Since the Convention on Biological Diversity was agreed upon at the Rio Earth Summit, global Protected Area (PA) coverage has increased whereas commensurable financial commitments to manage PAs have not. Here, we question whether biodiversity offsets should act as a complementary funding mechanism where funding for PAs is inadequate. Based on the additionality concept that underpins offsetting, biodiversity offsets set in PAs could be considered as not additional since PAs are already protected by legal or other means, and in theory should be adequately financed and managed. In practice, however, many PAs are under increasing threat due to a lack of sufficient funding for staffing, infrastructure, and other basic operational necessities, which renders their management ineffective, resulting in further loss of biodiversity. In such cases, we argue that additionality from a financial perspective can be demonstrated, opening up the opportunity for offset financing to provide enhanced protection of PAs. Even so, the use of offsets for PA financing is not straightforward due to the introduction of new risks to existing challenges that offset face in general. We address four key challenges and highlight three advantages of using offset finance for improving PA management. We end by questioning whether the use of offset finance can deliver high-quality biodiversity offsets through existing PAs, and what this might mean for biodiversity conservation more broadly. We infer that this mechanism has the potential to boost financing for conservation and help governments meet some of their national and international biodiversity conservation commitments, including the realization of Aichi Target 11.
