IB Environmental systems and societies 3.3E Rewilding Projects Notes

Rewilding Can Push a Degraded Ecosystem Into a New Stable State

1. A positive feedback loop occurs when an initial gain in biodiversity or habitat quality produces further ecological gains that reinforce recovery.
2. Rewilding and habitat restoration start these loops by boosting growth, biomass, reproduction, and survival, which strengthens food webs and stability.
3. Sustained over time, these loops can flip a degraded ecosystem into a self-sustaining, biodiverse alternative stable state.

The Feedback Mechanisms That Reinforce Recovery

1. Greater plant biomass improves soil quality, moisture retention, and microclimates as native vegetation returns.
2. Higher biodiversity makes the ecosystem more resilient to disturbances such as drought and disease.
3. Reintroduced keystone predators regulate herbivore numbers, preventing overgrazing and letting plants recover.
4. Better food and habitat raise reproduction and survival, creating self-sustaining populations.
5. Stable predator-prey interactions keep nutrient cycling and energy flow balanced.
6. Recovered ecosystems store more carbon, regulate temperature, and retain water, building climate resilience.

Rewilding Delivers Real Gains for Nature and People

1. Biodiversity recovery: habitat restoration lets native plants and animals thrive.
2. Ecosystem services: rewilded landscapes store carbon, regulate water cycles, and prevent soil erosion.
3. Ecotourism income: rewilded areas attract tourism and conservation funding, providing alternative livelihoods.
4. Keystone reintroduction: restoring species such as wolves, lynx, and bison rebuilds trophic cascades and ecosystem balance.

But Rewilding Creates Land-Use Trade-Offs

1. Competition with agriculture: converting farmland to rewilded land can reduce food production and raise food-security concerns.
2. Economic uncertainty: landowners may lose agricultural subsidies when they switch to conservation land use.
3. Human-wildlife conflict: reintroduced predators such as wolves and lynx can prey on livestock.
4. Social resistance: local communities may oppose land-use changes that threaten traditional livelihoods.
5. High initial costs: projects need significant investment in land purchase and species monitoring.

Case Studies: Knepp Estate and the Affric Highlands

Knepp Estate, England

1. The Knepp Estate was a conventional farm that switched to rewilding in the early 2000s.
2. Free-roaming cattle, ponies, deer, and pigs were introduced to mimic natural grazing.
3. Rare species returned, including nightingales, purple emperor butterflies, and white storks.
4. Ecotourism and regenerative agriculture now provide sustainable income.
5. Critics note the model is hard to scale, since converting farmland is not feasible everywhere.

Affric Highlands, Scotland

1. The Affric Highlands project aims to restore native forests, peatlands, and river systems in the Scottish Highlands.
2. It supports species reintroductions such as beavers and red squirrels and improves habitat connectivity.
3. Land-use tensions arise between forestry, sheep farming, and conservation.
4. The project emphasizes community involvement so local livelihoods are protected.
5. It also integrates carbon sequestration goals, making it a climate-focused conservation effort.

Assessing Rewilding Success With Data

1. Secondary data from biodiversity databases tracks species recovery, habitat regeneration, and carbon storage.
2. Remote sensing and GIS mapping show changes in vegetation cover and land use over time.
3. Questionnaires and surveys measure public perception, ecotourism impact, and local support.
4. Comparing pre- and post-rewilding biodiversity surveys shows whether conservation goals are being met.
5. Economic assessments of tourism revenue and jobs reveal the financial viability of a project.