David Williams

Responsibilities

• Programme Leader, Sustainability and Environmental Management
• Associate Professor

Research interests

I am a conservation scientist interested in preserving the incredible diversity of life on Earth while also looking after people. I largely do this by examining how different land-use strategies change the impact of food production on biodiversity. My background is in natural sciences, but I integrate social science techniques and am seeking to expand my collaboration with social scientists. In particular, my main areas of research at the moment are:

• Local and regional land-use strategies that provide everything that people need at the least cost to the natural world
• Global patterns of land-use change and the likely impacts on biodiversity
• Understanding and tackling the underlying drivers of biodiversity decline
• Maximising the impact of research

Local land-use strategies

Much of my research has focused on the "land sparing / land sharing" debate, which asks whether biodiversity is best served through small areas of high yielding agriculture (potentially bad for the biodiversity on the farmland, but the high yields can be used to 'spare' land for nature elsewhere), or larger areas of more wildlife-friendly farming (better for on-farm biodiversity, but requiring a larger area and therefore coming at the expense of natural habitat conservation).

Most evidence suggests that land-sparing is a less harmful approach for biodiversity and for carbon stocks, but there remains much we don't know: how do other benefits vary with land-use strateiges? How can we ensure that we capture the benefits of high-yield agriculture? Are there ways we can reduce the environmental costs of a land-sparing approach? Tackling these questions requires a multi-disciplinary approach and a willingness to face up to trade-offs between different objectives: it is unlikely that any one strategy will be optimal for all our objectives. 

Global land-use change

To safeguard biodiversity, we need to know where it is most likely to be threatened. Working with Dr. Michael Clark I have developed a high-resolution model to project where land-use change is most likely to occur. We then combine that with maps of suitable habitat for thousands of species to estimate where the impacts of agricultural expansion are likely to be the most severe. This provides vital data for conservation scientists, planners, and policy makers, to start to plan conservation responses.

Underlying drivers of biodiversity declines

A lot of conservation science tackles the immediate causes of biodiversity change: deforestation, hunting etc. This is hugely important, but as any undergrad will tell you, unless we tackle the underlying drivers of environmental change, we're unlikely to be successful. I am therefore investigating how we can try to reduce these underlying drivers, particularly the demand for agricultural land, through what we term "proactive conservation"—trying to stop problems before they develop.

In particular, Michael Clark, David Tilman, and myself have developed methods to link future projections of human food demand to possible changes in biodiversity. We can then tweak these projections, for example altering what people eat, or how efficient agriculture is, to see what has the biggest impact in different parts of the world.

Maximising the impact of research

The ultimate goal of conservation science is to preserve biodiversity and the benefits it provides to humanity. However, much of the time, we focus on the detrimental changes: How is biodiversity declining? Where? And why? Much more rarely do we ask "What are the concrete steps we can take to save species?". I want to change this! 

I worked for a year on the Conservation Evidence project producing a review of the world's research on what works for conserving birds, and have contributed to similar books on farmland conservation and a synthesis of what works in conservation. I am now working to ensure that my research focuses on the end goals of conservation, bringing in insights from economics, politics, and other disciplines, alongside conservation science, in order to provide actionable guidance for conservationists, policy makers, and local people, across the world. 

Qualifications

• PhD Zoology, University of Cambridge
• MSc Biodiversity Conservation and Management, University of Oxford
• BA Hons. Natural Sciences, University of Cambridge

Student education

I teach on several undergraduate courses and supervise research projects. I am always looking out for motivated students of any level—drop me an email with a research project plan if you're interested.

Research groups and institutes

• Sustainability Research Institute

Current postgraduate researchers

• Karen Castaño-Quintana
• Luis Gerardo Sánchez Soto
• Leon Noble