Monitoring of biodiversity offsetting in Sweden

Sammanfattning

Biodiversity offsetting is a debated, yet increasingly used method to compensate for biodiversity loss caused by human activity, by creating gains somewhere else. However, offsets frequently fail to achieve their intended outcomes, and weak monitoring has been identified as a major contributor to this pattern. In Sweden,municipalities can apply voluntary offsetting under the Planning and Building act. Several Swedish municipalities have developed or are currently developing guidelines for biodiversity offsetting. The aim of this master thesis was to investigate how monitoring of outcomes of biodiversity offsetting, as applied by a Swedish municipality could be designed, using Uppsala municipality as an example. To address this question, I conducted two literature studies: a policy review of established offsetting frameworks, and a structured literature synthesis focusing on challenges and recommendations related to offset monitoring. My results confirmed the previously established finding that monitoring requirements are often limited even in well-established offsetting policies. The findings also showed that decisions made in the planning stage, such as the definition of counterfactual baselines and the choice of biodiversity metrics, highly affect the probability of offset success. A key finding was that simple habitat-based metrics commonly used to estimate losses and gains in biodiversity offsetting often fail to capture species-level biodiversity patterns, which may complicate the evaluation of offset outcomes. Therefore, an integrated approach is recommended, where monitoring design is closely linked to planning-stage decisions. Based on these findings, I provide recommendations related to offset monitoring in Sweden, including long-term monitoring, the use of biodiversity metrics matched to offset objectives, robust study designs coupled with control sites, and improved transparency and data availability.