Large-scale monoculture plantations have devastated tropical forests worldwide, but a recent study finds that creating islands of native trees can be a way to restore biodiversity on degraded lands.

The Indonesian island of Sumatra is one of the most biodiverse regions in the world. However, the demand for palm oil has led to rapid deforestation for monoculture plantations, leading to a tremendous loss of biodiversity.  In the recent study, an international team of researchers wanted to see if creating tree islands, or strategically planting patches of just a few native species within degraded or agricultural lands, can help restore native woody plant diversity.

Researchers cleared 40% of the existing oil palm trees for each of their 52 experimental plots. They then planted between zero and six native tree species on each of their tree islands. They also kept four control plots with oil palms standing. The tree islands vary in area from 25-1,600 square meters (269-17,222 square feet).

Six years after their establishment, the researchers found that the tree islands were home to an additional 2,788 woody plants of 58 different species from 28 families. While most of the plants typically thrive in open habitats, including secondary forests that regrow after a disturbance like agriculture, one-third of the species were associated with tropical forests. Roughly 20% of the plants were endemic and 10% were non-native. The diversity of trees in the islands was also higher than in the rest of the oil palm plantation but still far lower than in undisturbed forest, highlighting the critical conservation value of standing forests.

Furthermore, large tree islands, greater than 400 m2 (4,300 ft2), hosted 94% of the native tree species found in the study and all of the endemic species. In contrast, small tree islands hosted just 45% of native species and a quarter of the endemic species.

Previously, the researchers had found that the tree islands had greater diversity of several groups of animals, including birds and bats. Large tree islands likely provide better habitat for such animal seed dispersers, the authors write. Geographically large tree islands can also create a more stable microclimate, while more leaf litter improves soil conditions; both make it easier for new trees to get established.

In the previous study, the researchers found that tree islands didn’t reduce yields of oil palm. Palms near tree islands actually had improved yields, which made up for trees that were removed.

“This is a landmark study,” Robin Chazdon, a tropical ecologist with the University of Connecticut, U.S., who wasn’t involved in the study, told Mongabay by email.

“The outcome is a hopeful message that it is possible to provide islands of hope for native vegetation within landscapes dominated by large-scale oil palm plantations,” she added.

Banner image: Habitat loss for oil palm is driving orangutans toward extinction. Image by Marc Veraart via Flickr (CC BY-ND 2.0).

For decades, the slender-billed curlew, a grayish-brown migratory wetland bird with a long, arched bill, has evaded detection, prompting speculation about whether the species is still out there. Now, a new study has confirmed that the species is indeed most likely extinct.

“Speaking personally it’s a source of deep sadness,” Geoff Hilton, conservation scientist at U.K.-based charity Wildfowl & Wetlands Trust, who wasn’t involved in the study, told Mongabay by email. “I spent several years working on ways to bring this species back from the brink … I’m gutted!”

While details of the slender-billed curlew’s (Numenius tenuirostris) exact population size and breeding sites have remained hazy, the species is known to have historically bred in Central Asia and migrated to Europe and North Africa. However, the bird has likely been scarce since the mid-20^th century, said Graeme Buchanan, study lead author and conservation scientist with U.K-based NGO Royal Society for the Protection of Birds (RSPB).

The species was last photographed in 1995 at Merga Zerga on Morocco’s Atlantic coast. Since then, experts have speculated the bird was extinct, although the IUCN Red List still classifies it as critically endangered, based on a 2018 assessment

There was a need for a formal, quantitative assessment of the species’ status to prevent withdrawing conservation support too soon or too late, Buchanan told Mongabay.

So, following the IUCN’s framework, Buchanan and his colleagues reviewed all known sightings of the species maintained by the RSPB in a database, estimated impacts of various threats to the bird, and examined past surveys. They concluded there’s a roughly 96% probability the species is now extinct, and that it likely happened in the mid-1990s.

“I agree with the authors’ approach and so unfortunately I must agree with their conclusions,” Hilton said. “Of course, the authors do not say that the species is definitely extinct, just that it is extremely likely to be extinct.”

This is a wake-up call the conservation sector “probably didn’t need,” Hilton added. “We arguably spent too much time watching the bird’s decline and not enough actually trying to fix things,” he said. “Although that’s easy to say: it’s not clear what really we could have done that would have made a difference.”

A recent IUCN update notes that various other migratory shorebirds are now more threatened with extinction than before.

As for the slender-billed curlew, the study’s authors recommend updating the species’ IUCN status to extinct. Still, they hold out a slim hope someone might spot one of the birds again.

“If someone spots it now, get a photographic evidence,” Buchanan said. “It’s very important to have no uncertainty as to whether or not this is the species. Second, call us. We’d be delighted to be proven wrong and we could try to reinitiate conservation efforts.”

Banner image of a slender-billed curlew illustration by Elizabeth Gould & Edward Lear via Wikimedia Commons (Public domain).

