Rewilding is more than a conservation trend—it’s a science-backed approach to healing the planet’s landscapes and seascapes. Rewilding initiatives have resulted in demonstrable advantages, including increased biodiversity, the restoration of ecological functions, and improved climate resilience.
Nevertheless, the practice of rewilding is accompanied by challenges, encompassing scientific, ethical, and societal critiques. This article will examine prominent rewilding endeavors, the foundational ecological principles underlying rewilding, the challenges this practice faces, and elucidate why rewilding is considered a promising approach to mitigate biodiversity decline and climate change.
What is Rewilding?
At its core, rewilding is a conservation strategy aimed at restoring and protecting natural processes, ecological functions, and natural areas. While it can involve the reintroduction of key species (especially keystone or apex species), it also focuses on reducing and amending human influence over ecosystems, allowing natural dynamics such as grazing, predation, and vegetation succession to unfold freely. Baselines are critical in rewilding. Traditional conservation often aims to restore ecosystems to a relatively recent historical state. In contrast, rewilding focuses on restarting natural processes without aiming to recreate a specific point in time. It seeks to allow ecosystems to evolve dynamically, adapting to present and future conditions rather than preserving a static past.
Passive rewilding
Rewilding can take many forms. Passive rewilding might involve stepping back and allowing an abandoned landscape to regenerate naturally, whereas active rewilding often means reintroducing missing species or mimicking their roles. The underlying philosophy is to move away from intensive human management and let nature lead. A prominent example of this is the Knepp Estate in England.
Knepp Estate in West Sussex, England.
Once an intensively farmed estate, the Knepp Estate underwent a radical transformation in 2001. The landowners abandoned conventional agriculture in favour of a "process-led" approach to rewilding—letting nature take the lead rather than working toward predefined ecological targets. Free-roaming herbivores like Tamworth pigs, Exmoor ponies, red and fallow deer, and longhorn cattle were introduced to mimic natural grazing. These animals disturb the land in ways that encourage dynamic habitat shifts—creating a constantly evolving mosaic of grassland, scrub, and woodland. With no use of chemicals and minimal human interference, Knepp’s 3,500 acres have become a biodiversity haven.
Since the transition, species once absent from the landscape have returned or dramatically increased. Nightingales, turtle doves and purple emperor butterflies are now breeding on site. Knepp’s success has made it a national model—but not without controversy. Some critics argue it challenges conventional conservation models or risks neglecting certain species. Still, the positive cultural and ecological impact is undeniable.
Another compelling example of rewilding, this time set in the Scottish Highlands, is Trees for Life — an organisation leading one of the UK’s most ambitious landscape restoration projects. Their mission is to revive the ancient Caledonian Forest, once a vast expanse now reduced to scattered remnants after centuries of deforestation. Their approach blends active planting of native species such as Scots pine, birch, and rowan with encouraging natural regeneration, while managing herbivore populations like red deer to allow young trees to establish.
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Ancient Caledonian Forest, Abernethy, Scotland.
Beyond ecological restoration, Trees for Life actively involves local communities and volunteers, making rewilding not just an environmental effort, but a cultural one as well. Their integrated model highlights how ecological renewal and community engagement can work hand-in-hand to heal landscapes and reconnect people with nature.
Trophic rewilding
Ecologists define trophic rewilding as “an ecological restoration strategy that uses species (re)introductions to restore top-down trophic interactions and associated cascades, fostering self-regulating, biodiverse ecosystems”. In simpler terms, trophic rewilding often focuses on bringing back keystone species or “ecosystem engineers” whose presence has outsized effects on the environment. By reviving these top predators, large herbivores, or habitat-building animals, rewilding aims to reinstate the natural checks-and-balances that keep ecosystems healthy.
Rewilding Britain focuses on restoring natural processes with a strategy that involves reintroducing native species, restoring natural woodland, and revitalising degraded peatlands and wetlands. By allowing nature to take care of itself, Rewilding Britain seeks to create self-sustaining environments that require minimal human intervention but offer maximum ecological benefits.
Beaver Rewilding in the UK: Ecosystem Engineers at Work
Beavers (Castor fiber) are often called “nature’s ecosystem engineers,” and the UK’s recent experience shows why. Once native to Britain, beavers were hunted to extinction around 400 years ago. In the past two decades, however, rewilding efforts have brought this industrious rodent back to parts of England and Scotland. A landmark project was the River Otter Beaver Trial in Devon, which studied what happens when a family of beavers is allowed to live wild in an English river for the first time in centuries.
Castor fiber © Cavan Images / Shutterstock
As the beavers built their dams and ponds, they dramatically altered the river’s ecology. Researchers found that beaver dams slowed the flow of water, reducing downstream flood peaks in at-risk communities by a significant margin. Those same dams also filtered pollutants from the water, leading to improved water quality downstream. The ponds they created became biodiversity hotspots, with 37% more fish than in beaver-free areas. Across Europe, beaver numbers have grown from 1,200 to 600,000, helping restore wetland ecosystems.
In 2022, Britain granted beavers legal protection as a native species. Environment Minister Rebecca Pow praised their success: "improving biodiversity and water quality, mitigating flooding and making the local landscape more resilient to climate change." While some management is needed to prevent conflicts with human land use, the benefits of beaver rewilding are clear: they engineer healthier ecosystems and provide natural flood control in an era of climate change.
