Rewilding: Case Reports and Lessons for the 21st Century

Brief Overview

BY Sara Ord

Rewilding has emerged as a global movement to restore ecosystems, a core pillar of which is the reintroduction of species playing crucial roles within these. Over the course of the last half-century, rewilding initiatives have spanned the globe, being met with tremendous success – thereby showing the promise and potential of rewilding as a key conservation strategy.

Inside this Article:

Rewilding: A Definition, A History

Stemming from Proto-Germanic wildia, the Old English wilde reflects a “natural state, uncultivated, undomesticated, uncontrolled” – wild-doer-naess thereby reflecting a place of autonomous, self-willed nature and animals not under human control – untamed.

In response to a growing threat of ecological collapse, buoyed by a heightened awareness of whole-systems ecology, rewilding was initially introduced as a concept in the 1990s – first discussed in a Wild Earth essay (1992) by American environmentalist Dave Foreman: “It is time to rewild North America; it is past time to reweave the full fabric of life on our continent”.

Rising above the traditions of conventional restoration ecology, rewilding emphasizes landscape-scale restoration, including the reintroduction of keystone species – floral or faunal organisms crucial to maintaining the balance and diversity of a complex ecosystem. Well-aligned with the United Nation’s Decade of Ecosystem Restoration, rewilding as such reestablishes species that have been driven out of an ecosystem, prior to stepping back and letting nature take its course – galvanizing the massive, self-directed restoration of entire terrestrial and marine ecosystems.

First leveraged as a conservation strategy nearly a half-century ago, rewilding projects have been met with budding success despite responding to complex sociopolitical factors and various funding schemes – letting as such emerge a few fascinating themes and perspectives on rewilding in the 21st century.

5 rewilding case reports from the last half-century

1995: Wolves into Yellowstone National Park, Montana, USA

Up to half a million wolves once roved America, but heavy European overhunting led to their total extirpation by 1926. Without the checks and balances of this apex predator, Yellowstone National Park grew rampant with deer, whose overgrazing compromised the fragile balance of the local ecosystem. In response, nearly 70 Canadian wolves were reintroduced to the park in 1995 and 1996 – catalyzing a trophic cascade successfully rebalancing the Yellowstone landscape. Deer populations were reduced and the local vegetation reestablished, enabling birds and beavers to return. Beavers’ dams served as conducive habitats to otters, ducks, and muskrats. The wolves also hunted coyotes, allowing for the reemergence of rabbits and mice, in turn feeding foxes, weasels, and badgers– while carcasses nourished bears, bald eagles and ravens. As of December 2021, the greater Yellowstone region is home to over 500 wolves, forming a vibrant ecosystem absolutely brimming with life.

The reintroduction of wolves to Yellowstone National Park was the first widely recognized rewilding project in the US. It ignited a rising ecological global consciousness, and the following decades witnessed a burst in rewilding research and projects – illustrating the importance of influencing hearts and minds as fuel for real change.

2000s: Trout in South London’s Wandle River

South London’s iconic Wandle River, a tributary of the Thames, was heavily used from Roman times through to the industrial revolution – its banks harboring factors and mills, the river having been purged of its natural features to canalize and speed up its flow. By 1805, the Wandle had grown into “the hardest worked river for its size in the world”, and its last trout was caught in 1934. The Wandle Trust was set up to clean out the river, redirect its flow, and restock it with fish. Today, even in proximity to large urban centers, trout, shrimp, and insects have blossomed once again. “Astonishingly in view of where it has come from – historically and geographically – it looks in places like the kind of chalk streams you would expect to find flowing through some of the most bucolic landscapes in England,” describes environmental journalist George Monbiot.

The rewilding of marine ecosystems is as crucial as that of terrestrial ecosystems. A movement has emerged to restore and rewild rivers and other bodies of water by removing barriers and dams, regulating fishing, and reintroducing and protecting wild species.

2007: Bison across Romania’s Southern Carpathian mountains

Centuries of overhunting throughout Romania’s Southern Carpathian mountains led to plummeting populations of European bison (or wisent), which entirely disappeared 200 years ago. Rewilding Europe and Romania’s World Wildlife Fund chapter have reacted with vigor. The first bison was released to the region in 2014, followed by yearly GPS collar-equipped bison reintroductions thereafter – the vision being to reestablish a demographically and genetically viable, thriving population. As a result of increased grazing, the region’s flora and fauna is flourishing. It now serves as a hub for scientific research, public education projects about local ecosystems, and programs empowering entrepreneurs to leverage the area’s emerging nature-based economy.