Certain minerals and elements, including cobalt, copper, lithium and nickel, are crucial for the manufacture of renewable energy technologies, including electric vehicles and solar panels. However, the extraction and processing of those minerals often takes place in developing countries, far from public scrutiny and without consent from local communities, which can be left with the burden of pollution but little economic benefit.

Key stakeholders at the ongoing U.N. climate meeting, COP29, are pushing for greater transparency, arguing for the need to ensure local environments are protected and economies improved along the critical minerals supply chain.

Efforts for a binding global treaty on traceability for critical minerals was first launched by the Colombian government on the sidelines of the recent U.N. Biodiversity Conference in Cali, Colombia. The goal is to ensure a global pact is ready to be signed by November 2025 when the next U.N. climate talks meet in Belém, Brazil.

“We see a rush for resources, with communities exploited, rights trampled, and environments trashed. Too often, we see the mistakes of the past repeated in a stampede of greed that crushes the poor,” said U.N. Secretary-General António Guterres while calling for the world to enact stricter rules for those involved in the value chain for critical minerals.

“The aim is to empower communities, create accountability and ensure that clean energy drives equitable and resilient growth. That includes advancing efforts to ensure maximum value is added in resource-rich developing countries,” Guterres added.

At the 2023 U.N. climate meeting, the global community set a goal to triple the world’s renewable energy capacity by 2030. Such an increase in renewable energy is needed to fight the climate crisis but would likely result in a commensurate increase in demand for critical minerals as well. That makes efforts to ensure greater transparency in the value chain more important than ever for local communities and Indigenous people living in resource-rich areas.

“This is a time when cooperation is paramount for nations to effectively address multiple crises,” said South African Nozipho Joyce Mxakato-Diseko, who co-chairs the U.N. panel on critical energy transition minerals.

The principles underpinning the U.N.-backed initiative include advancing fairness, justice, equity and human rights across the critical minerals value chains. It seeks to source critical minerals in a way that protects the environment and ensures prosperity in resource-rich developing countries.

“We must now seize the opportunity to grow our economies, protect our societies, preserve our environment and share benefits more justly while we tackle the climate crisis,” said Ditte Juul Jørgensen of the European Commission and co-chair of the Panel on Critical Energy Transition Minerals­­­­­. “Only in this way, will we tap the potential of the energy transition and create new and shared benefits for all,” she added.

Banner image: A cobalt mine in Central Africa. Image by Fairphone via Flickr (CC BY-NC 2.0).

Negotiators at the ongoing U.N. climate talks in Baku, Azerbaijan, have adopted a controversial provision on carbon trading that critics say will enable rich countries and companies to simply pay to continue emitting.

The adoption of Article 6 from the Paris Agreement will outline ways that countries and companies can trade emissions on a carbon market, which the World Bank Group, responsible for delivering climate finance to developing countries, calls a “game changer.” The U.N. Trade and Development agency similarly describes the carbon market as a “powerful tool.”

However, many civil society organizations are strongly opposed to carbon markets, citing concerns that communities in areas where carbon credits are generated to “offset” the carbon emitted elsewhere are often not consulted on carbon projects and rarely benefit.

“We don’t want carbon credits at all because they do not help the community or the women of Asia Pacific,” Ranjana Giri, a young climate advocate from Nepal, told Mongabay at the Baku summit, COP29. Giri represents the Asia Pacific Forum on Women, Law and Development, a leading network of feminist organizations and individual activists in the Asia-Pacific region.

Giri said carbon markets don’t benefit women or local communities because the profits mainly go to agribusiness companies and their executives.

Carolina Mutari, a youth activist from Kenya, also slammed the concept.

“I totally disagree with carbon markets. They are false solutions right from the start,” Mutari, attending COP29 as a representative of a group of young people from across Africa, told Mongabay.

“The reason I oppose them is that the Global North is shifting the responsibility of climate mitigation onto the most affected communities in the Global South. Essentially, this lacks any form of climate justice and undermines the principles of climate justice — such as the right to development and equity.”

A metric ton of carbon may cost $3 to $10 in the African market, and can sell for $100 to $200 in Europe.

Financing the fight against climate change has long been a sticking point at the annual U.N. climate meetings, and is a special focus at the current COP. The adoption of Article 6 was one of the top priorities of the meeting, though many parties said they felt the process was rushed. Nonetheless, it’s emerged as one of the most critical outcomes of COP29 so far and will help clear the way for carbon trading to begin in earnest.

COP29 lead negotiator Yalchin Rafiyev, who is also Azerbaijan’s deputy foreign minister, hailed the development as “a game-changing tool to direct resources to the developing world and help us save up to 250 billion dollars a year when implementing our climate plans.”

Giri disagreed, saying, “We feel very disappointed, very sad, and we believe our future is in danger.”

Banner image: Ranjana Giri and fellow youth climate activists at COP29, courtesy of  Liani MK.

The last wild Round Island hurricane palm, a rare tree native to Mauritius, snapped during a windstorm in mid-September, marking its extinction.  Once thriving on a tiny island in the Indian Ocean, the tree had stood alone for decades as the only survivor of its kind.

