Last updated 23 September 2007
The Ecological Consequences of Wilding as a long term conservation strategy
Report of a meeting of the British Ecological Society Conservation Ecology Special Interest Group held at Gregynog, Powys on 12th and 13th July 2007
The meeting started with an introduction to the title and the issues. The title of the conference – What are the ecological consequences of wilding as a long term conservation strategy – is number 78 in the top 100 ecological questions of high policy relevance in the UK identified by Sutherland et al in a paper in 2006 (Sutherland et al (2006) The identification of 100 ecological questions of high policy relevance in the UK. Journal of Applied Ecology 43 (4), 617-627)
It has grown out of an increasing interest in wild land and wildland conservation but what is wilding? It is defined in the paper as the conservation of sites using only, or largely, natural processes but what does this mean in practical terms? Does it meanecosystems will recover to a previous, richer state, move forward to a new state or simply stagnate and lose some current features? How ‘wild’ can ‘wildling’ be, or will there need to be intervention in systems, at least in establishment phases? How big do we need – can a garden be wild or do we need whole landscapes?
Wilding is also a rather emotive phrase – ‘wildling’ seems alien to the UKs rather cosy notion of nature – we simply don’t do wild! Conservation by natural process may be an alternative and delegates were asked come up with an alternative name. Finally the point was raised that one of the consequences of a wilding approach is that it does not fit in with the prescriptive approach to nature that underpins much of our current approach to conservation, and the legislation that drives it.
The introductory presentation can be download here (PDF 305kb)
Re-Wildling – The Dutch Experience – Frans Vera, Netherlands
The presentation can be download here (PDF 8.4Mb)
Frans Vera began the main presentations with an inspirational talk. Starting with a quick look at extinctions, Frans raised the ‘shifting baseline syndrome’ where chronic, slow and hard-to-notice changes in Nature happen, and each generation then redefines ‘Natural’ according to their own experience meaning that a degraded state of Nature is accepted as normal. Today, small scale pre-industrial agriculture has become the frame of reference for Nature conservation. We think that without farming there will be no nature and old fashioned agriculture becomes Nature management.
We were then taken on a tour of the Oostvardersplassen – a 6000 hectares wilding project in the Dutch polders. Rare species such as spoonbill, bittern, great white egret and white tailed eagle have colonised the area. Heck cattle and Konik ponies are used as proxies of the extinct Aurochs and Tarpan, and wild deer add to the grazers along with large flocks of greylag geese. All add to the biodiversity as part of Ecosystem Functioning leading to more resilience in Nature. After looking at our mental model of animal welfare the rates of mortality at the site were shown and compared with the Serengeti, where 30% mortality led to a stabilisation of the population – a situation that has reached similar levels at Oostvaardersplassen.
Climax vegetation was then looked at, and what it might have looked like with a full suite of natural herbivores. Examples of regeneration were shown with oak and thorny scrub acting as nurse species to allow regenerating trees to avoid browsing despite large numbers of browser species.
A river regeneration scheme –Project Stork – was our final example. This river floodplain wilding project grew out of the need to contain floodwater. The scheme has benefited many species and despite early doubts from local people it has now met with expectations and a general acceptance of natural habitat development.
And the future? – The need to develop biodiversity through ecosystem functioning.
Size and connectivity – modeling ecological needs – Chris Thomas. CIRRE, IRS, University of Wales
The presentation can be download here (PDF 228kb)
Chris Thomas looked at landscape scale questions associated with wilding. Starting with resilience and adaptability, Chris ran through a series of questions that require research.
Adaptive capacity followed - systems with high adaptive capacity are able to re-configure themselves without significant declines in crucial functions in relation to primary productivity, hydrological cycles etc.
Then we looked at ecosystem resilience - the capacity of an ecosystem to tolerate disturbance without collapsing into a qualitatively different state that is controlled by a different set of processes. We were then introduced to the concept of Multiple stable states and catastrophic regime shifts that may be possible but when are we dealing with this phenomenon and is re-wilding a regime shift? How much will we have to manipulate the system to move into the desired state? After regime shift, can manipulation /maintenance stop (i.e. system is resilient in the new state)?
Chris then looked at patch size & connectivity and asked can ‘wild’ land exist as parcels in a multifunctional landscape and is the UK ‘big’, big enough, or can all rewilded land be considered a patch in a matrix? Finally Chris looked at the matrix in which we are working – the quality of matrix is generally more important than corridors in promoting patch viability but can rewilding be successful without also ‘softening’ the matrix and can agri-environment schemes be utilised to achieve this?
Does rewilding need a different approach to matrix softening than managed conservation? Chris finished by running through some of the modelling tools that may be used to address these questions.
Rewilding - a field of dreams? - Kathy Hodder, Bournemouth University
The presentation can be download here (PDF 485kb)
Kathy Hodder introduced us to the forthcoming BES booklet, and took us through some of the definitions and concepts that it may contain. Looking initially at some elements of wilding:
Kathy then looked at two approaches to wilding:
‘Pleistocene rewilding’ involving the release of old-world megafauna and ecological proxies for extinct keystone species and
‘Self-willed land’ described as “…partial or total abandonment (‘re-wilding’)” or ‘the establishment of protected areas which are left to develop without human control’.
