Conservation Letter Managing the risk of biodiversity leakage from prioritising REDD+ in the most carbon-rich forests: the case study of peat-swamp forests in Kalimantan, Indonesia

One major concern regarding the biodiversity impacts of Reduced Emissions from Deforestation and Degradation (REDD+) is “leakage” of threats from REDD+ to non-REDD+ forests, particularly if those forests storing the highest amounts of carbon – and thus prioritized under REDD+ – do not coincide with those most important for biodiversity conservation. This concern applies globally, and has been previously discussed in Indonesia, where the highest-carbon forests on peat are known to support lower species diversity and concentrations of threatened species than lowland mineral-soil forests. To help refine management of this risk, we discuss previously overlooked considerations regarding biodiversity threat leakage, suggest three strategies for managing leakage risk, and outline important questions to address with respect to these. We emphasize (1) the need to recognize intrinsic differences in threat displacement vulnerability among forests not currently protected/proposed to be protected under REDD+; and (2) that not pursuing REDD+ in high-carbon forests in an attempt to avoid leakage will not necessarily reduce this risk in low-carbon, non-REDD+ forests, due to the often high intrinsic vulnerability of these forests. Further to previous recommendations, suggested strategies for reducing risk of threat displacement include (1) focusing “traditional” conservation resources on the most vulnerable high-biodiversity forests not scheduled for protection under REDD+; (2) reducing costs, simplifying procedures and encouraging community-based approaches for pursuing REDD+ in low-carbon, high-biodiversity forests; and (3) developing more creative measures, especially fiscal and financial incentives, for protecting vulnerable low-carbon forests. Inter-disciplinary research is urgently needed to evaluate the feasibility and effectiveness of these strategies to successfully manage biodiversity leakage risk from pursuing REDD+ in high-carbon forests and, thus, for ensuring REDD+ achieves its potential for generating biodiversity conservation gains.