Standing 9 meters (30 feet) tall, the Dictyosperma album var. conjugatum hurricane palm was known for its pale blue-tinted fronds and dense crown, and described as “breathtaking” by rare-palm enthusiasts.

“The tree was like the Eiffel Tower of Round Island. Anybody working on plants, reptiles, seabirds, or invertebrates would say, ‘We’ve got to go see it,’” Vikash Tatayah, conservation director of the Mauritian Wildlife Foundation, told Mongabay by phone.

It was native to the 1.7-square-kilometer (0.7-square-mile) Round Island, a strategic conservation area for Mauritius due to its high number of rare, endemic species, including reptiles and birds.

The foundation has been working to save the teetering tree, and other species, for decades in partnership with the Mauritian government and the U.K.-based Durrell Wildlife Conservation Trust. But years of decline ultimately took their toll.

The trees’ decline began in the 19th century when British colonizers brought in animals like rabbits and goats. The invasive species overran the island’s ecosystem, eroding the topsoil that helps hold palm trees in place. By 1994, only two trees were left; one fell during a cyclone later that year.

“It’s almost like losing something forever. It’s really profound,” Malin Rivers, head of conservation prioritization at U.K.-based Botanic Gardens Conservation International (BGCI), told Mongabay by phone.

According to the IUCN Red List’s first Global Tree Assessment, carried out by BGCI and published recently, 46,337 of all tree species, 38% of the global total, are at risk of extinction.

Islands have the highest number of threatened tree species worldwide, the assessment found, and climate change is adding to threats, particularly in tropical regions, with island trees facing rising sea levels and stronger, more frequent storms.

“Trees fulfil so many different functions. On an ecosystem service level, they will provide us with water security, prevent erosion and absorb carbon,” said Rivers, who coordinated the assessment. “But they also define the ecosystems and the habitats where they grow, which trickles down to other species.”

The Round Island hurricane palm supported specialized insects and geckos. “The cascading effects of its extinction are as concerning as the loss of the tree itself,” Tatayah said.

Despite the loss, he said he hopes that in 30 years’ time, researchers can reintroduce the variety to Round Island with “careful genetic work.”

“It’s discouraging, but there is a glimmer of hope,” Tatayah said.

Banner image: This Round Island hurricane palm (Dictyosperma album var. conjugatum), photographed in 2021 while it was still healthy, was the last of its variety left in the wild. Image courtesy of Vikash Tatayah.

Emissions of methane, a greenhouse gas several times more potent than carbon dioxide, increased at record-high rates between 2020 and 2022. A new study suggests that rather than fossil fuels, microbes were responsible for this recent methane surge.

Until the early 2000s, fossil fuel production drove much of the increase in atmospheric methane, study lead author Sylvia Michel, senior scientist at the University of Colorado Boulder, U.S., told Mongabay by email. Fossil fuels “are still a very large part of the methane budget,” she said. “They just aren’t the cause of the recent increase.”

After a short pause in growth from 1999 to 2006, atmospheric methane concentrations have risen rapidly. Between 2008 and 2014, methane concentrations increased by around 5 parts per billion (ppb) per year, then by 9 ppb per year between 2014 and 2020. From 2020-2022, though, methane went up by around 15 ppb per year.

To find out where that latest surge came from, the study’s researchers analyzed methane in air samples collected from 22 sites globally. They ran the samples through a specialized spectrometer, and used a simple computer model to simulate and track the likely source of the emissions. In the end, the study found microbial sources have been driving increases in methane emissions since 2006, with their contribution especially high since 2020.

“We were surprised by how much the 2020-2022 methane increase could be attributed to microbial sources,” Michel said. These sources include single-celled Archaea, microorganisms that live in oxygen-free environments like wetlands, the guts of cows, rice fields, landfills or waste facilities, she added.

Michel, however, cautioned they can’t differentiate if the recent methane emissions are from natural sources like wetlands or human sources like landfills.

Naveen Chandra from the Research Institute for Global Change in Japan, who was not involved in the research, told Mongabay by email that the study’s findings “align broadly well with what we already know about how microbial processes respond to changes in temperature and rainfall.” Chandra also studies methane emissions.

“It’s widely recognized that microbial sources, such as wetlands and waste sites, release more methane (CH₄) as temperatures rise,” Chandra said. “These sources account for about half of the global methane emissions, so shifts in climate — like higher temperatures or more rainfall — can have a major impact on the amount of methane entering the atmosphere.”

However, what stood out to him was “the study’s estimate that microbial sources may contribute as much as 90% to recent methane growth.” 

“This is a surprisingly high number,” he said, adding that it might change if more complex atmospheric processes were included in the modeling.

“If this large contribution proves accurate, it’s a concerning signal,” Chandra said. “With rising global temperatures, we could see an even greater increase in atmospheric methane levels in the future, which would have serious implications for climate change.”

Banner image of a wetland in South Africa, by Rhett A. Butler/Mongabay.