Rewilding & Habitat Restoration (HL) (DP IB Environmental Systems & Societies (ESS)): Revision Note

Rewilding & habitat restoration

What is rewilding?

• Rewilding is a conservation method that involves:

  • Allowing habitats to return to their natural state

  • Reintroducing species that were previously driven out or became extinct in that area

  • Allowing ecosystems to self-regulate

  • Promoting natural processes such as predation, grazing, and habitat regeneration

  • Minimal human management

What is habitat restoration?

• Habitat restoration aims to:

  • Repair and regenerate damaged ecosystems, often through human intervention and control

  • Bring back lost biodiversity and restore ecosystem functions

  • Use strategies such as replanting native species, removing invasive species, or rehabilitating degraded landscapes (e.g. polluted rivers or deforested areas)

Positive feedback loops in rewilding and habitat restoration

• Positive feedback loops refer to a process where the results of an action amplify that action over time

  • In conservation, some positive feedback loops can lead to enhanced ecosystem recovery

• Rewilding and habitat restoration can trigger positive feedback loops that:

  • Enhance biodiversity: For example, when predators are reintroduced (e.g. wolves in Yellowstone National Park), they control herbivore populations, allowing vegetation to recover and creating valuable habitats for other species

  • Promote ecosystem equilibrium: The recovery of ecosystems through natural processes leads to healthier, more balanced ecosystems where species interact naturally

• Examples of positive feedback:

  • Increased growth and biomass: As vegetation recovers, it supports herbivores and pollinators, which in turn feed predators

    • This sustains the ecosystem

  • Enhanced reproduction and survival: A restored habitat can increase the survival rates of species, which then leads to more reproduction

    • This further stabilises food webs

Benefits and limitations of rewilding

Benefits of rewilding

• Restores biodiversity: Rewilding brings back species that play important roles in ecosystems, leading to healthier environments

• Improves ecosystem services: Rewilded areas can provide important services (that are also beneficial to human societies) like carbon sequestration, flood prevention, and water purification

• Promotes sustainable ecotourism: Rewilded areas often become destinations for wildlife enthusiasts, providing economic opportunities to local communities

Limitations of rewilding

• Land-use conflict: There is often competition between using land for food production and allocating it for rewilding, especially in countries where land is scarce and farming is vital for the economy

  • Balancing agriculture with conservation can be difficult, especially in densely populated or economically poor regions

• Unintended consequences: Sometimes reintroduced species may cause unforeseen effects on local ecosystems or human populations

  • For example, reintroduced predators may pose risks to livestock

• Economic growth vs. conservation: In some regions, governments prioritise economic activities (e.g., mining, logging) over conservation

  • This can stop large-scale rewilding projects from being undertaken

Examples of rewilding projects

Knepp Estate, England

• Knepp Estate is one of the most well-known rewilding projects in the UK, located in West Sussex

• Formerly an intensively farmed estate, Knepp turned to rewilding in 2001 when the land proved unproductive for conventional agriculture

• Instead of farming, the estate focused on allowing nature to take over, encouraging natural processes such as free-roaming grazing

• Benefits:

  • Increased biodiversity: The introduction of grazing animals like longhorn cattle, Tamworth pigs, and Exmoor ponies has transformed the landscape

    • This has led to the return of rare species like nightingales, turtle doves, and purple emperor butterflies

  • Natural ecosystem regeneration: With less human intervention, the land has regenerated naturally, increasing the variety of habitats, including wetlands, scrublands, and woodlands

  • Carbon sequestration: The increase in natural vegetation, especially woodlands, has helped sequester more carbon, contributing to climate change mitigation

• Limitations:

  • Land-use conflict: Some have questioned the rewilding approach in Knepp, particularly the decision to move away from farming

    • Given the pressure to use land for food production, this raises debates about balancing agriculture and conservation in the UK

  • Economic viability: Although the project has seen biodiversity benefits, it depends on ecotourism and government grants for financial sustainability

    • This raises questions about its long-term economic viability without external support

Affric Highlands, Scotland

• The Affric Highlands project is one of Scotland’s largest rewilding efforts, aiming to restore natural habitats across 500,000 acres

• It focuses on:

  • Reviving native forests and peatlands, important carbon sinks

  • Bringing back wildlife that was once common in the region

• Benefits:

  • Restoration of native species: Efforts are being made to reintroduce species like red squirrels, wildcats, and potentially lynx

    • These species play important roles in the ecosystem

  • Ecosystem services: Restoring peatlands and forests not only improves biodiversity but also provides important ecosystem services such as water purification, flood regulation, and carbon storage

  • Cultural revival: Local communities, especially in the Highlands, benefit from increased tourism and ecotourism opportunities

• Limitations:

  • Rewilding vs. rural development: Some local communities are concerned that large-scale rewilding could impact agricultural activities or rural development

  • Reintroduction challenges: Reintroducing top predators like the lynx faces opposition from farmers concerned about livestock predation

Oostvaardersplassen, Netherlands

• Oostvaardersplassen is a unique rewilding project in the Netherlands, situated on reclaimed land that was originally planned for industrial development

• Instead, it became a nature reserve where large herbivores such as red deer, Konik horses, and Heck cattle were introduced to allow natural grazing to shape the landscape

• Benefits:

  • Landscape restoration: The introduction of these large grazers helped create a mosaic of habitats, including grasslands, wetlands, and scrub

    • This has allowed for the growth of various plant species and the return of birds like white-tailed eagles and spoonbills

  • Natural processes: The project demonstrated how rewilding could mimic natural processes without active human management

• Limitations:

  • Harsh winters: The reserve has faced criticism for its hands-off approach, particularly during harsh winters when many herbivores starved due to lack of food

    • This has led to debates about whether human intervention is needed in these extreme circumstances

  • Management dilemmas: The lack of predators to naturally control herbivore populations has resulted in overgrazing and population booms

    • This has raised questions about whether the ecosystem can remain self-sustaining

Gorongosa National Park, Mozambique

• Early in the 2000s, Gorongosa National Park underwent a significant restoration effort after suffering decades of civil war

• Many species were driven to local extinction due to hunting and habitat destruction

• Since the restoration project began, efforts have been made to restore biodiversity and rebuild local ecosystems

• Benefits:

  • Restocking of key species: Iconic species like elephants, lions, hippos, and buffalo were reintroduced, helping to restore the park’s ecosystem dynamics

    • This has created a more balanced food web and restored natural predator-prey interactions

  • Community involvement: The park restoration has also brought significant benefits to local communities through job creation, ecotourism, and education programmes

    • The park is now seen as a symbol of Mozambique’s recovery

  • Biodiversity recovery: Gorongosa is becoming a biodiversity hotspot again

    • Research has shown an increase in both animal and plant species

• Limitations:

  • Human-wildlife conflict: As large predators and herbivores are reintroduced, there is potential for conflict with local communities, particularly farmers

    • Managing this balance is an ongoing challenge

  • Funding dependency: Long-term success depends on sustained funding and continued collaboration between government agencies, NGOs, and international partners to support both conservation work and local livelihoods