Extinction and optimism
16th September 2020
This piece has been written by Dr Stuart Butchart, Chief Scientist at BirdLife International
The last few days have seen a minor storm of important papers, reports and communications on biodiversity conservation. These have provided plenty of reasons for feeling depressed and despondent.
The 2020 Living Planet Report released last week showed that the population sizes of mammals, birds, fish, amphibians and reptiles have declined on average by 68% since 1970. In my lifetime, the common species that I grew up with around my garden and in the woodland and farmland that surrounded are now substantially rarer. These declines, and the less well-documented loss of abundance of many plants and invertebrates, mean that our ecosystems are less diverse, less resilient and less able to provide the ecosystem services that we rely upon.
David Attenborough’s latest documentary – Extinction: the facts – which aired on Sunday, provided a compelling account of how we are driving species to extinction through habitat loss, over-exploitation, pollution, invasive species and climate change. Extinctions are no longer a phenomenon of distant oceanic islands, but are increasingly occurring on continental land-masses, driven by landscape-scale clearance of natural habitats. This in turn is placing us at increasing risk from zoonotic diseases such as the current Covid-19 crisis. Our destruction of nature isn’t just a problem for future generations, it is catastrophe for us right now.
Image: Puerto Rican amazon; Image credit: Tom MacKenzie, US Fish and Wildlife Service Southeast Region
The Convention on Biological Diversity’s Fifth Global Biodiversity Outlook released this week reported that we have failed to meet in full any of the 20 ‘Aichi Targets’ adopted by the world’s governments a decade ago. We haven’t reduced the loss of biodiversity, addressed the pressures, adequately tackled the underlying drivers or effectively facilitated the enabling conditions. We are not currently on track to meet the CBD’s Vision of a world living in harmony with nature by 2050. We’re not even on the right train.
But it is not all doom and gloom, and there are plenty of reasons for hope and optimism. A paper in Conservation Letters last week showed that 28-48 bird and mammal species would have gone extinct without the conservation actions they received since the CBD came in to force in 1993. That is equivalent to avoiding the loss of 120 million years of evolutionary history for birds and 26 million years for mammals. The extinction rate in recent decades would have been at least 3-4 times higher without conservation action. This is one of precious few studies quantifying what a difference conservation makes at a global scale.
Another paper in Nature Communications this week used citizen science (eBird) data to quantify the extent to which protected areas in tropical forest biodiversity hotspots are effective at retaining bird diversity. It found positive effects of protection on forest-dependent, endemic, threatened and Near Threatened species, mostly driven by protected areas preventing both forest loss and degradation. These results show that despite all their challenges, protected areas contribute measurably to conserving bird species in some of the world’s most diverse and threatened terrestrial ecosystems.
A further paper in Nature last week showed that we can still ‘bend the curve of biodiversity loss’ driven by habitat loss while growing enough food for the expanding human population. If we increase the extent of land under conservation management, restore degraded land, implement sustainable intensification and trade, reduce food waste and meat consumption, more than two-thirds of future biodiversity losses can be avoided and biodiversity trends from habitat conversion can be reversed by 2050. The Global Biodiversity Outlook describes eight ‘transitions’ for themes such as food, forests, fisheries and climate, and the transformative changes and actions they imply, which are required for us to reverse current trends and achieve a more sustainable future.
Image: Gorilla; Image credit: Dr Stuart Butchart
I had the privilege to have contributed to each of these six outputs, working with many colleagues from CCI and beyond. I’m convinced that we need to communicate both the bad news (‘we’re destroying our natural heritage at an unprecedented rate’) and the good news (‘we know how to reverse these trends, it works when we try, and it is not too late’). We need governments to hear these messages loud and clear over the coming year or so as they negotiate a post-2020 Global Biodiversity Framework. Our future, and the nature of the world we pass on to future generations, depends upon them being sufficiently inspired by the successes to agree a framework that is bold enough to address the crisis.