The Guiana Shield is one of the most intact eco-regions in the world dominated by tropical rainforest. The ecosystems of the Guiana Shield region of South America (hereinafter referred to as the Guiana Shield eco-region) stretch from Colombia in the west through to the State of Amapá in Brazil in the east and includes French Guyana, Suriname, Guyana and a large part of Venezuela (figure 1).

It includes the large forested mountain systems that form the watersheds between the Amazon and Orinoco rivers, as well as savannahs and wetlands and is delineated by the Amazon River to the south, the Japari-Caqueta river to the southwest, the Sierra de Chirribiquete to the west, the Orinoco and Vichada rivers to the northwest and north and the Atlantic Ocean to the east (Priority Setting Workshop report 2003).