Re-Wilding in Review

Gary Dunnett, Executive Officer, NPA NSW

Re-wilding emerged on the Australian conservation scene atop John Wamsley’s feral-cat skinned hat.  Despite all the attention on killing cats and foxes, the core concept of rewilding is gentle simplicity itself – remove the competitors to native species, stop them from coming back, then give nature the chance to take care of itself. 

Why then, more than fifty years later, are we still grappling with whether re-wilding has a place in the NSW Protected Area Network?  I suspect the answer lies in our continuing unease about whether the environmental impacts of introducing hard barriers into ‘natural’ landscapes outweigh the environmental benefits of controlling feral species and re-introducing locally extinct wildlife.  

Collaboration between Government and Researchers

The NSW Government and National Parks and Wildlife Service (NPWS) have clearly endorsed rewilding as a keystone in their threatened species programs.  Back in 2014 a rewilding projects were announced in three NSW reserves, with an initial focus on the reintroduction of small mammals that had become extinct in NSW.  See Reintroducing locally extinct mammals   The projects were funded under the ‘Saving our Species’ program, a funding stream for threatened species protection in NSW. 

The University of NSW and Australian Wildlife Conservancies (AWC) were contracted to trial re-wilding programs in Mallee Cliffs National Park, Pilliga State Conservation Area and Sturt National Park.  Importantly, the trials included monitoring to evaluate effectiveness at species level and in terms of broader ecosystem function.  See About the project | Centre for Ecosystem Science

Another four reserves were identified for re-wilding projects in December 2020.  The new projects are significantly different to the trials.  The construction of feral free fences and ongoing management of the sites is to be managed entirely by NPWS rather than by contractors such as AWC.  The other difference is that three of the four projects are in reserves on the eastern side of the Great Dividing Range, and one of those is a small urban reserve.  This represents a major expansion from re-wilding’s roots in arid Australia. 

What’s involved?

The re-wilding projects all involve:

• identification of an area of appropriate habitat for the species proposed for re-introduction;
• installation of a feral proof fence in a cleared perimeter around that area;
• construction of tracks, storage facilities and other operational infrastructure;
• removal of feral species, especially cats and foxes;
• establishment of appropriate fire regimes;
• rewilding of target species; and
• monitoring, research and site maintenance. 

These works have significant environmental impacts, notably the need to clear approximately twenty metres of vegetation around the site perimeter.  There are also indirect impacts associated with the fence, such as disrupting fauna territories, impeding the movement of wide ranging species and limiting escape from catastrophic events such as drought, floods and wildfire. 

The justification for these projects is summarised in the Plans of Management for the latest sites (eg https://www.environment.nsw.gov.au/-/media/OEH/Corporate-Site/Documents/Parks-reserves-and-protected-areas/Parks-plans-of-management-other-documents/castlereagh-agnes-banks-windsor-downs-nature-reserves-amendment-plan-of-management-210032.pdf) They cite:

• The role of feral predators in Australia’s appalling history of extinction of small mammals;
• The need for feral free enclosures for the re-wilding of locally extinct species;
• The importance of protection from predators for surviving but highly threatened species; and
• The value of small digging mammals in restoring ecological health. 

Balancing benefits to the one against the many

There is no doubt that the return of Bilbies and Numbats to the NSW Protected Network is a thing of wonder.  As an organisation committed to the protection of our national parks and reserves, the question for NPA is how to balance the potential benefits of re-wilding with our clear responsibilities towards the species, habitats and landscapes that have survived the last two hundred and twenty years of loss and decline.  In other words, are the environmental costs of fencing and disruption to the free movement of wildlife acceptable?  

Like so many environmental issues the answer is ‘it depends’.  A key question is the significance of lost habitat in the context of a particular park and bioregion.  This became a central issue in the NPA response to the proposed feral free enclosure in Sydney’s Castlereagh Nature Reserve, in part because the cleared perimeter represented a relatively large proportion of the total area of the small reserve, but also because all of the vegetation was a threatened species and/or threatened ecological community.  (link to submission).  In this case our judgement was that the environmental costs were too high, and we recommended that an alternative site with existing fences and fewer values be selected. 

The fact that NPA has opposed the Castlereagh re-wilding proposal reflects the importance of considering each of the proposals on their individual merits, especially the environmental impacts associated with each proposal.  We can’t assume that every re-wilding proposal offers a net benefit, despite the current assurances of NPWS and Government. 

Nor should all re-wilding proposals be dismissed out of hand.  An amendment to the Yathong Plan if Management is currently on exhibition.  The Park Management Committee may well conclude that the low proportion of the park impacted by the fence, the abundance of the affected vegetation, and the benefits to existing species such as Mallee Fowl are sufficient to warrant our support. 

NPA is an effective advocate for conservation and protected areas because we make judgements based on the best available information before us, and don’t simply accept the confident assurances of government and their agencies. 

Irrespective of whether re-wilding is the right option for any particular reserve in NSW I do feel encouraged for one simple reason – the signal that threatened species recovery and environmental restoration are being recognised as core objectives in protected area management.  It is up to us to make sure that this momentum results in better outcomes for our parks and reserves.