Goal to “halt and reverse” biodiversity loss by 2030 – a headline aim of the COP15 biodiversity summit – could take 80 rather than eight years to achieve, say conservationists
5 December 2022
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 draft agreements 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 David Obura 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 a study 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. “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 aims 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. Tom Oliver 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.
Mark Burgman 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.
E.J. Milner-Gulland 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.”
Journal reference: One Earth, DOI: 10.1016/j.oneear.2022.11.013
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