Making decisions about how to use natural resources more sustainably demands data that many non-experts, especially in poorer parts of the world, lack. Now, a consortium of academics and practitioners in Cambridge has developed TESSA, a quick, low-cost evaluation tool that is being used across five continents.

Bringing together both socio-economic and biophysical, easy- to-measure indicators of ecosystem services for people who are not technically trained – and who might not have a lot of resources – was a big challenge.

Dr Iris Möller

Lots of other people who have used TESSA tell us it’s helped get all the stakeholders together and enabled them to understand each other’s point of view, which allows you to talk about these issues in a different way.

From food and clean water to erosion control and climate regulation, natural ecosystems give us a wide range of benefits. Loss of these so-called ecosystem services can have severe economic, social and environmental consequences.

To make informed choices about how to manage our natural resources, decision-makers across the world need accurate data. But established methods for obtaining this data are often too costly or complex to be widely used. So when a group of academics and practitioners from Anglia Ruskin University, BirdLife International, RSPB, Tropical Biology Association, UNEP-WCMC and the University of Cambridge met in 2010 to discuss the issue, they decided that there was a need they could help to meet.

According to Jenny Merriman, TESSA Coordinator at BirdLife International: “We realised there were a lack of tools for conservation practitioners on the ground that could be applied at low cost and fairly rapidly to provide useful information for decision-makers. The interactive Toolkit for Ecosystem Service Site-based Assessment – TESSA – emerged from that and filled that niche.”

The tool lets non-experts derive reasonable estimates of the key services that an individual site provides to society, both locally and globally, as Dr Iris Möller of the Department of Geography at Cambridge explains:“Some benefits may be quite local, such as a local community’s harvest of goods from a forest, but that ecosystem also provides a contribution to global carbon storage that counteracts the CO2 emitted by the global community.”

Sound science is at the heart of TESSA, so making that science accessible was crucial.

Replete with definitions and examples, TESSA effectively guides users through the process of, for example, calculating a tree’s biomass and the amount of carbon it stores through measuring its diameter at breast height.

As well as its science, TESSA teaches that not all ecosystem services can – or should – be valued financially.“We recognise that it’s not yet possible to put a monetary value on everything, so the toolkit provides guidance on how to present data in non-monetary and monetary ways, depending on the audience and purpose of the study,”Möller adds.

“TESSA is also based on the notion of an alternative state that you investigate through assessing services at a comparison site, and what would be the provision of these goods and services to the local and global community if you changed the state of the site, so you can compare the outcome and base your decision on that.”

Unlike many expert tools, TESSA promotes participation. At one site in Nepal, for example, TESSA has been used to understand how community management of a forest at Phulchoki has affected local livelihoods and carbon stocks, with results being verified by the community.

Community management had improved the forest for biodiversity, but using TESSA made it possible to work out how local people had benefited as well as who might have lost out. “We found there were some trade-offs. Local ownership provided benefits for local people,who set their own sustainable quotas, but logging companies lost out as did some ethnic groups,” says Merriman.

TESSA has so far been used at more than two dozen sites across five continents. But despite its success, users said that the tool would be even more useful if it wasn’t an unwieldy Word file, which is when Merriman and Möller turned to the ESRC’s Impact Acceleration Account (IAA).

IAA funding allowed them to gather more feedback from users such as BirdLife partners,  and work out how to take TESSA forward.“We were able to bring in a web developer, who advised us on various options, including apps  and ebooks, and we settled on an interactive pdf,” says Merriman.“So although the content remains broadly the same, it now has lots of pop-up definitions, references and embedded video and powerpoint slides that mean the detail no longer obscures the main flow.”

Launched at the Ecosystem Services Partnership conference in Costa Rica in September 2014,   the response has been“amazing”, she says.“The launch, with its news stories and social media activity, had a significant impact. In the 12 months before the conference TESSA was downloaded 600 times, but there have been more than 200 downloads in the first three weeks since the interactive pdf was launched.”

The team now plans to collect further feedback  to refine TESSA and even adapt it for different audiences.“We’ve discovered that businesses and consultancies are interested in the tool, which we hadn’t anticipated four years ago, so we are thinking about whether we should focus more on this area and what that means,”says Merriman, adding:“but what we have already achieved shows there is huge scope for this kind of tool.”

Merriman was also supported by the IAA to present TESSA to the Annual Symposium on Natural Capital organised by Stanford University in March 2016. This provided an excellent opportunity to showcase the development of the toolkit, and its use, and to allow engagement with a wider international group of experts and practitioners who are also involved in the development of improved methods for understanding ecosystem services, and ensuring that this knowledge is put to effective use in decision making.