John Topp Botanical Fund

The John Topp Botanical Fund is a designated CCT fund which aims to increase the understanding of the natural vegetation of the Chagos Archipelago.

Surveying the vegetation

In 2018 Sara Bárrios and Tim Wilkinson, a botanist and a spatial scientist from the Science Department of the Royal Botanic Gardens, Kew, travelled to the island of Diego Garcia with the aim of creating the first comprehensive record of the island’s vegetation. 

Once known for its coconut plantations, the vegetation of Diego Garcia is now a complex mix of abandoned plantation sites gone wild, and areas where native plant species still dominate. Prior to this field trip only very limited plant survey data was available for Diego Garcia. Using a suite of different survey techniques, both traditional and modern, the team surveyed the whole island and its various habitats.

The main aims of the expedition were:

  • Recording vegetation every mile by dividing the island into areas and defined survey lines using a traditional survey approach. These botanical data are available online via Kew’s UKOTs Online Herbarium.
  • Experimenting with capturing survey points with 360° photos. Annotated habitat images were recorded using a 360° camera, which are available to view online. The plant survey dataset collected will now be used to guide and validate the mapping of Diego Garcia’s vegetation using very high-resolution satellite images. 
  • Collecting images from a drone that surveyed a representative area of the island vegetation. For each flight the set of images have yielded high quality image maps, orthomosaics, and complementary photogrammetrically-derived digital surface models. Available here.
  • Collecting the first seeds from this overseas territory which have now been processed and accessioned at Kew’s Millennium Seed Bank, and several fungi which have been incorporated in Kew’s Fungarium.

The full report can be read here.

It is hoped the team can revisit the Chagos Archipelago in the future to continue this important work.

360 image of vegetation on Diego Garcia

360 image of vegetation on Diego Garcia

© RBG Kew