Example of an actively restored site.
Photo credit: Josh Dorrough

By Laure-Elise Ruoso, Roel Plant, Stephanie Hernandez, and Josh Dorrough.

Read the full paper here.

Biodiversity offsets are intended to compensate for the impacts of land clearing on one site by improving biodiversity values elsewhere. Two broad approaches are used to compensate for impacts:

  • protecting habitats to avoid future loss or
  • restoring habitats, using passive or active forms of restoration. Passive forms of restoration focus on ending degradation by removing threats (e.g. stopping grazing activities). Active restoration is more intensive and includes the enhancement or creation of habitat and the reintroduction of plants and/or animals. Passive forms of restoration are more likely to be suitable on sites that are in moderate ecological conditions, while active restoration will be more adequate in low to moderate condition sites.

Various stakeholders are involved in assessing and managing offset sites: ecological consultants prepare management plans, government staff assess/approve them, and restoration practitioners implement them. Currently, we don’t know much about their perspective on the use of restoration in the context of offsetting. Therefore we talked with stakeholders involved in the NSW Biodiversity Offsets Scheme and the restoration industry. We focused on active restoration more specifically.

Stakeholders had differing views on the use of active restoration on offset sites. Some believed the preservation of good-condition habitats should be prioritised, rather than betting on uncertain restoration of future habitats. For others, active restoration was essential, as it likely increases the area of native vegetation. However, restoration also comes with risks. Some stakeholders warned against entrenching a false narrative that ecosystems can be destroyed because they can be actively restored. Others worried that good-condition habitats could be offset with larger areas of lower condition habitats to be (actively) restored. Considering the uncertainties surrounding active restoration outcomes, the restoration of lower condition habitats may never compensate for the loss of good-condition habitats.

Stakeholders also agreed that (active) restoration is highly context-dependent and often undertaken with only a partial understanding of the ecological processes supporting an ecosystem.They acknowledged that active restoration can be unpredictable and often requires flexibility and the use of “circumstantial creativity”, which can seem misaligned with offsetting schemes, where biodiversity gains need to be accurately predicted.

We found four conditions under which active restoration may be considered appropriate and feasible in the context of biodiversity offsetting:

  • Active restoration is only used on sites where less ‘intensive’ practices (i.e. passive restoration) do not succeed;
  • Good-condition and irrepleacable habitats are adequately protected, and active restoration is not used to justify the clearing of good-condition and irrepleacable habitats;
  • Active restoration is used on sites where it is likely to succeed within reasonable margins of uncertainty;
  • Ample room is created for intelligent tinkering and experimentation (separately from generating gains) to help reduce scientific and operational uncertainties related to active restoration in the longer term.