Study: 25% of Europe Could Be Rewilded

Europe, a densely populated continent, has seen much of its natural areas profoundly shaped by centuries of human activity. Agriculture, urbanization, and industrialization have transformed its landscapes, from the dense forests of Scandinavia to the open plains of Eastern Europe. 

A loss of habitat across Europe

A reported released in 2021 by the European Union’s Joint Research Centre found that only 3% of the EU’s total forested area is old growth forest. These mature forests are largely undisturbed by human activities but are highly fragmented across Europe. Old growth forest are also important as vital habitats for biodiversity and help play a crucial role in carbon sequestration and climate regulation. Yet less than 1.2% of the total area of the European Union is made up of old growth forests.

Wetlands are another exampled of habitat in Europe that has experienced severe loss over the centuries. Despite the long coastline that borders the continent on three sides, only about 20% of wetlands still remain.

The loss of natural habitat in Europe has also had an impact on biodiversity as more areas become affected by human activities such as deforestation, agriculture, and development.

Rewilding: A passive strategy for restoring ecological health in Europe

Rewilding is a key strategy for enhancing ecological health and strengthening biodiversity in Europe.

What is rewilding? Rewilding focuses on allowing ecosystems to regenerate with minimal human intervention. Unlike traditional conservation, which often involves intensive management and human intervention, rewilding emphasizes the importance of allowing nature to take its course with m

The difference between passive and active rewilding lies in the approach taken to restore ecosystems and allow nature to recover.

Passive Rewilding

Passive rewilding focuses on minimal human intervention. It involves allowing nature to take its course, with the idea that ecosystems will gradually restore themselves if left undisturbed. This approach may involve actions such as removing barriers to natural processes (e.g., stopping agricultural practices or halting deforestation) and then stepping back to let the ecosystem recover on its own.

The goal with passive rewilding is that, over time, natural succession and processes like seed dispersal, natural regeneration of plants, and wildlife recolonization will lead to the restoration of a balanced ecosystem. Passive rewilding is often seen as a more cost-effective and less labor-intensive approach but may take longer to see significant ecological changes.

Active Rewilding

Active rewilding, on the other hand, involves at least some direct human intervention to speed up or guide the recovery of ecosystems. This might include activities such as reintroducing native species that have been extirpated (locally extinct), actively restoring habitats (e.g., planting trees, creating wetlands), removing invasive species, or implementing measures to restore natural processes like grazing or fire regimes.

Active rewilding is often necessary in landscapes that have been heavily modified by human activity and where natural recovery would be too slow or unlikely without assistance. This approach is more resource-intensive but can lead to quicker and more predictable outcomes.

How much of Europe could be rewilded?

Research published in the journal Current Biology looked at rewilding opportunities in Europe. Led by a researcher from Spain’s National Museum of Natural Sciences, the study mapped out the potential for rewilding across Europe.

To select areas for rewilding in Europe, researchers followed a four-step process.

• First, they identified regions with minimal human impact using a grid system, focusing on areas where human activities were least present.
• Next, they grouped these low-impact areas into clusters based on size, categorizing them into different types of rewilding ecosystems depending on their ability to support key species like large carnivores and herbivores.
• The third step involved mapping the distribution of these key species to determine whether an area was suitable for passive or active rewilding.
• Finally, they used a conservation planning tool to assess how well these areas could help countries meet their conservation goals, particularly in terms of expanding protected areas with balanced ecosystems.

The study calculated that approximately 117 million hectares, or about one-quarter of the continent, is suitable for rewilding initiatives. The two main types of rewilding opportunities: passive and active, are each associated with different geographical regions and climatic conditions.

Why is rewilding important in Europe?

In Europe, rewilding efforts are particularly significant because of the continent’s long history of intensive land use. Many European landscapes have been heavily modified for agriculture, urban development, and industry, leading to the loss of natural habitats and the extinction or decline of many species. Rewilding seeks to reverse this trend by restoring these landscapes, where available, to a more natural state.

Suitable areas for rewilding

The research found that 70% of the identified rewilding areas are located in cooler climates, primarily in regions like Scandinavia, the Scottish Highlands, and the Iberian Peninsula. These areas, characterized by minimal human disturbance and the presence of key mammal species, are ideal candidates for passive rewilding.

Active rewilding such as reintroducing species that have been lost, is more widely distributed across Europe. Regions identified for active rewilding include Corsica, Sardinia, southern France, and parts of the Netherlands, Denmark, Sweden, and Norway. 

Key European geographical regions of rewilding

1. Mountainous areas

Mountain regions, such as the Alps, the Carpathians, and the Pyrenees, are prime locations for rewilding efforts. These areas, often less densely populated and with large expanses of natural habitat, offer opportunities for the reintroduction of larger species like wolves, lynxes, and bears. The rugged terrain and lower human presence in these regions create ideal conditions for these apex predators, which play a crucial role in maintaining the balance of ecosystems.

For example, the rewilding efforts in the Southern Carpathians are focused on protecting these large carnivores and restoring the forests they depend on. This not only enhances biodiversity but also contributes to the stabilization of the landscape, preventing soil erosion and maintaining water quality.

2. Riverine and wetland regions

Europe’s rivers and wetlands have been heavily modified for agriculture, urban development, and flood control, leading to significant ecological degradation. Rewilding in these areas involves restoring the natural flow of rivers by removing dams, re-establishing wetlands, and reintroducing species such as beavers, which are natural engineers of wetland ecosystems.

The Danube Delta, one of Europe’s largest and most biodiverse wetland areas, is a key site for rewilding. Efforts here focus on reviving the natural hydrology of the region, which supports a wide variety of plant and animal species. The restoration of these wetlands is also crucial for flood mitigation and water purification, highlighting the importance of rewilding for human communities as well.

3. Forests and woodlands

Forested areas, especially those that have been cleared for agriculture or timber, are another focus of rewilding efforts. In regions like the Scottish Highlands, rewilding involves reforesting large areas with native tree species and allowing natural processes, such as the spread of seeds by animals, to take over. This helps to restore the natural structure and function of these ecosystems, providing habitat for a wide range of species.

The expansion of forests also plays a role in carbon sequestration, which is critical in the fight against climate change. By allowing forests to regenerate naturally, rewilding projects contribute to the long-term stability of Europe’s climate and biodiversity.

The need for rewilding as a conservation strategy in Europe

By identifying and prioritizing areas with high rewilding potential, a significant part of Europe can better allocate resources to expand protected areas and restore ecosystems.  By converting abandoned land back to a more natural state through rewilding, these conservation efforts also can help European Union countries meet European Biodiversity Strategy for 2030 goals.

The study

Araújo, M. B., & Alagador, D. (2024). Expanding European protected areas through rewilding. Current Biology. DOI: 10.1016/j.cub.2024.07.045.

Fonte : National Geographic