Biodiversity & ecosystem services: Birds, bats, bees, and cocoa trees

Human populations are increasing rapidly and consumption is intensifying around the world. Agricultural expansion to meet these demands is the leading cause of habitat loss across the rainforests of Africa, and unfortunately biodiversity, which provides critical ecosystem services, is being lost at an unprecedented rate. Disadvantaged rural African farmers, who generally make less than £1 per day, rely on the ecosystem services provided by biodiversity, and are being increasingly impacted by their loss. Realisation of this crisis has created an urgent need to balance agricultural production with biodiversity. These two objectives are not disjoint, and indeed, biodiversity can play an integral role in increasing agricultural yields—sustainably. To achieve balance, we must manage ecosystems for species that provide support for crops (“ecosystem service species”, e.g. species that provide pest control) as well as those that encourage biodiversity (“keystone species”), and especially those that provide both functions (“cross-over species”).

To truly work towards this balance, we must first understand the food web, because species vary greatly in their value for agriculture and biodiversity services. For example, in North America, oaks support > 10x higher richness of butterfly and moth species than most other tree genera. Bird and bat consumption of insects in Indonesian cacao plantations increased crop yield by 31%. Beyond this, we need to understand how farmers make land use decisions and what their financial requirements are.

This project is using state-of-the-art genetics methods, sophisticated community modeling, and implements economic theory to investigate:

1) What community compositions are possible for a real ecosystem and how do they rank in terms of biodiversity, agricultural production, and farmer income?

2) What management actions would push the system towards communities that are both biodiverse and produce high farmer income?

3) What incentives are needed to encourage farmers to adopt these desirable management actions and how can these incentives be sustainably funded?

• Jarrett C, Smith T, Claire TTR, Ferreira DF, Tchoumbou M, Elikwo MNF, Wolfe J, Brezeski K, Welch AJ, Hanna R, Powell LL. 2021. Bird communities in African cocoa agroforestry are diverse but lack specialized insectivores. Journal of Applied Ecology 58:1237-1247.

• Ferreira D, Torrent L, Welch AJ, Wolfe JD, Brzeski K, Powel LL. 2020. First record of a piebald Bates’s Slit-faced Bat, Nycteris arge (Chiroptera: Nycteridae) from Equatorial Guinea, Central Africa. Journal of Bat Research & Conservation 13:88-92.