheric counterparts, researchers have learnt a great deal about these extreme events since the last El Niño. A better grasp of how different climate cycles are connected, as well as their influences, will aid preparations.Improve forecasts and warningsWork is progressing on predicting spikes in seawater temperatures6. Ocean weather forecasts are reliable a week or so in advance7, probabilistic seasonal forecasts give indications several months ahead8,9, and centennial-scale climate projections that take into account anthropogenic greenhouse-gas emissions provide the longest view10.Spatial maps showing probabilities of marine heatwaves are most accurate in open oceans where climate drivers, particularly El Niño, are strongest, and less so nearer coasts, where local ocean and atmospheric conditions become important. Building predictive power for these regions — by improving coupled ocean–atmosphere models and assessing the accuracy of their predictions — is crucial for local biodiversity conservation efforts as well as the fishing, aquaculture and tourism industries.Plan local responsesThis year, countries such as Australia and the United States are using seasonal-scale early warning systems, with lead times of several months, to provide marine-heatwave briefings to conservation agencies, the fishing and aquaculture industries, and the public.Options to alleviate potential impacts or improve recovery after a marine heatwave vary by industry (see ‘Managing marine heatwaves’ and Table S1 in Supplementary information). These steps depend on the marine environment and the species or ecosystems of concern, as well as on the expected timing, severity and spatial extent of the forecast event.

Source: Adapted from A. J. Hobday et al. Prog. Oceanogr. 141, 227–238 (2016) and https://go.nature.com/45UXWBP

In the case of marine heatwaves predicted to develop in winter and spring, when waters are generally coolest, aquaculture industries might need to change the feed mix for species such as salmon, prepare for disease outbreaks, or change the time of harvest to ensure animals are in prime condition. For summer and autumn events, when temperatures exceed the coping range for many species, fisheries might need to reduce catch limits or close an area altogether, to enable species to cope with the stress of warmer waters. Without such interventions, marine heatwaves can result in reduced catches for several years, as was seen in crab and scallop fisheries off western Australia following a 2011 event.Changes in the distributions of species could also challenge jurisdictional management for fisheries. For example, when mackerel and squid moved from southern to northern Californian waters in 2016, quota management, employment and market prices were affected.

A kelp forest near Santa Barbara Island, California.Credit: David Fleetham/Nature Picture Library

The fishing and aquaculture sectors can shift harvesting and production schedules to maximize yield before temperatures rise, move inactive fishing vessels to cheaper moorings and reduce seasonal staff hiring in regions where activities are poised to decline. Other management strategies might include delaying restoration of kelp and seagrass in previously affected areas when further marine heatwaves are forecast. Innovative approaches, such as restoration that introduces species adapted to warmer conditions or the temporary alteration of clouds to protect coral reefs from solar radiation, need to be investigated.Some tourism enterprises, such as diving or snorkelling firms, might reduce numbers of staff during marine heatwaves, or modify their activities to minimize job losses. Whale-watching trips could be increased, for example, as happened off the coast of San Diego, California, during the Blob. Sports-fishing companies should ensure they have the appropriate permissions, equipment and staffing when warmer-water species move to areas where they are not usually seen.Monitor impacts of warmer watersFor the scientific community, warnings months ahead of likely rises in temperatures provide the opportunity for in-depth studies. Hypotheses can be developed and tested, data can be gathered — for example, by using underwater gliders to determine the vertical structure of heatwaves — and samples can be collected and analysed.

A sunflower sea star (Pycnopodia helianthoides; right) and red sea urchins (Strongylocentrotus franciscanus) off southeast Alaska.Credit: Jeff Mondragon/Alamy

To better understand ecological responses to extreme warming events, researchers should scale up monitoring efforts to characterize a region’s physical and biological conditions before a heatwave’s onset. They should deploy sensors to measure key variables (such as temperature, oxygen levels, salinity, and the abundance and composition of nutrients and plankton) across multiple scales in time and space and at high resolution, from the surface to deeper waters. Although intense sampling during an extreme event provides a wealth of information, robust characterization of an ecosystem before a heatwave is also crucial, to provide a baseline. Data should be collected to assess changes in habitat types as well as the growth, reproduction and survival of species.A wide range of approaches, including remote sensing (such as for monitoring phytoplankton), fisheries surveys (to assess changes in fish distribution and abundance, for example), environmental DNA collection and citizen science (for detecting species outside their normal ranges) can help. Indigenous and local communities might notice early changes in the environment and should lead monitoring and planning endeavours.Predictions of which species or habitats will be affected by a marine heatwave, on the basis of existing information or ecological theories, will allow hypotheses to be tested — such as the idea that impacts are greatest in the warm part of a species’ range. Species that can survive only in a narrow range of temperatures, such as tropical corals, and those living close to their thermal limits, can serve as indicator species for wider impacts.

