International Rewilding Day: Rewilding at Kraansvlak

Today, on International Rewilding Day, students from Sheffield Hallam University (Geography and Environmental Science) have travelled to the Kraansvlak sand dunes just west of Amsterdam. This remarkable project focuses on rewilding an important but degraded landscape by reintroducing European bison, the largest extant land mammal in Europe.

Spot the Bison! Kraansvlak sand dunes, the Netherlands

The aim of the project is to restore natural processes to the sand dunes and promote biodiversity.  The project is part of a wider European programme aimed to bring bison back from the brink. The return of the bison stands as one of Europe’s most inspiring wildlife recovery stories and demonstrates how they can also help restore missing ecological functions. At a time of rapid biodiversity decline, the initiative provides both scientific knowledge and a hopeful narrative of recovery for other work to build upon.

Rewilding: A Rising Movement

Rewilding has garnered considerable attention in recent years, representing a fundamental shift in our approach to nature conservation. Unlike past conservation efforts that focused on managing habitats and species based on fixed ideas of what nature should resemble, rewilding prioritises restoring ecosystem functions; allowing natural processes to flourish, and reintroducing keystone species. It involves re-thinking our relationship with the non-human world, relinquishing control to allow nature more space and autonomy to thrive.

Rewilding in the Netherlands

The rewilding movement originated in North America in the 1990s with a focus on restoring large core areas and reintroducing carnivores like grey wolves to Yellowstone National Park. However, rewilding also gained momentum in the Netherlands around the same time. As one of Europe's most densely populated countries with limited natural areas, the Dutch rewilding movement emphasised the role of large grazing animals built on the work of Frans Vera and his colleagues. They recognised the importance of species like aurochs (an extinct wild cattle species), elk, wild boar, and tarpan (an extinct European wild horse) in creating biodiverse mosaic landscapes. Through direct impacts such as creating irregular patterns of consumption, dispersing seeds, transferring nutrients, and physical disturbance through grazing, browsing and trampling, these animals contribute to the continuous formation of dynamic and varied ecosystems.

Bison: Europe’s Mighty Giants

The largest land mammal that exists today in Europe is the European bison (Bison bonasus) with a population that is recovering rapidly. But the fate of this animal could have been very different. Once widespread across the continent, by the early 20th century, European bison were at the edge of extinction due to a combination of habitat loss and hunting.   In 1927, the last wild European bison was shot in the Caucasus, leaving fewer than 60 individuals in captivity. Reintroduction efforts began in the 1950s, and today, free-ranging herds roam in several European countries, including Germany, Switzerland, Poland, Belarus, and Lithuania. The Białowieża Primeval Forest hosts the largest free-living population, with around 1000 wild bison. Over the past decade, their numbers have surged from over 2500 to about 10,000 individuals, marking a remarkable recovery.

Shifting Baselines and Ecological Recovery

But the reintroduction of European bison to Kraansvlak is different from other projects across the continent and interesting for a number of reasons. For a long time, ecologists believed European bison were woodland animals – (they are sometimes referred to as the European wood bison) but perhaps this was based on a jaded interpretation of their needs and the fact that they had long been missing from other habitats – an example of Shifting baseline syndrome. Shifting baseline syndrome is a concept that describes a gradual change in the accepted norms of what constitutes an appropriate condition for nature.  When nature is declining over generations, people’s perceptions of what constitutes a thriving natural system or an “optimal” habitat for species subtly shifts. We become accustomed to the status quo—the conditions we witness during our lifetime. And therein lies the danger: our baseline shifts, and we inadvertently narrow our view. We might not fully understand where species can thrive, and we might not be protecting their optimal habitat. There are some great examples at the Knepp Estate, a former farm that has been rewilded in England.  For instance, the iconic nightingale was considered a woodland species – but is highly abundant within the scrub that has established within this rewilding project at Knepp – defying what the text books say is this species optimal habitat. 

The 10,000 European bison that exist in Europe today are often given supplementary feed by rangers to avoid them spreading out of the woodlands into other areas of land (such as neighbouring agricultural land). Yet the work at Kraansvlak has demonstrated that the small herd living within the 300 hectares of dunes can flourish without additional feeding and roam with very minimal human interventions – they might prefer a more open habitat.

Rewilding as Experimenting with Nature

A small herd of bison was introduced to Kraansvlak in 2007 as an experimental initiative by the water company PWN, which oversees the management of the dunes. These bison marked the first of their kind in the Netherlands since their extinction. The primary goal was to combat encroaching grasses and shrubbery that were adversely affecting the area's wildlife and the dynamic functioning of the sand dune system.

Subsequent studies on the site have shown the positive impact bison can have on biodiversity in these environments. Bison, alongside other grazing animals, play a pivotal role in rejuvenating natural processes within the sand dunes. By disrupting vegetation, they create expanses of bare sand. Wind action then expands these areas through the process of blowouts, further transporting sediments across the dune. This open sand provides critical habitats for insects and vertebrates, which, in turn, serve as vital food sources for numerous bird species. Thus, European bison emerge as keystone species within sand dune habitats, exerting a disproportionately significant influence on their surroundings relative to their population size.

Their success in Europe's most densely populated country demonstrates their ability to prosper in close proximity to humans and highly modified ecosystems. As Sara Matthée a Rewilding Intern at PWN explains

“ Kraansvlak shows that in an urban densely populated area such a rewilding project is possible. If you can do it here, you can do it in so many other places”

Rewilding the urban landscape

Whilst bison are not ideal urban inhabitants, the concept of rewilding is becoming increasingly relevant in the quest to make our cities more environmentally sustainable. Urban green and blue spaces provide vital habitats and corridors that allow wildlife to thrive within and safely pass through cities. Welcoming a greater variety of wildlife into our cities can be challenging for a number of reasons, urban green spaces have traditionally been very intensively managed and manicured and leaving areas to ‘go wild’ make them look neglected and less inviting to people. Wild animals in cities have often been classified as problematic ‘vermin’, seen as unhygienic, destructive and even dangerous. These cultural challenges are important, but we would argue that the biodiversity and climate crises make these barriers worth overcoming. Wilder urban landscapes help us to adapt to changing climates as well as mitigating against future harm. We humans get the opportunity to live alongside a wider variety and quantity of non-human species which can improve our connection to nature making us calmer, happier and more likely to live more environmentally sustainable lives.

Simone de Maat the ranger from PWN shared these thoughts when reflecting on our trip today:

“Excursions such as these are important to really feel that humans are part of nature and show how to interact with large grazing animals”.

Our students today, and those enrolled in our new Climate Sustainability and Environmental Management (BSc) course, will play a pivotal role in advancing these concepts. They will actively contribute to future rewilding initiatives, utilising a blend of environmental and social sciences to address the challenges ahead.