Negotiators at the COP15 biodiversity summit in Montreal, Canada, are at risk of setting the world “unrealistic” targets that threaten to undermine global conservation action, researchers have warned.

This week in Montreal, negotiators from most of the world’s countries are gathering to thrash out a global plan to save nature. The central aim of the conference is to agree a new suite of targets that will “halt and reverse” biodiversity loss by 2030 and have humans living “in harmony” with nature by 2050, according to published in June 2022.

But even the most ambitious modelling suggests that the earliest date possible to halt and reverse biodiversity loss is by 2050, says at Coastal Oceans Research and Development in the Indian Ocean (CORDIO), a non-profit organisation in Mombasa, Kenya. “Even that’s based on the most simplistic assumptions, it doesn’t even accommodate climate change,” he says.

Global biodiversity has been declining at an alarming rate for decades. In October, conservation organisation WWF warned that studied populations of mammals, birds, amphibians, reptiles and fish have seen an average decline of 69 per cent since 1970.

Now, in an article on what it will take to achieve a turnaround, Obura and his colleagues say reversing these declines cannot be achieved in just eight years, in part because it can take decades for plant and animal populations to grow to maturity. The goals have “unrealistic expectations and time frames of biodiversity recovery”, write the team.

“It sounds great, we want to do it… but I think the inertia in the system is such that it is just not possible,” says Obura.

“It takes time for organisms to grow, especially large-bodied ones like trees or large herbivores that have a big impact on system dynamics,” he says. “It can take 100 years or more for an ecosystem to really go through successional stages that matter, to get to an end point that counts for what we want.”

Obura says the headline aim of COP15 should be to “bend the curve” of biodiversity loss as fast as possible without setting rigid deadlines for success. Reaching an end state where humans are living in harmony with nature is likely to take at least 80 years, he says.

His wariness over the headline 2030 and 2050 goals is shared by other conservation experts. at the University of Reading, UK, says “full recovery [of nature] is not possible within just a couple of decades”.

“It may be splitting hairs, but new targets can more correctly talk about habitats on the ‘road to recovery’ rather than fully recovered by 2050,” he says.

at Imperial College London also says the 2030 and 2050 targets are “very unlikely to be met”.

Setting unachievable aims risks a repeat of the failure of the Aichi Targets, the study says. The Aichi Targets were a set of 20 biodiversity goals agreed in 2010, but which the world failed to deliver. Obura is concerned that another collective failure to tackle biodiversity loss would undermine global confidence that change is possible.

The “over-reach in ambition may undermine both immediate and long-term actions and commitments needed to achieve success in more realistic time frames”, the study says.

But some conservationists say ambitious targets are necessary to communicate the urgency and scale of action needed.

at the University of Oxford says the 2030 goal is “very ambitious”, but delaying that deadline “just risks governments kicking the can down the road in terms of the fundamental systemic change we need”.

“The 2030 target is what we actually need in order to ensure that our natural capital begins to be restored to safe levels for people and the planet,” she says. “Even if we can’t make it, we need to start to put serious effort into trying, and I don’t believe that a delayed target will provide the urgency that we need.”

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On 7 December, representatives from nearly every country in the world will gather in Montreal for the United Nations’ COP15 summit to tackle the world’s biodiversity crisis. Delays to the meeting have tempered expectations for the outcome of the summit, but participants are holding out hope that the meeting could be as consequential for stemming biodiversity loss as the landmark 2015 Paris Agreement was for action on climate change.

COP15 is the 15th Conference of the Parties to the UN Convention on Biological Diversity, a treaty drafted in 1992 to protect the world’s biodiversity. Parties to the treaty include the European Union and every country in the world except the US and Vatican City, though both will participate in the summit. Representatives from countries meeting in Montreal will negotiate an agreement to shape the next decade of action on biodiversity.

There are 22 targets in the , known as the Global Biodiversity Framework. The draft was a created by a UN working group in the years leading up to COP15 to replace a previous agreement from the last major biodiversity summit held in Aichi Prefecture, Japan, in 2010.

One of the key targets in the draft is a commitment to protect at least 30 per cent of land and water around the globe by 2030. More than 100 countries have joined a coalition in support of this “30 by 30” goal.

That would be a significant increase – as of 2020, 15 per cent of land and about 7.5 per cent of the ocean was protected – but “30 per cent is not enough,” says at Resolve, a US environmental consultancy. Dinerstein is part of a group advocating for 50 per cent of the planet to be protected by 2030.

Other draft targets include offsetting billions of tonnes of carbon dioxide emissions with nature-based approaches such as conserving biodiversity-rich rainforests, stopping the spread of invasive species and reducing pollution from pesticides, fertiliser and waste. Another seeks to end or reduce subsidies for industries that contribute to biodiversity loss, for instance through deforestation.

Climate change will also be a central topic in Montreal. Not only does warming threaten many species of animals and plants, biodiverse forests and healthy ecosystems sequester carbon – and stemming their losses is key to reaching the most ambitious targets of the Paris Agreement. “We absolutely have to conserve the world’s most biodiverse forests if we are going to stay within 1.5°C [of warming],” says Dinerstein.

COP15 was originally set to happen in Kunming, China, in October of 2020, but was pushed back four times due to covid-19. The meeting was moved to Canada to avoid further delays, with China retaining the presidency. The first phase of the convention was held in Kunming in October of 2021. Ministers from more than 100 countries pledged to reach an agreement on the Global Biodiversity Framework in 2022, but stopped short of committing to specific targets.

The delays haven’t helped momentum towards an agreement, says at the Center for Biological Diversity, a US conservation advocacy group. “There’s still way too many brackets” indicating portions of the agreement that are to be determined, says at the Wildlife Conservation Society, a nonprofit organisation in New York.

The working group has a final session just before the convention to try to work out as much as possible, but a packed agenda will start already behind schedule. at the University of Hong Kong says just two of the targets and around 20 per cent of the text in the framework has been agreed to. “A lot of us are very anxious because we haven’t had the degree of progress needed,” she says.

Major sticking points include the role of donor countries and organisations in financing conservation initiatives in lower-income countries – the draft agreement estimates $700 billion would be needed to implement the targets. COP15 will also feature negotiations on the controversial question of who should benefit from medical or other biotechnology based on genetic sequences stored as digital information, as well as discussions on biosafety and the role of synthetic biology in conservation.

If an agreement on the framework is reached at the summit, it would replace the 2010 Aichi targets. Despite partial progress on a few of those targets, such as the amount of protected water and land, none were fully achieved by 2020.

But there is reason to hope any targets agreed to in Montreal will be more successful. For one, there’s more knowledge about how the world’s biodiversity is distributed and how to protect it, says Dinerstein. There is also a greater recognition and involvement of Indigenous people in the process. Indigenous lands often than lands not managed by Indigenous peoples.

“We’ve learned a lot of lessons from nature over the last few years,” ��says at The Nature Conservancy, a conservation non-profit. “I’m hopeful negotiators will come ready to act.”

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