A green sea turtle (Chelonia mydas) swims near an algal bloom off Tenerife in the Canary Islands.Credit: Sergio Hanquet/Nature Picture Library

Oceanographic survey tools such as gliders and autonomous underwater vehicles should be deployed to sample the evolution of marine heatwaves. They can record a range of data, including on temperature and salinity but also levels of ocean acidification and of oxygen and nitrogen, to better understand environmental change. Where threatened species or populations might be affected, being able to collect and ‘biobank’ samples to preserve genetic diversity would be an important step for further research and subsequent restoration.Worryingly, the climate crisis could eventually cause oceans to reach a permanent heatwave state relative to historical baselines11, and some regions might no longer support certain species and ecosystems. The ecosystems that emerge might not operate and respond to warmer waters in ways that can be anticipated12. Scientists might not be able to prevent these consequences, but it is crucial to devise and implement adaptive strategies to keep them at bay temporarily or soften their impacts wherever possible. This could buy time for species and ecosystems, and the industries that rely on them, to adjust and transform9.Regardless of whether a full-blown El Niño event occurs this year, these preparations will aid many marine businesses, because all projections indicate that more-frequent, stronger and longer-lasting marine heatwaves are inevitable in the near future. More

Humanity and some of the world’s most charismatic wildlife are on a collision course in the oceans.The world’s merchant fleet — from oil tankers to bulk cargo carriers and container ships — has doubled in size in just 16 years to more than 100,000 vessels, according to United Nations figures (see ‘A fast-growing fleet’). Between 2014 and 2050, shipping traffic is expected to rise by up to 1,200%1.These numbers, combined with data on where shipping networks overlap with the movements and aggregations of marine animals2,3, together with assessments of the effects of ship strikes on certain marine species, present an increasingly alarming picture. They suggest that ship strikes could be helping to drive the population decline of many animals, leading to profound effects throughout their ecosystems, for instance by altering biogeochemical fluxes4.

Source: UNCTAD

Yet compared with other threats to marine biodiversity, such as climate change and pollution, the problem of ship strikes harming wildlife is tractable. Various technologies and approaches are increasingly enabling surveillance of both ships and wildlife. Global regulation of the shipping industry has already been established to limit greenhouse-gas emissions. And various schemes to reduce strikes have proved effective in some locations for certain species.What’s needed now are four changes. First, researchers require better data on where, when, how often and for which species strikes are occurring. Second, there must be greater engagement with the problem, both from the shipping industry and the public. Third, regulations should be brought in to either reduce ship speed in certain areas or reroute vessels; and finally, there must be monitoring of adherence to such restrictions. With these changes, there is no reason why this problem cannot be addressed.Tip of the icebergCollisions between ships and ocean animals are hard to quantify because they are not systematically recorded, and can go unnoticed when large vessels are involved. Carcasses can sink before they are observed.Numerous lethal strikes have been documented worldwide in the past 100 years or so, often by scientists using eyewitness accounts or by direct observations of floating, dead animals2,3. Researchers have been warning of the impacts of global shipping on whales for nearly two decades5. And for some species, research has established the importance of ship strikes relative to other threats. A 2019 study, for instance, showed that, alongside entanglement in fishing gear, ship strikes are a leading cause of human-induced mortality for the critically endangered North Atlantic right whale (Eubalaena glacialis)6.

An acoustic monitoring buoy.Credit: Woods Hole Oceanographic Institution

By collating information dating back to 1877 on what species have been struck by vessels, a 2020 study identified more than 75 marine species as being at risk of harm from strikes2. The marine megafauna — whales, sharks, sea turtles and other organisms with a body mass of 45 kilograms or more — top the list. These ocean giants spend most of their lives at the surface3, travel hundreds or thousands of kilometres across ocean basins and often aggregate in coastal and continental-shelf areas7.The list includes some of the most endangered animals: 60 are on the International Union for Conservation of Nature’s Red List of Threatened Species2. More than one-third of those listed are threatened with extinction. For the other 15, there are insufficient data to make an assessment.
UN high seas treaty is a landmark – but science needs to fill the gap
Studies on ship strikes so far, however, are not comprehensive and have drawn on data collected only from particular areas and only for some species. According to conservative estimates based on deaths of three whale species in four US study sites, for example, ships kill more than 80 whales a year in an area measuring roughly 800,000 square kilometres8. Yet for other species, data on the number of deaths and the location of collisions are missing. Reports of strikes tend to focus on a few species that are most likely to be seen floating when dead, such as whales, dolphins and turtles. But the majority of marine animals, and all cartilaginous fishes (sharks, rays, skates and so on), sink when dead and so will not be observed2.A 2022 study co-authored by two of us (F.C.W. and D.W.S.) attempted to assess the global impact of collisions on whale sharks (Rhincodon typus), a species that sinks quickly when dead3. The findings are concerning. Satellite data that tracked the relative positions of whale sharks and vessels show that 92% of the species’ use of horizontal space and nearly 50% of its vertical space use overlaps with shipping routes. Strikes could explain why the population is continuing to decline even though mortality caused by fishing has been reduced.In short, various lines of evidence indicate that existing records of ship strikes — and the estimates made so far of the impact of collisions on marine life — represent the tip of the iceberg for current and future harms of the shipping industry to marine biodiversity.Data on demandFortunately, the tools and key players needed to collect and analyse data across ecosystems and jurisdictional borders — and to develop mitigation strategies — already exist.Various international projects are already collating and distributing data on where animals are and how they move through the ocean. These include platforms that rely on surveys, such as the Ocean Biodiversity Information System; animal-tracking databases such as Movebank; and tools that predict animal distributions on the basis of sightings and assessments of habitat suitability, such as AquaMaps.Likewise, shipping information can be obtained from providers of Automatic Identification System data, which use satellites to track vessels, as well as from ocean-monitoring initiatives such as Global Fishing Watch and from the US National Oceanic and Atmospheric Administration (NOAA).

