What Threatens Biodiversity?
Are we too worried about climate change to focus on the other problems we know about?
Yesterday, Nature published a noteworthy comment on the biodiversity crisis, written by researchers at the University of Queensland and the International Union for Conservation of Nature (IUCN). The piece is
based on a study of 8,688 species that are classified on the IUCN’s Red List either as threatened (vulnerable, endangered, or critically endangered) or near-threatened. The main finding is that the most prevalent threats to these species are overexploitation (affecting 72% of those studied) and agricultural activity (62%). This by itself does not seem surprising. What is interesting is that “climate change” as a threat to currently threatened species is much lower on the list, affecting 19% of the species studied.
These statistics can be taken in a number of ways. A response in the New Yorker by Michelle Nijhuis was titled, “Are Conservationists Worrying Too Much About Climate Change?” An entry in HuffPost Green ran under the headline, “Climate Change Is Not The ‘Biggest Killer’ Of Biodiversity.” These reactions pose a significant, but head-scratching question for conservation practice, law and policy: is there too much focus on climate change? At first glance, this sounds like a silly question, given that we have a long way to go in figuring out how to change our society to solve the climate conundrum. Yet if dialogue, research funding, and interest focus disproportionately on one bogeyman, does that distract from other challenges, like deforestation and habitat fragmentation or overfishing?
On the other hand, looking at the results compiled, it’s striking to see how many species are already threatened by the effects of climate change today. As James Watson, one of the study’s authors, suggested two months ago, extinctions happening now due to climate-related stresses (e.g. drought, melting ice, or sea-level rise) should be a strong wake-up call, challenging the narrative that climate change is something that will happen in the far-off future.
Of course, focus on environmental challenges is usually not a zero-sum endeavor. Climate change is closely connected to many of the other drivers of biodiversity loss. Clearing forests for expanded agricultural production, for example, simultaneously reduces habitat for forest species and emits significant quantities of greenhouse gases. With that in mind, policymakers should avoid looking at climate change in isolation. Natural systems are complex, but as much as possible, we need to pursue solutions to environmental problems that are least likely to exacerbate other problems — social, economic, cultural, and environmental.
More immediately, this study presents an important reminder that there is a great current need to focus on improving implementation, compliance and enforcement of existing environmental laws, equally and parallel to the push for international, national, and local climate commitments. Climate change is a threat not only through increased pressure on biodiversity, but also, of course, to human populations directly in coastal areas and indirectly through potential changes for agriculture. But even solving the climate crisis will do little to stem the tide of extinction if the other, “traditional” problems continue.