Rewild or Restore – how about doing both?

James Bullock and Nathalie Pettorelli summarise their Perspective piece that highlight the potential for integrating restoration and rewilding agendas into whole landscape approaches.

As biodiversity continues to decline at an alarming pace, it is becoming more urgent to not only halt these losses but to reverse them. This reversal of losses, now commonly termed ‘nature recovery’, generally requires improving the state of terrestrial and aquatic ecosystems.

Traditionally this improvement has been done through ecological restoration, which in practice has involved creating a target ecological community, such as a wildflower meadow, a broadleaved woodland or a chalk stream. Detailed research and practical experience over the last few decades have delivered well-evidenced methods for creating these target communities using approaches such as nutrient stripping, seed sowing, tree planting or substrate modification.

Rewilding vs Restoration

Rewilding has emerged much more recently as an alternative approach to nature recovery.

While some of its methods might also be used in restoration, such as allowing natural colonisation of trees, the aim is different. Rewilding is not focused on creating a target ecological community but on allowing the development of ecosystems that are governed by natural processes rather than human management. The aim is for a well-functioning and resilient ecosystem, not for a particular identity.

For example, a wildflower meadow might be restored by sowing particular plants and managing by traditional hay-cutting and grazing. By contrast, an open ecosystem might develop in a rewilding project that allows a variety of large mammals to roam and graze freely. Similarly, natural colonisation by trees can be used in restoration, but with the aim of creating a broadleaved woodland (i.e. ‘passive restoration’). Natural colonisation for rewilding may lead to woodland, or possibly a more savanna type ecosystem of trees, scrub and grassland.

Wildflower_Meadow_-_geograph.org.uk_-_8182 — Wildflower meadows such as this may be restored and managed through human intervention for a specific ecological community or “left” to rewild into a well-functioning and resilient ecosystem © Nigel Homer

Rewilding is much debated for many reasons, but partly because it is a departure from the very controlled approach to conservation that has predominated in regions such as western Europe.

It is clear, however, that restoration and rewilding each have value and have particular benefits for practitioners and nature. Because they focus on different aspects of biodiversity (restoration on species composition, and rewilding on ecosystem functioning), restoration and rewilding could work in synergy. This will generally be at a landscape level, or at least over several contiguous sites, to allow the processes to interact positively.

For example, restoration efforts can be focused on a few sites to create a range of ecological communities (such as grassland, scrub and woodland) and rewilding efforts involving no intervention or free-range grazing can be in the remaining landscape. This allows the setting of the landscape on a complex trajectory, with the restored sites ‘seeding’ the landscape with a range of communities, and the rewilded areas facilitating the flow of species between restoring sites while developing in their own idiosyncratic way. In combination, this allows a dynamic landscape that is diverse and resilient to environmental change.

eso312244-fig-0001-m — Synergies between restoration and rewilding

Another example could be a landscape that’s allowed to rewild by stopping human interventions but with a few small areas where restoration takes place and includes the use of locally extinct species (e.g. of trees). The restored areas provide a source of seeds and animals to colonise the rewilded areas naturally which may be particularly valuable in nature poor landscapes, such as post-industrial or previously intensively farmed, where there is little biodiversity to start off the rewilding. Using small scale restoration is cost effective and in combination with rewilding has impact over an area much larger than that restored.

eso312244-fig-0002-m — An example scenario comparing the (b) outcomes of restoration, (c) rewilding and (d) rewilding with restoration in an expansive forested landscape nature has been degraded. In (b), restoration is being used to recover biodiversity in patches where intensive land management and reintroductions are concentrated. In (c), a rewilding approach is being considered across the whole landscape. Under (d), restoring and rewilding approaches are applied simultaneously. The matrix surrounding the restoration patches is where rewilding is promoted to improve ecosystem functioning, and the restoration patches themselves can act as sources of colonists for the matrix

More generally for practitioners, linking restoration and rewilding could draw on the substantial knowledge of the restoration community, which could help build “know how” for rewilding. Rewilding could also provide inspiration for restoration efforts to be bolder and go large-scale, which is especially important under rapid global change.

To ensure that these benefits can be reaped, the restoration and rewilding communities need to come together, inform each other, and develop a shared agenda for nature recovery. This also requires policy support, but while there is increasing support for restoration in international and national legislation, there remains limited explicit reference to rewilding.

The time is right for governments and agencies to start facilitating the coordination and integration of rewilding and restoration and to provide the funding and tools for practitioners to develop exciting new approaches for nature recovery.

Read the full Perspective: “Restore or rewild? Implementing complementary approaches to bend the curve on biodiversity loss” in Issue 4:2 of Ecological Solutions and Evidence.