It is hugely reassuring to suggest that decisions should be evidence-based. It sounds safe, sane, sensible. It seems self-evidently right. What else could they be based on? Guesswork? Hope? Prejudice? As a result the concept of evidence-based policy is on the ascendancy everywhere. Politicians love it, because it sounds so reasonable. Policy makers love it because it implies that decisions can be rational, free of bias, proofed against sectional interest. Scientists love it because it offers the opportunity to feed ‘sound science’ into the ears of policy-makers. So it seems an obvious fact that evidence-based policy is a good thing: yet as Sherlock Holmes comments in The Boscombe Valley Mystery ‘there is nothing more deceptive than an obvious fact’. Some caution may be warranted, for there are deceptive layers hidden by the term that are easily overlooked.
We have spent a lot of time in the last two years thinking about evidence and its role in conservation. We came into this area of thinking with certain preconceptions. We both work in an academic environment, and spend most of our working days trying to sort good arguments from bad, clear writing from muddle, sound data from detritus. But we have also both worked outside academia, not least with communities in remote rural areas who have had little or no access to formal education. We have found expertise and insight in unconventional quarters.
We have learned a lot through this process, and the result is a short paper published in the latest issue of Oryx: ‘Conservation, evidence and policy’. We are delighted that Neal Haddaway and Andrew Pullin, as expert practitioners of evidence-based conservation, have written a reply to this, in which they politely take issue with some of the points we make. Oryx have very kindly agreed to make the papers open access for the next two weeks or so, and we hope you might like to read them.
Our Oryx paper focuses on the first two words in evidence-based conservation, considering what qualifies as evidence, and the relationship between evidence and conservation decision making that is implied by the word ‘based’. We argue in favour of a broad definition of evidence from a range of sources, and call for a nuanced understanding of the science-policy relationship that is captured by the term ‘evidence-informed conservation’. The idea of evidence-informed policy is well established in the development literature, which has had a lengthy and public conversation about the role of evidence (there is a superb summary on Duncan Green’s blog). We hope that our paper might trigger a similar public debate in conservation.
As we have thought more about evidence-based conservation since finishing our paper, we have realized that different meanings and interpretations of the final word, conservation, are also important. Most writing on evidence-based conservation sees conservation as a set of discrete management interventions in habitat. For example, conservationevidence.com defines a conservation intervention as ‘anything you might do to manage, protect, enhance or restore biodiversity. Interventions include types of habitat or species management, methods of species or site protection, methods of controlling invasive species, species reintroduction, captive breeding, legislation, and education programmes’. Thus the interventions to benefit wildlife on farmland reviewed by Dicks et al. 2013 include hedges, ditches, stonewalls, protecting in-field trees and creating scrapes. We have a much broader view of what conservation is, which is not based on specific interventions. We see it as ‘social practices that reflect choices about relations between people and nature’. Perhaps our different reactions to evidence-based conservation are as much as anything about our different understanding of what conservation is. ‘Evidence’ in the quantitative sense is useful for understanding grass buffers, but less so for understanding corruption in a forest department, and we become worried when the methods for the former problem are applied to the latter.
Thinking about evidence in conservation has led us far beyond the conservation literature, into the sociology of science, the anthropology of expertise, and disciplines from medicine to development studies. We have enjoyed the journey, yet retain some skepticism. We would welcome discussion with thoughtful fellow travellers.