Guest blog from Dr Rob Field & Dr Richard Bradbury RSPB Conservation Scientists

How do you put a value on a nature reserve like Wicken Fen?

Man — despite his artistic pretensions, his sophistication, and his many accomplishments — owes his existence to a six inch layer of topsoil and the fact that it rains. ~ Anon.

The natural world has always provided for us, and throughout history we have valued that, but perhaps not monetarily.

Is it possible to put monetary values on some of the benefits conferred by nature?  It’s much easier to put values on some things than others.

As the proverb says, two of the chief benefits we get from nature are food and water, but we value one easily with money and the other less so.

Cultural benefits of nature are difficult put a value on

Flood control, water quality, regulation of climate and spiritual values are all examples of other benefits we get from nature, either directly or indirectly, but which are often not fully appreciated or accounted for within current economic models.

Yet a reduction or loss of these “ecosystem services” can have severe economic, social and environmental impacts. But, because they are not easy to value, they lose out to the more easily quantified services in many assessments of the value of particular land-uses to a community.

New Study puts a value on Wicken Fen nature reserve

To help put a value on ecosystem services such as the cultural benefits we get from nature  a group of experts (including the RSPB, the University of Cambridge, Anglia Ruskin Universities and Birdlife International) have developed a Toolkit for Ecosystem Service Site-based Assessment (TESSA) –  a set of methods that allow non-experts to make reasonable, scientifically credible estimates of some of the key ecosystem services a place may offer.  

Marsh harrier. Photograph by Chris Gomersall (

The study “Benefits and costs of ecological restoration: Rapid assessment of changing ecosystem service values at a UK wetland”, published this week, in Ecology and Evolution journal used the toolkit to value the ecosystem services offered by  a large area of restored wetland adjacent to National Trust, Wicken Fen NNR in Cambridgeshire.

The study shows that compared with its former use as intensively farmed arable land, restored wetland can offer many valuable resources to people, of more than equal value to the ‘lost’ agricultural production and in addition to safeguarding the spectacular wildlife the reserve itself hosts.

Wicken Fen nature reserve. Photograph by Paul Tuli

The restored wetland can reduce flood damage and carbon emissions to the atmosphere and increase recreational use and the availability of grazing land.

In 2011, each hectare of restored wetland was worth around US$200 more than if it had remained in arable cultivation, without taking farming subsidies into account, a cost to society.

Whilst we cannot survive without the food that arable land produces, there is still an awful lot of it available (even locally – The Wicken vision area is 5,300 hectares of around 230,000 hectares of arable land in Cambridgeshire – that’s about 2%) and farmers are pretty good at getting a lot of food from each of those hectares. This study demonstrates that whilst food is more important than its monetary benefit alone, so are some of the other things that land gives us that are not so obviously valued.

When tillage begins, other arts follow. The farmers, therefore, are the founders of human civilization. ~Daniel Webster, US Politician and Lawyer (1782-1852), Remarks on Agriculture

Using the toolkit more widely

TESSA has so far been used by conservation practitioners at more than 20 sites of conservation interest across five continents. The methods are applicable to a wide range of users, including natural resource managers, land-use planners, development organisations and the private sector. Find out more about the Toolkit for Ecosystem Service Site-based Assessment (TESSA)