A shortfin mako shark (Isurus oxyrinchus) with satellite tags in the Pacific Ocean.Credit: Mark Conlin/Alamy

Using such data, whale experts and other researchers have already started to pinpoint high-risk areas2,3 (see Supplementary information). Our work on whale sharks showed that one is the Strait of Hormuz between the United Arab Emirates and Iran, through which about one-third of global maritime-traded oil passes each year (see go.nature.com/47kjric).For many species, this information is not yet available. Also, data collection is often patchy and disparate, with animals being tracked only in part of their range, and various data-gathering approaches being used in different areas.Governments, industry and philanthropic and other organizations can help to fill the gaps by bolstering pre-existing projects. Various mobile-phone app and web-based initiatives are leading the way with technology-powered mapping and analysis. For instance, the Whale Safe tool uses various measures, including public whale sightings, to help establish voluntary speed restrictions and other actions to reduce the risk of strikes. The use of low-Earth-orbit satellites to monitor large marine animals from space — currently an untapped technique — could provide researchers and other stakeholders with near-real-time, actionable data for high-risk areas9.But efforts must be scaled up, with those involved in local and regional projects facilitating the establishment of similar initiatives in other parts of the world, particularly in the global south. Existing efforts to connect projects and partners associated with the ocean will be key. Since 2021, for instance, the United Nations Decade of Ocean Science for Sustainable Development programme has been connecting people and organizations concerned with the role of kelp forests and seagrass beds in storing carbon, among many other issues.Increased engagementIn the past few years, it has become increasingly common for commercial shipping companies to disclose their environmental, social and governance goals in publicly available sustainability reports. Although nine of the ten largest shipping companies address whale strikes as an area of concern in their reports, the degree to which companies take action on this issue varies widely. Also, to our knowledge, none of these sustainability reports explicitly mentions megafauna other than whales.In 2007, the International Whaling Commission launched a long-term initiative to collect and analyse information about reported whale strikes: the Global Ship Strikes Database. With greater engagement from shipping companies, port authorities and industry partners, a centralized database of strikes could be built for all affected species. As well as protecting marine wildlife by helping ships to avoid collisions, such a database could bolster companies’ reputations in an increasingly eco-conscious world, and lessen disruptions to shipping operations.

Hong Kong’s container terminal is one of the largest in the world.Credit: xPACIFICA/Redux/eyevine

Currently, the International Convention for the Safety of Life at Sea (SOLAS), a treaty that ensures ships registered by signatory states comply with minimum safety standards, requires that all ships engaged in international voyages keep an on-board record of navigational activities and incidents relevant to safety. Adding wildlife collisions and near misses to this reporting could enable information to be collected in a comprehensive ship-strikes database. Another measure could require particular ships to have marine megafauna observers on board. (This already happens on vessels conducting seismic surveys, for example, to ensure that the noise from underwater soundings is minimized when whales are nearby.) On the rare occasions on which animals remain lodged on a ship’s bow, strikes could even be recorded by port authorities.
What whale falls can teach us about biodiversity and climate change
Ways to record ship strikes without direct human involvement are being developed, including forward-facing and thermal-imaging cameras, infrared and thermal sensors and underwater echo sounders to image animals. Technology developed by the Woods Hole Oceanographic Institution in Massachusetts uses a camera the size of a shoebox and an artificial-intelligence (AI) algorithm to help ships detect and avoid whales10. (The algorithm is trained to identify whether a whale is present; if so, the program sends a signal to the ship’s operator so they can slow down or change course.) Also, the shipping industry is increasingly using advanced autopilot systems based on AI and deep learning11. In principle, hazard-detection systems on autonomous vessels could be trained to identify marine megafauna, log incidents and implement any necessary evasive manoeuvres.Conventions and treaties that are already in place to increase industry and public engagement in ocean-environment issues could help with all this. But instruments such as the Biodiversity Beyond National Jurisdiction treaty (a framework adopted earlier this year to tackle biodiversity loss on the high seas) must explicitly address the issue of ship strikes. Currently, there is no mention of this in the treaty.Shipping regulationsThe best way to reduce strikes is to separate ships from wildlife. The International Maritime Organization (IMO) is a specialized UN agency responsible for worldwide shipping regulations. Through SOLAS, the IMO can reroute ship traffic to avoid collisions with a floating object or to ensure that areas crucial for some species’ feeding or reproduction at particular times of year are avoided.Permanent or seasonal traffic diversions around wildlife areas have proved hugely effective2. For whales, even minor routing changes in high-risk areas have led to substantial reductions in strikes. For instance, in the Bay of Fundy off Canada, moving a shipping route eastwards by just 4 nautical miles (7.4 km) in 2003 reduced the risk of vessels colliding with North Atlantic right whales by 90%12.

