A Guide to Rewilding

Rewilding is becoming more and more popular and well-known as an approach to conservation. But what does rewilding actually mean, who supports it and how can you get involved?

 

Defining Rewilding

Rewilding is a type of ecological restoration aimed at increasing biodiversity and reinstating natural processes. While human intervention may be involved in achieving rewilding, the process aims to ultimately reduce the human influence on the ecosystem. The original definition of the term meant to use top-down trophic effects in order to return an ecosystem to what it was before human intervention. This means using predators or large herbivores to control the rest of the ecosystem. The “3 C’s” were also mentioned in the original definition – Cores, Corridors and Carnivores. This was before the beneficial impact of herbivores was fully understood, and outlined the 3 main areas that rewilding should focus on – core zones, with corridors connecting them, and carnivores to regulate the rest of the ecosystem.

 

 

The impact that the presence of a large carnivore can have can be immediately appreciated by anyone familiar with the reintroduction of wolves into Yellowstone National Park in the US. In the 1930s wolves were eradicated from Yellowstone and their absence took a lot of predatory pressure off of the elk. This lack of predatory stress meant the elk didn’t need to move around the park as much, resulting in heavy browsing of willow. Once wolves were reintroduced, they reduced browsing pressure on the willows. These trees are an important food source for beavers, which then started spreading and building more dams. These changed the hydrology of the streams in Yellowstone, making them more suitable for a range of fish species, while songbirds returned to inhabit the willow trees. The return of wolves also benefits scavenger species, who before were entirely reliant on elk dying during the winters, but now have food year-round. This trophic cascade is a brilliant example of the impact that a large mammal can have on an ecosystem.

Currently rewilding is much less focused on just the carnivores in an ecosystem. You can see from the example above that they are crucially important, however so are the herbivores! This means that the definition of rewilding has changed, and to make defining it even more confusing, there are a couple of types:

• Active rewilding involves active human intervention. An example might be removing human structures such as a weir in a river.
• Passive rewilding involves humans stopping any impacts they are having on an ecosystem. It is a very hands-off approach, with farmers abandoning land as an example. Natural processes then restore themselves.
• Pleistocene rewilding describes the approach where species that would have been present in an ecosystem during the Pleistocene (Ice Age) are reintroduced. The reintroduction of bison into Kent in the UK is a good example of this method.

 

 

So, how is rewilding different to conservation?

Rewilding is actually a type of conservation, as the main aim is to protect and to preserve wildlife and wild spaces. However, conventional conservation focuses on maintaining an area in its natural state, while rewilding aims to return an area from an ‘impacted state’ to its ‘natural state’. Both types of conservation are important, and ideally should be used in connection with the other. For example, if a species is under pressure and has reduced in numbers due to habitat loss, then protecting reserves through conservation work is extremely important, but so is establishing corridors between reserves. If the species cannot move beyond a reserve it will not be able to access resources such as food and mates, and ultimately its Red-List status won’t improve. These corridors can be achieved through rewilding areas that are currently unprotected.

 

Why doesn’t everyone agree with rewilding?

The major issue associated with rewilding is that the principles and ideas are often badly defined, which leads to misinterpretation. When incorrectly applied, rewilding can harm existing species and the biodiversity of an area. This can cause discontent among local communities and ultimately result in a loss of support for the approach.

 

 

Why is rewilding important?

In Europe at least 80% of the land is degraded, and less than 30% of rivers have a ‘healthy’ classification. Human activity is resulting in habitat loss and degradation across the globe. The United Nations have a 30×30 campaign through which large scale restoration of ecosystems will be achieved by 2030, in order to restore and conserve the world’s natural resources. The aim is to restore over 1 billion hectares and they have listed rewilding as one of the methods that will be needed to reach this goal.

Rewilding is now also beginning to be supported by organizations that aim to mitigate climate change. If you rewild farmland you are likely to have fewer large herbivores (think methane gas emissions) and more plants. There have also been studies on trophic rewilding that show that the roles different species have in an ecosystem can affect the amount of carbon that plants and soils can capture. Browsing and grazing can accelerate nutrient cycling which can then increase the productivity of plant species. Grazing of potentially flammable plants reduce the frequency of bush fires, lowering greenhouse gas emissions.

Rewilding can protect against the impacts of climate change through reducing the risk of flooding or soil erosion. Rewilded ecosystems also may create economic opportunities for local communities, therefore reducing the financial impact associated with the environmental hazards when they do occur. Another major benefit of rewilding is that it is very cost effective in comparison with conventional methods. The environment manages itself rather than needing constant human input.

All of these reasons mean that rewilding is becoming an increasingly more important method of conservation. More and more landowners are turning to rewilding as a method of increasing biodiversity. One brilliant example of this is the Knepp Estate in West Sussex, where Opwall run a field site. Joining us here for our field course is a brilliant way to learn more about rewilding and see the benefits for yourself!

 

 

Knepp is a pioneer in UK rewilding and has inspired many more sites to take up ‘wilding’ as a conservation approach. They took their animals off the land when the farm stopped being profitable, and instead decided to give the land over to nature. To do this they introduced red deer, fallow deer, English Longhorn cattle, Tamworth pigs and Exmoor ponies, in addition to the roe deer that were already present. They later also introduced beavers within a pen (as the UK government currently still bans the full reintroduction of beavers). All of these species are responsible for preventing vegetation succession in some way, and therefore maintaining the scrubland mosaic that is now found at Knepp. This has been hugely beneficial for biodiversity, and it has become home to some rare species such as turtle doves, nightingales and purple emperor butterflies among many others. A recent study also found that Knepp absorbs more CO₂ than conventional farmland, which is vitally important in terms of climate change mitigation.

 

Your future in rewilding!

As rewilding becomes an increasingly well-known and popular approach to conservation, the number of careers available on rewilding sites will only increase. It is important for rewilding sites to survey the biodiversity within them to show that the approach is effective. As of 2023, the Biodiversity Net Gain initiative in the UK means that any development projects must offset any habitat loss they cause. The government has also pledged £9 million to help local authorities to recruit ecologists. This means a huge creation of new jobs in ecology, and many firms are looking to rewilding in order to create new habitats. This means that job opportunities for ecologists familiar with rewilding are only going to grow.

 

 

Our field courses at Knepp are focused on enabling volunteers to take advantage of this by teaching a range of survey skills along with an understanding of rewilding and its importance as a conservation strategy. Why not come along and see for yourself?

 

 

All photos taken by Fran Anderson