We then looked at the Ecological Issues associated with both approaches. Finally Kathy described the next steps in producing the BES Issues Booklet - Incorporation of feedback from workshop; Ensuring all interested parties consulted; Circulation of draft outline; Draft texts produced by working group; Circulation of draft texts and Issues booklet published.
Natural grazing as a management tool – Peter Dennis CIRRE, IRS, Aberystwyth, University of Wales
The presentation can be download here (PDF 2Mb)
Peter Dennis looked at Naturalistic grazing for conservation management. Re-wilding is reliant on top predators to regulate the size or distribution of grazing herbivore populations and on sites of large extent. Naturalistic grazing without predators is more generally appropriate to European ecosystems of smaller size, but the consequence of the herbivore populations for the conservation status of ecosystems is not predictable. Broader limits to acceptable change are accepted compared with prescriptive conservation management of sites but there are concerns about detrimental effects should there be an increase in the population size of grazing herbivores.
Several questions were raised - To what extent can commercial and traditional breeds of cattle and sheep withstand wintering outdoors without supplementary feed and built shelter? What breed characteristics are suitable for wetland, grassland, heathland or woodland or a patchwork composed of all these habitats? What size population is necessary to be viable and appropriate for the area, habitat and environmental conditions?
We were then shown how studies of closed populations of red deer, soay sheep and Chillingham White cattle provide useful insights. Peter concluded that there is a compelling case for a substantial research effort to inform conservation practitioners about appropriate species, breeds and situations where naturalistic grazing systems can be effectively applied and when interventions are necessary.
The missing lynx – restoring Scotland's forgotten cat- David Hetherington, Caringorms National Park
The presentation can be download here (PDF 3Mb)
David Hetherington looked at The Missing Lynx and took us through the possibilities of restoring Scotland’s forgotten cat. We were taken through the evidence for Lynx in Scotland and the UK, the changes in European distribution and how forest destruction was probably a major cause in the extinction of the Lynx in Scotland. Re-afforestation and current forestry targets, along with high deer numbers, means that conditions are now thought to be suitable for the species in Scotland.
We were then taken through evidence from re-introductions in Europe, and lynx – sheep interactions. David then described his work on habitat suitability modelling and connectivity analysis which concluded that the Highlands could support a viable Lynx population, with another smaller population possible in the Southern Uplands if connectivity was improved.
Re-instating ecosystem processes: using small organisms to good effect – Sarah Dalrymple, University of Aberdeen
The presentation can be download here (PDF 2.3Mb)
Much of the debate on (re)wilding our semi-natural landscapes has been dominated by the issues surrounding the introduction of large mammals either as herbivores or top predators. At the other end of the conservation spectrum, species-focussed management can often be criticised for lacking ambition resulting in protected, but stagnant, populations which are genetically and demographically isolated within a fragmented landscape. Sarah proposed that combining the two approaches will benefit both through enhanced biodiversity across large rewilded areas whilst making conservation of priority species more effective within a connected habitat. It will take a long time for ‘original-natural’ communities to re-establish, meanwhile many of our woodland flora may have already been lost.
Reintroductions should use local donor material to create metapopulations within a heterogeneous, but continuous, landscape. She concluded by describing the development of a new project which aims to do this by introducing small cow-wheat to ants, ants to small cow-wheat and both to new forests.
Plenary Discussion – have we got anywhere near answering the question? What further work is needed and other questions raised?
Peter Dennis, Chair
A lively discussion followed. Key points to emerge were: What will be our measures of success – what do we want and how do we measure it? Current conservation practice, and the constraints of Natura 2000 (partly as a fault of UK interpretation of ‘favourable status’) can be a block on change; Availability of land for large scale projects may change with changes in global economic drivers; Ecosystem services can be used as a selling point; In coastal areas there is already some acceptance of a more natural approach; Key threats and drivers at a landscape scale need to be identified and tackled; There should be more links between academics and practitioners and finally we should GET ON WITH IT!
A field trip on the following day looked at large scale management projects in the Berwyn uplands. We looked at peat bog restoration on the RSPB/ evern Trent estate with discussions on the possibilities and consequences of ‘wilding’ on the site and the possible consequences of climate change leading to a drying of the bogs (whilst being soaked by torrential rain) and then we retreated indoors to discuss plans for management of the adjoining large forestry estate.
Many thanks to all the speakers for the excellent presentations and to the participants for the lively discussions.
Thanks to Gregynog staff for faultless hosting, to the Centre for Integrated Research in the Rural Environment (Aberystwyth and Bangor Universities) for support and to Ecology Matters Ltd for providing administrative support and to the Wildland Network for help with publicity.
Mick Green. BES Conservation Ecology SIG Secretary. August 2007