“Rewilding: The radical new science of ecological recovery”.
That’s the title of the new book written by Paul Jepson and Cain Blythe.
The question that jumps to mind is whether it’s really so radical. Or can we rewild the world?
To most people, rewilding is still a new approach. It evokes images of wild animals and untamed nature. But these images out of context are misleading and don’t do the ideas behind rewilding justice. To rewild the world we have to see rewilding more as a philosophy that strengthens our relationships with nature and aims to restore nature as our ally.
Because Rewilding has an immense potential for solving environmental challenges including climate change and biodiversity loss and people’s attitudes towards nature.
This post gives a brief overview of rewilding and its implications for nature and modern human societies. For everybody who wants to learn in more detail about it, I can recommend Jepson’s and Blythe’s book .
The world we live in
As humans we have altered our planet’s land- and seascapes on a much larger scale than any other species. Human impact has disrupted the functionality of many ecosystems.
We have exploited our soils and fished our oceans empty. Our rivers are straightened and their natural flow is blocked. We have transformed wild and diverse forests into monocultures. We have drained wetlands and turned them into agricultural fields. Our cities keep growing and nature has to make way.
As a result many species, plants and animals, are struggling to survive. And by now we find ourselves in the middle of a climate crisis and the 6th mass extinction.
The recent Peoples Climate Vote Results published by the UNDP show that 64% of polled people recognise the current state of our climate as an emergency. More than a half (54%) agree that policies addressing conservation of forests and land are the most important. But nature with functioning ecosystems is not only crucial for our mere survival. A healthy environment is also crucial for a life worth living.
Although at this point the importance of nature conservation is widely recognized, it seems that simply conserving nature is not enough anymore. By now we have lost much of our nature and disrupted the functionality of many ecosystems. Protecting what is left is not enough. Instead we also have to think of strategies of how we can bring nature back and restore the functionality of degraded ecosystems.
It’s time to act and the UN declared the current decade from 2021 to 2031 as UN Decade on Ecosystem Restoration. And rewilding the world is one way to do it.
So what is rewilding and how can we rewild the world?
By now there is a lot of scientific and popular science articles on rewilding (sometimes also referred to as wilding). But rewilding is not only a theoretical concept. Ideas of how to rewild the world are already put into practice by pioneering conservation initiatives .
Exact definitions and approaches may vary depending on the person you ask and the context. And they may change over time following new insights.
In Europe, one of these pioneers is ‘Rewilding Europe’. They define rewilding as follows:
Rewilding is a progressive approach to conservation. It’s about letting nature take care of itself, enabling natural processes to shape land and sea, repair damaged ecosystems and restore degraded landscapes. Through rewilding, wildlife’s natural rhythms create wilder, more biodiverse habitats. 
Another definition of rewilding that does not only focus on how to rewild nature but also on how to rewild humans comes from ‘Rewilding Britain’:
[Rewilding is about] restoring ecosystems to the point where nature can take care of itself, and restoring our relationship with the natural world. 
Rewild the world by letting nature do its thing
So basically rewilding is about letting nature do its own thing. We might give it a helping hand in the beginning to create the right starting conditions. We can for instance remove dykes and dams or help with the reintroduction of a lost species. But after that we let nature take care of itself. That means that rewilded areas need none or only very little human intervention .
Unlike more traditional forms of nature restoration, rewilding doesn’t have a clearly defined end point. It is not about restoring nature to a certain stage and then make sure that it stays that way. Rewilding is about restoring natural processes, and hence, establish healthy and functioning ecosystems. That way landscapes and seascapes are allowed to become wilder.
We have put many species on the brink of extinction. Many ecosystems that once were home to a rich biodiversity are now dominated by a few species only. And many areas lost important keystone species (species that have an over proportional high impact on the ecosystem).
In nature conservation the reintroduction of species to bring back locally extinct species or reinforce existing populations is a common practice. Traditionally, the focus is on endangered species .
Rewilding, however, has a slightly different approach. Most rewilding initiatives focus on bringing back the ‘big stuff’ high up in the food chain. Good examples are projects focusing on large grazers such as the European bison or apex predators such as wolf and lynx .
