Ecological footprinting provides us with an invaluable tool for assessing human impacts on the earth’s natural and mineral resources, and on ecosystems. The concept of the global hectare and the contrast between what one person relies on to supply their wants, and what is actually available, is one which can be conveyed graphically to any audience.

A further contrast available through this method is of great interest to the Optimum Population Trust (OPT), namely the way in which the number of global hectares available to supply the needs of each person has reduced so alarmingly in recent years as the number of persons sharing those hectares has increased.

In 1961, with world population at three billion people, biocapacity was roughly three global hectares (gha)/person, while in 2001, with 6.15 billion people, per-person biocapacity was down to 1.8 gha. Despite strenuous efforts to reduce the size of affluent footprints – more fuel-efficient appliances and buildings, more materials recycled – the hoped-for reduction in the ecological deficit is constantly wiped out - not only by the quite proper increase in the meagre average footprint within developing countries, but by the sheer increase in the number of footprints anywhere.

There is no unmet need to reduce levels of consumption: whether rich or poor, people want more. In contrast, more than 120 million couples do have an unmet need for modern contraception (WHO statement, Lancet 2006) and each year there are “an estimated 80 million women who have unintended or unwanted pregnancies….” worldwide. Women in the countries experiencing the highest rates of population growth have little or no access to reproductive health services.

Each nation-state has a moral responsibility for overall ecological sustainability within its own borders. But when governments (or environmental organisations like WWF) are asked “How can we live more sustainably?” the response is about reducing the per capita footprint of their constituency and never in terms of gradually stabilising and then reducing the number of feet.

An absent human has no environmental footprint.

The much-advocated technological and life-style changes will never suffice. We urge the Global Footprint Network and WWF to adopt policies which give equal importance to population stabilisation and per capita impact reduction, in the huge challenge of living within Earth’s biocapacity.

Professor John Guillebaud and Valerie Stevens, Co-chairs, Optimum Population Trust

*Expanded Abstract, 2 February 2007