This initiative is nested within a larger rewilding initiative across Romania with the vision to create one of the largest wild areas in Europe, extending across 3 million hectares. Rewilding Romania is an example of rewilding in a manner which is both scalable and sustainable, exemplifying the socioeconomic sustainability of a nature-based economy – generating revenue and increasing the public’s awareness of Nature in a “cycle of accelerating beneficial growth to both humans and nature.

2017: Beavers throughout the United Kingdom

Nature’s charismatic architects, beavers have been dwarfed by human activity in the United Kingdom throughout the 20th century, resulting in increasingly frequent and erratic flooding. In 2008, the Wales Wild Land Foundation began a project to restore a 75-acre region of Welsh land, reforesting the area with broadleaf trees, followed by the reintroduction of the beaver in 2017. Remarkably, beavers have since truly metamorphosized wetlands by damming rivers, reducing flooding, and supporting more robust, complex ecosystems – home to thriving populations of otters, fish, water voles, various birds, and dragonflies.

Beaver rewilding is a quintessential example of the ripple effects of one keystone species on an entire ecosystem, as illustrated in the International Union for the Conservation of Nature (IUCN) Global Species Action Plan. In addition, the rewilding of wolves to Yellowstone served as a potent example of the potential of rewilding to not only restore an ecosystem, but an entire physical geography (including vegetation patterns and river banks), deeply interconnected with the species it is inhabited by.

2020s: Tasmanian devil, Australia

Australia’s fauna has been devastated by invasive predators introduced by European settlers, only recently exacerbated by forest fires killing nearly three billion animals; today, Australia retains the world’s highest mammal extinction rate. With a vision to rewild Australia, conservationists have looked to the Tasmanian devil. This apex predator, while keeping possum and wallaby populations in check, would drive out invasive foxes and cats, enabling native small mammals to recover. In parallel, it would enrich the soil, spread seeds, bury leaf litter, and minimize the buildup of flammable material – dampening the breadth of forest fires. Twenty-six healthy Tasmanian devils have been reintroduced to mainland Australia to date.

Rewilding the Tasmanian devil to Australia is a quintessential example of the positive feedforward impacts of rewilding: Reintroducing Tasmanian devils will limit one of the very factors that had been precipitating broad mammalian extinction in Australia, notably excessive forest fires. Nature, provided a little rebalancing, has its own, wise way of harmonizing itself through feedback loops embedded within broad floral and faunal life cycles.

2025+: The woolly mammoth and other species within Pleistocene Park, Northern Russia

Partly as a result of human overhunting, the end of the Pleistocene era 11,700 years ago saw a dramatic drop in global megafauna populations. The total mass of plants and animals in Siberia’s weakened tundra ecosystem is now 100 times less than at the time. By reintroducing large herbivores filling a vacant ecological niche, Pleistocene rewilding can mold the Arctic landscape back into the mammoth steppe it once was. A 62-square-mile Pleistocene Park was established in Northern Siberia to this end, having seen over the last two decades the step-wise reintroduction of bison, wild horses, musk oxen, reindeer, and goats – now hosting well over 150 such native animals. The end goal, however, is to rewild, to its Homeland, the woolly mammoth – essential engineer of this once vibrant Arctic ecosystem.

Scalable, economically viable, and aligned with the IUCN’s rewilding principles, Pleistocene rewilding is the most ambitious, pressing, and significant rewilding project on the planet to date.

An Optimistic Outlook on a Wild Future

A fundamental feature of humanity is not only our rather unique capacity for self-destruction – but our equally astonishing ability to imagine, collaborate, build and create. As a breakthrough conservation strategy, Rewilding has been met with tremendous promise and potential – harmoniously aligning with the European Union’s current conservation targets of species protection and ecosystem services while enabling carbon storage and sustainable recreation.

Most importantly, however, Rewilding is not simply a practical response to a global threat, it is a philosophy – addressing the question of how to live sustainably alongside and within nature. Rewilding has the capacity to weave back into the fabric of our lives the thrill, wonder, and enchantment so achingly devoid of our nature-deprived daily lives. At Colossal and around the world, let us continue to respond to this deep personal and planetary need, respect the wisdom of the Nature we ourselves were born from, and humbly contribute to the pressing and precious process of rewilding our Earth – neither exclusively for us nor for the planet, but for our harmonious and sustainable coexistence into the future. 


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