Protected areas (PAs) are the leading policy to lower deforestation. Yet resistance by land users leads PAs to be created in remote sites, lowering impact. Resistance continues after PA creation, with both illegal deforestation and advocacy for PADDD, that is, reducing PA status (downgrading) or PA size (partial or full erasure, downsizing or degazettement). For the Brazilian Amazon, we estimate 2010–15 forest impacts of 2009–12 PA erasures, on average and for distinct states. Before panel-DID regression, to find similar controls we matched using static characteristics and 8–10 years of pretreatment deforestation. PA erasures should raise deforestation if erased PAs faced and blocked pressures. Consistent with this, three conditions for “environmental selection” yielded little short-run impact from PADDD: low pressures, unblocked higher pressures, and pressures blocked less by those PAs selected for erasures. Yet for “development selection,” with PA erasures in sites with pressures plus enforcement, PADDD yielded increased deforestation.

Protected areas (PAs) are a widely used strategy for conserving forests and ecosystem services. When PAs succeed in deterring economic activities that degrade forests, the impacts include more forest yet less economic gain. These economic opportunity costs of conservation lead actors with economic interests to resist new PAs, driving their sites away from profitable market centers and towards areas featuring lower opportunity costs. Further, after PAs are created, economic actors may want PA downgrading, downsizing, and degazettement (collectively PADDD). We examine reductions in PAs’ spatial extent – downsizings (partial erasures) and degazettements (complete erasures) − that presumably reduce protection. Using data for the entire Brazilian Amazon from PADDDtracker.org, our empirical analyses explore whether size reductions from 2006 to 2015 resulted from bargaining between development and conservation. We find that the risks of PA size reductions are raised by: lower travel costs (as implied by distances to roads and cities), which affect economic gains and enforcement; greater PA size, which affects enforcement; and more prior internal deforestation, which lowers the impacts of size reductions. These dynamics of protection offer insights on the potentially conflicting factors that lead to PA size reductions, with implications for policymaking to enhance PA effectiveness and permanence.