Last week, the World Wildlife Fund released their annual Living Planet Report, which estimated that wildlife populations (including mammals, reptiles, amphibians, birds, and fish) have fallen by 60% between 1970 and 2014. This represents a staggering and tragic loss of non-human life and ecological heritage. But the loss of wildlife means more than that, according to the WWF. “Our health, food and security depend on biodiversity,” the report says, and “without healthy natural systems researchers are asking whether continuing human development is possible.” Mike Barrett, one of the authors of the report, puts it more bluntly in an interview with The Guardian: “This is far more than just being about losing the wonders of nature, desperately sad though that is. This is actually now jeopardising the future of people. Nature is not a ‘nice to have’ — it is our life-support system.”
In the widest sense of the word — nature as everything except humans — this is hard to disagree with. But framing the loss of wild species as a threat to human civilization and material well-being is a questionable proposition. The declines in animal populations documented in the Living Planet Report are tragic and painful news for nature and wildlife enthusiasts like myself. Yet it is not clear that the loss of species and populations, even at the scale we’ve seen in the last few decades, really endangers human material well-being. Overall well-being and quality of life certainly are affected, no doubt — less non-human life makes for a world that is less beautiful and exciting — but the same may not be true for material well-being.
Of course, there are ecosystem services like carbon sequestration and flood control that provide clear benefits to society, and this can sometimes justify protecting ecosystems as a whole. But as for the role of species diversity and abundance in enabling these services, the evidence is mixed. In some cases, such as with carbon sequestration, a greater diversity of plants can be a boon. But non-native, generalist species can often support an ecosystem service just as well as native species. Simplification of ecosystems can sometimes enhance service provision; this is the essence of agriculture. And for ecosystem services like flood protection and water quality, there is no clear relationship with biodiversity. A tree canopy and some undergrowth will do just fine in many cases. Even in cases where biodiversity enhances ecosystem function, like primary productivity, it might not improve the service, if there is no human demand for it.
It’s hard not to observe, for instance, that while populations of wild species have been thoroughly depleted in places like Europe, whose landscapes have been deeply transformed for millennia, Europeans are, overall, healthy, well-fed, and enjoy high living standards. Meanwhile, the world’s poorest and most vulnerable populations are often found in tropical regions rich in biodiversity, such as the Congo Basin. Furthermore, we all seem to be doing just fine without the megafauna that went extinct even before the emergence of agriculture, at least in part due to human pressures.
Some have suggested that this presents an “environmentalist’s paradox”: why has human well-being increased even as wildlife and natural ecosystems have declined? I’m not sure, however, that it’s much of a paradox. Humans through the ages have altered their environment to better serve their needs — and that has often meant converting natural habitats to cropland or favoring some species over others. For example, while there were also more sinister motives behind the near eradication of American bison, one simple driver was the fact that cattle were easier to raise and provided more food and higher profits.
I’m acutely aware of the fact that the stories we tell can influence the public’s support for conservation, and I am as dedicated as any other conservationist to finding narratives that can persuade people to care for wildlife. It is entirely understandable that many conservationists have embraced the argument that species should be preserved because they provide “life support” to people and societies. But I have a hard time arguing in good faith that further wildlife losses per se would prove catastrophic to the material basis of societies. And I worry that pushing the argument too far — that our lives depend on wildlife — could eventually backfire if it is later perceived as crying wolf. This could jeopardize the public’s trust in conservation scientists and practitioners. To avoid that, we need to reconcile ourselves to the thought that many wild animals, while priceless in the aesthetic and spiritual sense, might be dispensable in the material sense.
None of this is to say that appeals to instrumental values and ecosystem services can’t be justified in many cases. Conservationists need a diverse set of strategies for on-the-ground action and advocacy. But I do think it means that we need arguments for conservation robust to the possibility that wildlife might not be as materially important as we’d like to think.