Putting a Monetary Value on Biodiversity

Ricardo Faustino de Lima has spent the last ten years studying how human activities affect the trees and birds of the tiny African island of São Tomé, in the ocean off Gabon.

But it was his photo of the elusive shrew Crocidura thomensis, spotted during a field work trip to São Tomé during his Lancaster PhD, that was chosen by the principality’s government to feature on their revised currency.

“I only found this species by chance while I was counting birds and trees in the mountain forest during my doctorate," recalls Ricardo.

“The local government wanted to have biodiversity on the banknotes with a focus on native species. The company producing the banknotes were struggling to find pictures, so when they found my photo of the shrew on the internet they contacted me to find if they could use it.

“I was delighted because it’s literally putting a monetary value on biodiversity.  A lot of the work we've been doing in São Tomé is to raise awareness, to let people know they have this unique biodiversity and that it is valuable.”

The islands of São Tomé and Príncipe, over 200 km off the coast of Gabon, have more unique species than the much better known Galapagos, despite being an eighth of the size.

“They are really unique in that sense,” says Ricardo. They are also densely populated, which means there is a high threat to biodiversity, but there’d been little research done on that topic, which is why I decided to make it the focus of my PhD.”

Ricardo sampled São Tomé’s trees and birds along a gradient of forest degradation: undisturbed native tropical forest; second growth forest, where cleared areas have become forested again; agroforests, where crops such as cocoa and coffee are grown under a canopy of trees; and non-forested areas, which currently cover just over a tenth of the island.

Native birds flourished most in the undisturbed forest, but persisted even in the agro forest plantations.  Native trees however were far more reliant on undisturbed forest. Both the second growth forests and agroforests were dominated by introduced tree species, and introduced birds dominated non-forested areas.

Since finishing his PhD, Ricardo has been trying to inform and influence local stakeholders to take measures to protect the country’s unique biodiversity. He has been collaborating with BirdLife International, a global partnership of conservation NGOs, to develop and implement a species action plan for critically endangered species on the island.

Ricardo is now a post doctoral researcher at the University of Lisbon. Part of his latest work has focused on the São Tomé Obô Natural Park, which contains the best preserved forests. The only way to reach it is on foot.

“We have surveyed a lot of poorly known areas of the island to gain knowledge of what is there, focusing on three of the most threatened bird species, but also paying attention to other groups and to the ecosystems as a whole, to identify ongoing threats. It’s thrilling, but also very tough. The maximum time I spent there was ten days in a row. You have to take all your food and equipment with you, up and down the hills, and it rains every day. It’s almost like Lancaster, but warmer.”

Ricardo and BirdLife are also working with local stakeholders to protect the Park and its wildlife.

“The most threatened species, the dwarf olive ibis Bostrychia bocagei, is being hunted, and it’s not even illegal. We’re working with local organisations to change that, and also with the hunters to understand how many ibises they are killing and to make them aware that this species occurs nowhere else and that hunting might soon drive it to extinction.”

“It’s ten years since I first went to São Tomé and, even though a short time, I feel people have a better understanding of the uniqueness of the biodiversity. I’ve been in a restaurant when people come to me and talk about native species because they know I am working with birds, so that is a good sign.”

Professor Jos Barlow, Ricardo’s supervisor at the Lancaster Environment Centre, said: “Ricardo was my first PhD student at Lancaster, and it has been a pleasure to see him develop research that highlights the unique biodiversity of Africa’s second smallest country – he is a role model for any student thinking about taking their research through to impact.”