Rewild the world: 4 types of rewilding in science and practice
From a more scientific point of view we usually distinguish between 4 types of rewilding: Trophic rewilding, Pleistocene rewilding, translocation rewilding and passive rewilding. On a more practical note, I would add two more types : Urban rewilding and human rewilding.
So let’s have a look at the different types of rewilding and some practical examples of how to rewild the world.
Trophic rewilding aims at restoring top-down trophic interactions (the links between predators and their prey) and trophic cascades (the effect on different levels of the food web). Large predators fulfil a regulatory role in the ecosystem.
They are crucial for functioning of and resilience of ecosystems . Without them the food web is incomplete leading to an imbalance . Over time the ecosystem degrades, as it doesn’t function anymore as it is ‘supposed’ to.
The most famous example of trophic rewilding is probably the reintroduction of wolves to the Yellowstone National Park. It’s often cited as one of the best examples of how reintroducing carnivores can help to bring degraded habitats back to healthy and functioning ecosystems .
Wolves in the Yellowstone National Park
Before their reintroduction in 1995, wolves have been absent from the area for several decades. Their absence had a negative impact on the ecosystem functioning. Due to the absence of their natural predator elk populations got out of control. Increased elk grazing caused a decline of upland aspen and riverine cottonwoods. Similar to the elk population, coyote populations increased. This resulted in increased predation of smaller species and put a huge pressure on these small animals.
10 years after their reintroduction the wolf population counted more than 300 individuals and the ecological benefits surpassed all expectations. The numbers of elk had decreased and their grazing behaviour had changed as a response to the increased predation risk. Aspen, willow and cottonweed trees recovered. Taller willows at the riverside had a positive impact on aquatic ecosystems. This caused the comeback of beavers (previously more or less extinct in the area).
The wolves also killed and displaced coyotes. The coyote population in the park declined, helping fox populations to recover. Wolves mainly prey on old or sick individuals. That way they keep the elk population healthy (they can do that a lot better than hunters).
On top of that, increased elk kills also benefitted all different kind of scavengers including grizzly bear, cougar, wolverine and raven
Around 12000 years ago, towards the end of the Pleistocene era (also known as Ice Age), many megafauna species became extinct (most likely due to hunting). In the Arctic the disappearance of the megafauna caused an ecosystem shift. Open landscapes that were formerly roamed by mammoths, bison, horses, reindeers, lions and wolves changed into the vast tundra and taiga ecosystems that we know today.
The idea behind Pleistocene rewilding is bringing back the lost megafauna. But many of the large animals from the Pleistocene era are gone forever. So just reintroducing these animals isn’t possible.
Ideas go as far as scientists looking into the possibilities of ‘recreating’ a mammoth opening up the idea of ‘de-extinction’. With such wild plans the exact consequences are very hard to foresee and Pleistocene rewilding definitely is one of the more controversial forms of rewilding .
There is currently only one example of Pleistocene rewilding in the world: Siberia’s Pleistocene Park. Close to the Russian frontier town of Chersky thawing permafrost revealed astonishing amounts of bones from the Pleistocene megafauna. Bones of bison, elk and mammoth suggest that the tundra once supported a rich megafauna. It seemed that this area once used to be a ‘mammoth grassland steppe’.
Permafrost scientist Sergey Zimov introduced the idea of the Pleistocene Park as an experiment. The aim was to learn more about the role of Pleistocene mammals in maintaining their own ecosystems and to learn how to restore and extend Pleistocene-like grasslands to mitigate the progress and effects of global warming. He fenced of a 1000 ha area and introduced species like hardy Yakutian horses, elk, musk ox and bison to resemble Pleistocene fauna. It is an exciting project. However, scaling up might be difficult. The area is very remote and brining in large quantities of big animals isn’t an easy task.
Translocation rewilding focuses on the reintroduction of species in order to restore dysfunctional ecological processes.
But in some cases that is impossible. If the target species got extinct it might be necessary to look into current descendants or functional equivalents of lost species instead.
An example of translocation rewilding is the Iberá project in Argentina. The area is located in the Argentinean province of Corrientes, an area that in the past lost many species including birds and large mammals.
Many animals including jaguar, giant river otter, tapir, collared and while-lipped peccaries, the giant anteater, bare-faced curassow and green-winged and violet macaws disappeared from Corrientes. And some of them disappeared from the world for good. Other species including pampas deer, maned wolf, ocelot, paca and the red-legged seriema survived in the area but their populations suffered great reductions.