A whale shark (Rhincodon typus) thought to have been scarred in a collision with a vessel.Credit: Claudio Contreras/Nature Picture Library

Several studies and reports show that, in places where ships cannot be rerouted, speed reductions can lower the risk and the lethality of a strike2. In 2008, voluntary and mandatory speed limits of 10 knots (18.5 km per hour) were applied in certain areas along the US east coast. In the first 5 years after implementation, there were no records of ships striking North Atlantic right whales either inside or within 45 nautical miles of these areas13. Studies incorporating emissions show that speed restrictions can bring other benefits. In a 2019 study, decreasing speeds by as little as 10% lowered the risk of ships striking whales by 50%, reduced underwater noise by 40% and cut greenhouse-gas emissions by 13%14.Despite the evidence that rerouting and speed reductions mitigate ‘ocean roadkill’, restrictions on ship routes and speeds remain disparate and uncoordinated, just like data collection on marine animals. A global, IMO-mediated treaty mandating maximum average speeds — and rerouting to ensure ships avoid areas of high collision risk — could be one of the easiest ways to protect wildlife from ship strikes. In fact, regulations introduced this year to ameliorate the effects of climate change from shipping, such as the IMO 2023 Energy Efficiency Existing Ship Index and the Carbon Intensity Indicator, already stipulate lower speeds for certain vessels.A cloud-based, open-data portal could facilitate the establishment of up-to-date, dynamic policies by integrating data on animal and ship movements, risk maps, geo-referenced strike reports, current spatial protections and relevant maritime features into a single mapping resource. This would be similar to HUBOcean, which brings diverse data sources together on one platform to enable scientific collaboration, industry transparency and regulation. Crucially, data could be made available to all stakeholders, from government agencies and non-governmental organizations to academic researchers and industry partners.Monitoring adherenceOnce regulatory changes have been relayed to industry, adherence to speed and route restrictions could be monitored at a national level using data from Automatic Identification Systems. Ship owners, shipping companies and port authorities could also help to ensure regulatory compliance. Financial penalties could be used to discourage speeding or encroachment in no-go zones. In principle, subsidies, tax breaks and other forms of governmental financial support aimed at environmental objectives could be used to reduce ship strikes on marine megafauna.Because governments are unlikely to act without sufficient public pressure, a global ‘wildlife-safe’ shipping eco-certification scheme could be crucial. Similar to NOAA’s ‘dolphin-safe’ tuna-can labels — which aim to signal compliance with US laws and regulations around tuna fishing operations — this would help to increase consumer awareness of the problem and enable informed choices. Scaling up the success of voluntary certification programmes, such as Friend of the Sea’s Whale-Safe label, alongside its certification of seafood from sustainable fisheries and aquaculture, would greatly increase the visibility of this issue.Loss of the ocean’s largest animals will have major unforeseen consequences for the health of the seas. Making ship strikes a higher priority globally is one immediately achievable way to help to conserve the world’s most vulnerable and iconic marine species. More

