On track to achieve No Net Loss of forest at Madagascar’s biggest mine
Meeting the Sustainable Development Goals requires reconciling development with biodiversity conservation. Governments and lenders increasingly call for major industrial developments to offset unavoidable biodiversity loss, but there are few robust evaluations of whether offset interventions ensure No Net Loss (NNL) of biodiversity. We focus on the biodiversity offsets associated with the high-profile Ambatovy mine in Madagascar and evaluate their effectiveness at delivering NNL of forest. As part of their efforts to mitigate biodiversity loss, Ambatovy compensate for forest clearance at the mine site by slowing deforestation driven by small-scale agriculture elsewhere. Using a range of methods, including extensive robustness checks exploring 116 alternative model specifications, we show that the offsets are on track to avert as much deforestation as was caused by the mine. This encouraging result shows that biodiversity offsetting can contribute towards mitigating environmental damage from a major industrial development, even within a weak state, but there remain important caveats with broad application. Our approach could serve as a template to facilitate other evaluations and so build a stronger evidence-base of the effectiveness of No Net Loss interventions.
| Item Type | Article |
|---|---|
| Open Access | Gold |
| Additional information | Check embargo when complete - put entirely on indefinate embargo until fully published This work was funded by the Natural Environment Research Council Envision DTP awarded to KD. |
| Keywords | Mitigation hierarchy, Environmental impact assessment, Net gain, Net posotive impact, Forest conservation, Biodiversity offset, Impact evaluation, Counterfactual, Statistical matching |
| Project | Envision DTP |
| Date Deposited | 05 Dec 2025 10:31 |
| Last Modified | 19 Dec 2025 14:55 |


