Playbook for Urban Biodiversity

S2. Phase out offsetting - and phase in 'onsetting'

Challenges with offsetting schemes and emerging alternative: Onsetting as a new approach to biodiversity conservation

Offset schemes have consistently failed to deliver net-positive biodiversity outcomes. This reflects the large areas required to genuinely offset losses of critical habitat, as well as various serious administrative challenges, including the difficulty in procuring suitable offsets, verifying that procured offsets are of equivalent biodiversity value, and maintaining offset properties in a way that their conservation value is retained. For example, the offset-funded Western Grassland Reserve in Victoria is around 10% of the size that it was promised to be, and is deteriorating due to inadequate maintenance. Even where schemes are capable of genuinely offsetting habitat, the effect of replacing a nearby biodiverse space with a distant offset property is still a loss in day-to-day access to nature – however equal that substitution may be on paper. This loss is particularly significant in urban areas which already have limited access to biodiverse natural spaces.

Internationally, numerous policies and approaches present viable alternatives for offset schemes. The concept of ‘onsetting’ is emerging as a new approach, whereby biodiversity is retained and enhanced on-site, rather than offset. Through the use of biodiversity-sensitive urban design approaches, built environments can be delivered that continue to have habitat value.