Climate Resilience and Carbon Sequestration
Intact, functioning ecosystems tend to be more resilient to climate extremes—an important consideration as we face more floods, droughts, wildfires, and shifting weather patterns. For instance, beaver wetlands in the UK have been shown to buffer against drought and flood, storing water in dry periods and slowing down torrents in wet ones. Similarly, the regrowth of forests and vegetation in Yellowstone’s valleys is stabilising stream banks and mitigating erosion, which could help the landscape cope with heavier rainfall or snowmelt in the future. But beyond local resilience, rewilding may play a significant role in climate change mitigation by enhancing carbon capture in ecosystems.
Emerging research highlights animals as “carbon ecosystem engineers”. A 2023 study in Nature Climate Change found that protecting or restoring wildlife populations can dramatically boost carbon sequestration. The researchers looked at nine species (including whales, sharks, wolves, wildebeest, sea otters, African forest elephants, and American bison) and found that healthy populations of these animals could facilitate the capture of an additional 6.41 billion tons of CO₂ annually. That’s 95% of the carbon removal needed each year to meet the Paris Agreement’s 1.5 °C climate target. How is this possible? Animals influence the carbon cycle through their foraging, nutrient recycling, and even their physical movements.
For example, wildebeest herds in the Serengeti keep grasslands short and cycle nutrients rapidly, leading to more carbon locked in soil; when their numbers collapsed in the mid-20th century, wildfires increased, releasing carbon. Whales feed at depth and release nutrient-rich waste at the surface, fertilizing phytoplankton (tiny plants) that absorb CO₂ – more whales mean more plankton and more carbon trapped in the ocean.
Rewilding, by restoring wildlife abundance, can supercharge ecosystem carbon sinks in forests, grasslands, wetlands, and oceans. Moreover, diverse ecosystems tend to be more stable and resilient, reducing the risk of catastrophic carbon release. A rewilded peatland, for instance, with its water table restored by beavers or natural processes, will hold onto its massive soil carbon stock, whereas a drained, degraded peatland might catch fire or decompose, belching CO₂. In this way, rewilding helps climate adaptation (through resilience to extremes) and mitigation (through carbon drawdown).
Challenges
Rewilding has captured the imagination of ecologists, conservationists, and the wider public — promising not just to conserve nature, but to restore it to a state of self-regulating dynamism. But this vision is not without its challenges. Nature is dynamic, not static, and ecosystems have shifted continuously under both human and non-human pressures. Rewilding initiatives such as Oostvaardersplassen in the Netherlands have shown how projects that foreground ecological processes can sometimes clash with local communities, animal welfare expectations, and wider public support.
Oostvaardersplassen, Netherlands.
Oostvaardersplassen is often cited as a flagship rewilding project. Managed by Staatsbosbeheer, this fenced polder landscape on the Flevopolder introduced hardy grazing animals — Konik ponies, Heck cattle, and red deer — to mimic a pre-modern river delta ecosystem once common in the region. The goal was to keep the landscape open and diverse, preventing it from reverting to dense willow thickets and encouraging biodiversity, especially among waterfowl and birds of prey.
But the absence of large predators and the restriction of migration due to fencing created a deeply artificial dynamic. Without wolves or lynx to control herbivore populations — and with no way for animals to leave in harsh winters — overpopulation led to mass starvation and culling. The winter of 2017–2018 saw some 3,300 animals die, sparking widespread public outrage. Critics argued that this was not rewilding but a poorly managed zoo. Others questioned the ethics of releasing domestic breeds to "mimic" extinct species, or the scientific legitimacy of any rewilding effort that imposes a fixed historical baseline on dynamic landscapes.
While criticisms of rewilding are valid and important, they refine rather than invalidate its central idea. Rewilding aims to establish the right conditions for natural evolution, not to replicate a past state. Oostvaardersplassen highlights the importance of scale and connectivity. The failed Oostvaarderswold corridor, meant to enable migration, demonstrates that successful rewilding demands landscape-level integrated thinking and corresponding political commitment.
What Rewildig at Scale Teaches Us
Humans have always been part of ecosystems, and for much of history, human activity maintained or enhanced biodiversity. However, in the past two centuries, impacts have become largely negative. Successful rewilding must acknowledge this history by working with local communities, respecting their traditions and livelihoods, towards ecological restoration. Ignoring this risks repeating past errors, such as the displacement of Indigenous peoples for "pristine" nature, as seen in early Yellowstone conservation. True rewilding restores both natural processes and human connections to the land, nurturing stewardship and resilience.
Gentian supports rewilding efforts by using its mapping and AI capabilities to help experts to gain a clearer understanding of baseline conditions. Our aim is to foster a broader understanding of ecological principles and their application in creating more resilient and sustainable solutions. Rewilding, with its focus on natural processes and ecosystem restoration, aligns strongly with our commitment to environmentally conscious practices. We believe that exploring such concepts contributes to a more informed dialogue within our field and can inspire innovative approaches. Rewilding emphasises the crucial role in promoting biodiversity, climate resilience, and a balanced future by working with nature.