In a remote national park on Australia’s most southwestern tip, a lone radio tower stands above a quiet wetland. Every five seconds, it collects signals from a few dozen young tortoises hiding out beneath the glassy waters. The tiny tortoises don’t journey far, but researchers are tracking their every move. The fate of a species — one of the most endangered in the world — might depend on these data.There are fewer than 70 adult western swamp tortoises (Pseudemydura umbrina) living in the wild in two small wetland reserves north of Perth, Australia. These spots are all that remains of the creatures’ native habitat, and they are drying out, owing to rising temperatures and a reduction in rainfall. So, in August last year, scientists selected 41 juvenile tortoises from a captive-breeding programme in a zoo and released them into this national park, some 330 kilometres south of where the tortoises are naturally found. The aim is to see whether the animals can tolerate cooler climates, and whether this new habitat might ensure the species’ future as the planet warms.This experiment is part of a series of closely monitored field trials testing one of the most controversial strategies for saving a species — a concept called assisted migration. The tortoise is thought to be the first vertebrate to be moved beyond its historical range because of climate change.Nicki Mitchell, a herpetologist at the University of Western Australia in Perth, is leading the project that is trying to save the tortoise. Her team is now on their fourth trial of releasing captive-bred tortoises into selected wetlands to test the potential of assisted migration, also called assisted colonization. It’s a high-stakes strategy — and one that researchers have long debated. “It is a demonstration project for the world, and we particularly want to make sure there are no perverse outcomes,” Mitchell says.Conservation biologists and land managers have long resisted the idea of assisted migration, mainly because introduced species could become invasive pests, carry diseases or upend existing ecosystems. Few places know the risks better than Australia, which has waged war against cane toads, rabbits and other invasive species that people purposefully introduced to the continent in ill-fated schemes.But attitudes towards assisted migration are slowly shifting as conservationists realise just how fast the climate is changing. Several projects are in the works, only a step or two behind the swamp tortoise experiments. Researchers in eastern Australia are testing plans to move critically endangered pygmy possums, which are threatened by increasing temperatures and droughts, and scientists in Hawaii are relocating seabirds to higher ground, to protect them from rising seas that are fast destroying their nesting habitat.

Hayley Bates hopes to transfer mountain pygmy possums to lowland environments.Credit: Tamara Dean

Those leading the charge are urging their peers to confront difficult decisions head-on, lest more species go extinct. And as a first test, the swamp tortoise trials are in the spotlight as researchers wait to see whether the project proves successful. Early results suggest that the juveniles are growing as expected, but the researchers say it’s still too early to reach a conclusion; in a previous trial, the tortoises failed to thrive in another southern location that had looked good on paper.“What changes perception more than anything,” says Lindsay Young, a conservation biologist working in Hawaii on the seabird project, “is establishing a precedent for having done it successfully.”Nowhere to goFor a species at the forefront of research and conservation, the swamp tortoise is an unassuming creature. No bigger than a human hand, they have dark, plain shells and spend the wetter months in shallow ponds. When those dry out during the heat of summer, the animals settle under bushes and logs, entering a dormant state called aestivation until the rains return.This rare and elusive tortoise was presumed extinct when it was first described from a museum specimen in 1901. Half a century later, in 1953, it was rediscovered in the wild. But the tortoise has nowhere to go. The last fragments of its known wetland habitat on the outskirts of Perth are now fenced in, surrounded by the expanding city and drying out despite efforts to pump water into them. Predators, poachers and wildfires also threaten the tortoises’ existence.
Invasive palms and WWII damaged an island paradise. Could fungi help to restore it?
The strategy of assisted migration is not a new one. It was first proposed in 1985, but it has not seen widespread use. Barely a dozen species of tree, lichen and butterfly have been moved to cooler climes because of foreseen changes to their climatic niche. Many more have been shifted to avoid predators, pathogens or human construction — which are more immediate, localized threats than climate change.Shifting a species within its known range or restocking wild populations with captive-bred animals is common practice in conservation. But assisted migration oversteps ecological boundaries and makes many conservation scientists feel uneasy. “It’s an enormous thing for conservation to do, to change the range of a species to keep it alive,” says Kylie Soanes, a conservation biologist at the University of Melbourne, Australia.Nevertheless, Mitchell sees trialling assisted colonization as a better alternative to watching the last remaining captive populations of an iconic species dwindle to extinction.Mitchell hatched the idea to shift the tortoise south with Gerald Kuchling, a herpetologist at the Western Australian government’s Department of Biodiversity, Conservation and Attractions, and principal scientist of the department’s swamp tortoise recovery team. Given the tortoises’ rarity, the researchers had to devise methods of predicting where suitable wetlands for the tortoise were likely to occur two decades from now, on the basis of wetland hydrology, local climate projections and the tortoises’ physiology1. That modelling, which screened more than 13,000 locations, led the researchers to one spot: an area in the southwest corner of Western Australia with plenty of seasonal wetlands, two of which would become the site of the first assisted colonization trial in 2016.The team released a dozen captive-bred tortoises at each southern site as part of the trial and, at first, it looked like a good move. The introduced tortoises, which had small radio transmitters glued to their shells, grew as well as their northern kin2. In 2021 a bushfire destroyed 90% of the tortoises’ original habitat. But then data started trickling in from the next trial, which involved releasing another 48 radio-tagged juveniles in 2018.The results, published in May3, suggest that the tortoises released in the southernmost wetland basked less and grew more slowly than did those in their home haunt. The wetland, the researchers discovered, was fed by a chilly stream and it rained there more often than it did in the creatures’ home habitat. That meant that the introduced tortoises were less active; which might have impeded their growth.