Since 2007 rewilding efforts focus at bringing back locally extinct species and reinforce the weakened populations of the survivors. By now the area of the Great Iberá Park is Argentina’s largest natural area and in 2018 the first jaguar cubs in 70 years were born in Corrientes.
But rewilding does not always require human’s helping hand. Passive rewilding is not so much about actively doing things than rather not do them. It’s more about reducing human control of landscapes. That way nature gets the room to find its own ways.
In an ideal situation the above-mentioned types of rewilding eventually all get to this state. Passive rewilding happens intentionally but often also unintentionally in many areas of the world. Typical passive rewilding areas are marginal lands abandoned by farmers 
Other forms of rewilding the world
Even though scientific research focuses on these four categories, there are other forms of rewilding that don’t fit into one of these categories. Yet they are important. Two examples are urban rewilding and human rewilding.
With current trends of urbanisation, urban rewilding becomes increasingly important. Even though urban rewilding takes place at a much smaller scale it could play an important role in the future. Urban rewilding is still in its beginning stage. But it could have a big impact on local biodiversity and climate and the liveability of modern cities .
At this point urban rewilding focuses a lot on the potential of green roofs and other possibilities to increase the size of nature areas in the city . We also already wrote about green urban spaces and tiny forests.
More and more research also confirms what many of us know already: Being in nature makes us feel good, it improves our mood, helps us to deal with anxiety and stress and boosts our immune system .
Urban rewilding initiatives often depend to a large extent on active engagement of the local communities. At the same time they aim at giving people easy access to nature. And this is where the idea of human rewilding comes in.
Human rewilding builds on the idea of reconnecting humans with nature. Many people feel that they have lost touch with nature. We cannot rewild the world without restoring our human connection with nature.
Bringing back that connection could have a huge influence on how we treat our planet and other species.
But rather than being its own form of rewilding, human rewilding is seen by many rewilders as inherent part of other rewilding initiative.
Creating win-win situations
Unlike more traditional forms of restoration ecology, rewilding has a strong focus on reconnecting people with nature and making nature an integral part of our everyday life.
The idea is to rewild the world and ‘create’ landscapes and seascapes where human and non-human forms of life can thrive. It’s not about creating fenced-off natural areas. Instead, humans should get access to nature (as much as possible).
Rewilding has the potential of creating self sufficient systems that fit into our modern lives and societies. Such systems create environmental and social benefits and can be a source of income for local communities.
A typical example are initiatives with a strong focus of combining rewilding with nature-based tourism.
Rewild the world: Radical or needed?
So getting back to our initial questions: Is rewilding really such a radical approach? And can we rewild the world?At first sight it might seem like it.
Already the word ‘rewilding’ evokes many different emotions. Those who want to reconnect with nature feel attracted to the idea of easily accessible wild nature. But to others the idea wild animals roaming around seems daunting.
But once we leave traditional definitions of what ‘wild’ means behind, rewilding is actually not that radical anymore.
Rewilding aims at restoring the functionality of ecosystems and our connection with nature. It looks at the whole system. Rewilding initiatives don’t just look at nature but also the society. Rewilding aims at finding solutions that benefit all forms of life. Is that really so radical? I don’t think so.
Let’s rewild the world together
Shall we rewild the world together?
Would you like to learn more or get involved?
Or do you even have some rewilding experience that you would like to share with other like-minded people?
Join us on the ‘Rewilding Professionals’ group on LinkedIn.
Would you like to learn more about it? Get in touch!
References and further Reading
 Jepson, P., & Blythe, C. (2020). Rewilding: The radical new science of ecological recovery. London: Icon.
 Rewilding Britain: https://www.rewildingbritain.org.uk/explore-rewilding/what-is-rewilding
 The True Nature Foundation: https://truenaturefoundation.org/what-is-rewilding/
Plesitocene Park: https://pleistocenepark.ru/
Iberá Project: https://rewildingargentina.org/ibera-project/
Photo credits: Featured image: Red-and-green macaw © Matias Rebak – Rewilding Argentina
All other photo credits are indicated below the images.