The western swamp tortoise is Australia’s rarest reptile.Credit: Matthew Abbott/New York Times/Redux/eyevine

Despite those results, Mitchell says the 2018 trial still yielded important insights about how swamp tortoises spend their days, thanks to custom-made data-loggers glued to their shells that gauged when the animals were basking in the shallows and when they were submerged deep underwater. “None of that was known because they’re an incredibly cryptic species,” she says. “You very rarely observe them in the wild.”Past and current trials have been approved on the proviso that the team can monitor the tortoises closely, recapture them and return them to Perth Zoo. “Which is why we’re aiming to find every animal we can, as often as we can,” says Mitchell, whose team did recapture the tortoises that were released in the first few trials. The tortoises are unlikely to become invasive or encroach on other threatened species, she adds, because they grow so slowly and eat only small aquatic insects and tadpoles.But monitoring is arduous and expensive, and the cost of the field work is draining the researchers’ remaining funding. Mitchell and her team of graduate students and volunteers are continuing their data collection until at least the end of 2023 with financial support from World Wildlife Fund Australia.Despite her hopes for the project, Mitchell says that assisted colonization won’t be suitable or feasible for every species at risk. “There are millions of species,” she says, “and we’re not going to get to many of them.”Climate concernsSean Williamson is one conservation biologist eager to see how the programme delivers. Based at Monash University in Melbourne, he’s been watching its progress from afar. He says Mitchell’s research has kindled cautious interest among conservation biologists about whether assisted migration could work for other egg-laying reptiles, such as green sea turtles (Chelonia mydas), which nest on low-lying islands throughout the tropics.
Expeditions in post-war Colombia have found hundreds of new species. But rich ecosystems are now under threat
Williamson, like all of the researchers Nature spoke to, is wary of the risks that assisted migration poses. But, when faced with losing an “unfathomable” number of species to climate change, he says conservation biologists should consider every tool at their disposal, including assisted migration.Researchers are exploring this option with a population of mountain pygmy possums (Burramys parvus). In the wild, these palm-sized possums are marooned in the highest reaches of the Australian Alps, in a fragmented area totalling less than 7 square kilometres. The possums survive winter by hibernating under a blanket of snow. But with less snow and fewer moths to eat in drought years, the possums are living on the edge in their current habitat.Yet, fossil evidence suggests that their ancestors lived in lowland rainforests 25 million years ago4. So researchers built a facility near Lithgow, Australia — some 500 km from where the animals are usually found — to test whether modern possums could survive in the same environment as their forebears.Hayley Bates, a biologist at the University of New South Wales in Sydney, Australia, and her colleagues moved 14 possums in 2022 from another facility to open-air enclosures with artificial rock walls and nesting boxes that mimic the animal’s home boulder fields. “So far, they’re doing pretty well,” she says.The possums have started breeding, which suggests they can adapt to lower elevations with occasional snow. Bates says seeing the possums breed is an important milestone in the project, which is built on a decade of field work to understand the species. The long-term plan is to release the possums into a series of small, fenced enclosures in the bounds of the wildlife sanctuary where the breeding facility is built.Any potential releases into outdoor fenced sites are still another 5 to 10 years away, and hinge on many more experiments with captive-bred possums, to work out what they might eat in their new home, and how they fare with unfamiliar predators.Meanwhile, in Hawaii, Young and her team at the non-profit organization Pacific Rim Conservation based in Honolulu, where she is the executive director, are working to save seabird species that aren’t yet critically endangered, but nest on the edge of low-lying islands. Rising seas and storm surges are already wiping out countless nests, Young says, and hurricanes have erased some of Hawaii’s northwestern atolls. These threats will only intensify as the planet warms.

Conservation biologist Lindsay Young collects a black-footed albatross.Credit: Eric VanderWerf/Pacific Rim Conservation

Pacific Rim Conservation is working to make sure enough black-footed albatross (Phoebastria nigripes) chicks survive to sustain future populations. In 2017, the team began relocating weeks-old chicks from Hawaii’s northwestern atolls to Oahu, an island on which black-foots don’t usually nest.Operating under state and federal permits, Young and her colleagues housed each chick in its own A-frame shelter at the new nesting ground, a state park, some 225 km from their usual breeding spot, and hand-fed them fish milkshakes until they fledged5.It will be a few years yet before the relocated black-foots reach maturity and possibly begin breeding at their new nesting site, alongside other seabird species. Being long-lived birds that feed at sea, the albatrosses aren’t expected to become invasive or impinge on other land-dwelling species, Young says.Unpredictable risksFor a long time, some conservation scientists said that assisted colonization wasn’t an idea their peers should even be discussing. However, a survey conducted from 2016 to 2021 in Hawaii suggests that attitudes are changing, particularly among wildlife managers who realise their past inaction and their unwillingness to accept risk might have led to some extinctions. This is especially palpable on small island nations where species are hemmed in by rising seas.
Protecting monarch butterflies’ winter home could mean moving hundreds of trees
“We’re just on the front lines here,” says Melissa Price, a wildlife ecologist at the University of Hawaii in Manoa, who conducted the survey6 of 22 conservation practitioners. Scientists who are normally cautious are now considering making bold moves to save some Hawaiian species from disappearing, which “tells me how dire the situation is”, she says.Some researchers who once opposed assisted migration are reconsidering their stance. Mark Schwartz, a conservation scientist at the University of California, Davis, says he has become more accepting of assisted colonization now that he has seen researchers working methodically to assess the risks of moving species, such as with the western swamp tortoise.“But that doesn’t mean that I don’t deeply worry about our capacity to do it right,” Schwartz says. That’s why he and other researchers are calling for the establishment of global standards on assisted colonization to guide its responsible implementation7.Other researchers and organizations are ambivalent. In a statement outlining its position to Nature, the Ecological Society of Australia says that moving species into new habitats is expensive and risky, making assisted colonization a ‘last resort’ option in conservation planning. But the society acknowledges that as climate change worsens, “we may have to turn to assisted migration more often”. It also says that cutting greenhouse-gas emissions and halting habitat loss are the two best ways to safeguard against extinctions.Ali Chauvenet, an ecological modeller at Griffith University in Brisbane, Australia, says that there are many tools available to help in making decisions about assisted migration. These include modelling techniques to estimate the possible impact on ecosystems and risk-assessment frameworks to judge the likelihood that an introduced species will become invasive, or survive in a new place.

Black-footed albatross chicks were moved to Oahu, Hawaii, to establish a nesting colony there.Credit: Lindsay Young/Pacific Rim Conservation

Invasive-species biologists tend to oppose the idea because of what could go wrong. One study tried to compute the consequences of assisted migration and the likelihood of its success8. In a model simulation, it found that there is a good chance of saving selected species with assisted migration, but a recipient ecosystem might lose nearly half of its species on a rare occasion. However, the model simulated assisted migration in an artificial ecosystem of just 15 species. “It’s very hard to predict what’s going to happen,” Chauvenet says.Despite some researchers warming to the idea of assisted colonization, there are major regulatory hurdles to moving species into new areas, says Lesley Hughes, an ecologist at Macquarie University in Sydney. Government agencies, at least in Australia, rarely recognize assisted migration — or any interventionist action — as a valid option in threatened species recovery plans, according to a review9 of 100 plans that Hughes conducted in 2018. Since then, there has been some progress, she says, “but it’s at a glacial pace”.In the past few years, the US National Park Service and Parks Canada have both enlisted the help of researchers to develop frameworks and evidence maps10 on assisted migration. And in June last year, the US Fish and Wildlife Service announced proposed changes to the US Endangered Species Act that would make it easier for conservationists and wildlife officials to consider assisted migration as a conservation tactic, say researchers.However, the thought of moving species across ecosystem boundaries raises questions about who gets to make those decisions and draw those lines. Indigenous people, for example, have long been excluded from conservation circles, says Jacqueline Beggs, an invasive-species biologist at the University of Auckland, New Zealand, who is of Ngāti Awa descent.“There’s going to be a lot of deep conversations required,” Beggs says, “to think our way through the issues, particularly from an Indigenous perspective.”A colder homeThe swamp tortoises’ wintertime wetlands are, for now, brimming with water. But come December or early January, they will dry out, at which point the tortoises will hunker down and aestivate. Before then, Mitchell and her team will ramp up their monthly monitoring to fortnightly welfare checks — to save any radio transmitters from falling off during the juveniles’ growth spurt. But there’s nothing to stop the tortoises from getting picked off by predators or waddling out of range.The animals could get some help from the authorities. In October, Australia’s Commonwealth government added the swamp tortoise to a priority list of the top 110 threatened species and included moving the tortoise to southern climate refugia as an action item. Mitchell hopes the federal government will supply funding for the project; then her team could hand over the reins to a locally based team that could monitor the tortoises’ movements, growth and survival.To keep costs down, Mitchell’s team are exploring other monitoring approaches besides radio tracking, such as measuring traces of DNA the tortoises leave behind and tracking the sounds they make using underwater hydrophones.One big question for the future is how well the tortoises can reproduce in colder climates. Mitchell says it could be another 10–15 years before any of the juveniles released last year reach breeding age — if they survive in their new home that long. For the shy, slow-growing swamp tortoise, there simply aren’t any quick answers to these burning questions. More

Europe’s fisheries are catching yellowfin tuna at unsustainable levels, scientists say.Credit: Marty Melville/AFP/Getty

It is a heart-breaking litany. As the world warms, its oceans are acidifying — they have become 30% more acidic during the industrial era. The area covered by low-oxygen marine ‘dead zones’, which are almost devoid of life, has more than quadrupled1 since 1960. By 2025, the amount of plastic in the seas is expected to total 150 million tonnes2. Even now, only 3% of the ocean is strongly protected by marine reserves.None of the 17 United Nations Sustainable Development Goals (SDGs) is on track to be achieved by 2030, as Nature has been reporting in this series of editorials. But progress on a few, including the 14th goal — to conserve and sustainably use the oceans — has actually been going backwards since the 2015 UN summit at which the SDGs were agreed.SDG 14 comprises ten targets and pledges intended to address acidification, pollution, overfishing, biodiversity loss and other ocean ills. Three are on track, and two others are progressing, albeit too slowly to be achieved by the deadline. The remaining five have either stagnated or regressed. This failure is not for want of talking or pledging. In 2020, under the auspices of a High Level Panel for a Sustainable Ocean Economy (the Ocean Panel), co-chaired by Norway and Palau, 14 coastal states committed to 100% sustainable management of their waters by 2025. By the end of 2022, 17 countries, accounting for more than 40% of the world’s coastal zones, were covered by this pact.
UN high seas treaty is a landmark – but science needs to fill the gap
In February 2022, meanwhile, France hosted representatives of more than 100 countries at a historic ocean summit in Brest. A number of attendees vowed to join a plan to protect 30% of the ocean by 2030, to adopt new laws to safeguard marine life in waters beyond national ownership, and to end illegal, unreported and unregulated fishing, a term that covers a gamut of unsustainable practices that cost the global economy up to US$50 billion a year.It’s not a lack of knowledge that’s stopping words being translated into actions. In 2018, the Ocean Panel commissioned a two-year review of available intelligence on ocean threats and opportunities, from some 250 experts around the world, closing many existing gaps. That’s not to say there isn’t room for improvement — there’s a need for better regional data on fish biomass, for instance, which could help efforts to determine where and how to protect stocks.But the one gap science alone cannot fill is a lack of leadership, something that is most evident in the disturbing misalignment of promises and action from self-proclaimed ocean champions. In June, Norway announced new permits for offshore oil and gas drilling worth $18.5 billion, and proposed opening some 280,000 square kilometres of its waters to deep-sea mining, a nascent industry that risks wreaking havoc on poorly understood ocean ecosystems. Similarly, France, also the host nation for an upcoming UN Ocean Conference in 2025, is opposing a measure to exclude a destructive fishing practice called bottom trawling from marine protected areas in the European Union.The EU itself seems to be operating two sets of policies. Successes it has chosen to highlight include a 37% decrease in fishing pressure — a measure of the extent to which a stock is being exploited — and a 22% increase in fish biomass in its waters between 2005 and 2020. This contrasts sharply with its actions elsewhere; it has been fighting conservation measures in the Indian Ocean that would curb chronic overfishing of yellowfin tuna. French and Spanish ships harvest up to one-third of tuna in these waters with the aid of fish-aggregating devices — large floating structures made of wood or plastic that attract fish, including juveniles, and are associated with unsustainable fisheries.
Protecting the ocean requires better progress metrics
Other big maritime nations — China, India, Brazil and Russia — are facing major challenges in achieving SDG 14. But none has held itself up as an ocean leader. Conversely, Chile’s government is making strides. It has designated 41% of the country’s waters for protection, and, last year, the government proposed (albeit unsuccessfully) to revise the constitution, in part to bring in broader ocean-management measures, including more stringent controls on coastal salmon farming.There’s still time to turn the ship around. Key to this will be the implementation of measures to hold nations accountable for their promises, for which Nature and others have previously advocated. This, in turn, needs better progress metrics. In this respect, researchers can and are playing a crucial part3. There’s also a need to finance help where it’s needed. According to one analysis, implementation of SDG 14 will require an extra $150 billion a year4. But implementing some SDGs will make funding available for others. Ending harmful fisheries subsidies, for example, should free up between $22 billion and $35.4 billion a year5.Much of the extra funding required for SDG 14 has already been negotiated through other forums, such as the UN’s Green Climate Fund. And last December, as part of the Kunming–Montreal Global Biodiversity Framework, nations agreed to raise at least $200 billion a year by 2030 from public and private sources to fund biodiversity protection, both on land and in the water.This isn’t just about dewy-eyed sentiment for our beautiful blue planet: the livelihoods of hundreds of millions of people depend on the oceans and the life they sustain. There’s much that scientists can do to achieve ocean sustainability. But to get SDG 14 back on track for 2030, world leaders must stand by the promises in their rhetoric. More

Freshwater biodiversity in China’s upper Yellow River is once again under threat, this time from the planned Heishan Gorge hydraulic engineering project. This follows the construction of multiple reservoirs along the Yellow River basin since the 1950s. Local governments should learn from the past and assess the project’s potential ecological impacts before going ahead.
Competing Interests
The author declares no competing interests. More

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A growing agricultural sector is one of the greatest global threats to wildlife. But an analysis shows that in Costa Rica, diversified farms — which host a variety of crops, as well as plants that emulate natural habitats — could help to stem the loss of some forest birds1.

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doi: https://doi.org/10.1038/d41586-023-02748-6

References

Subjects

Conservation biology More