What the best evidence shows: rewilding can boost soil, plants, and animals
The strongest direct test of rewilding on degraded land comes from a 2025 controlled experiment on rangelands. After two years, sites where researchers reintroduced native herbivores, carnivores, and plants had 40–60% more vegetation cover than untreated control sites (p < 0.05). Soil quality also improved: organic carbon reached 2.3% and nitrogen 0.18%, versus 1.5% and 0.12% in controls (p < 0.05) [1]. Species diversity, measured by the Shannon-Weiner Index, rose from 2.8 to 3.5 (p < 0.01) [1]. These numbers mean that in this setting, rewilding clearly restored basic ecosystem functions like plant growth and nutrient cycling within a short time.
A separate 2023 study on soil-disturbing vertebrates—animals like burrowing mammals that turn over soil—found that reintroducing them improved soil composition and function (e.g., nutrient cycling) across multiple ecosystems, though effects on physical structure (like soil stability) were weaker [6]. The authors argue that these animals can be more effective than mechanical soil treatments because they create self-sustaining, heterogeneous disturbances [6]. So when rewilding targets the right animals, it can directly repair degraded soils.
Where rewilding falls short: not all disturbances are equal, and not all rewilding is the same
A 2025 global meta-analysis of 42 case studies (305 observations) found that rewilding increased ecosystem resilience in about 70% of cases, but the success rate dropped for abiotic disturbances like drought and fire [2]. In other words, rewilding is better at helping ecosystems resist invasions by non-native species (biotic disturbances) than at buffering them against climate-driven stressors. The same analysis showed that interventions targeting only trophic complexity—just adding large animals—did little for biodiversity on their own; the best results came when rewilding also restored natural disturbance patterns (e.g., allowing some fires or floods) and improved connectivity between habitats [2].
A 2023 study comparing passive rewilding (letting nature take its course) with trophic rewilding (actively reintroducing large herbivores) in English farmland found that the added benefits of trophic rewilding were not always clear-cut [4]. The authors note that few empirical studies have rigorously tested whether reintroducing large animals actually boosts biodiversity and ecosystem functioning beyond what passive recovery achieves [4]. This means that in some landscapes, simply removing human pressure may be as effective—or more cost-effective—than active reintroductions.
The practical catch: rewilding needs space, time, and careful targeting
Even when rewilding works ecologically, it may conflict with other land uses. A 2024 land-use modeling study for Great Britain projected that by 2080, only 5,000–7,000 km² would be available for rewilding without compromising ecosystem services like food production [3]. An additional 24,000–42,000 km² of upland grazing land could be converted, but none of these areas reliably overlapped with priority conservation habitats like peatlands or ancient woodlands [3]. So the places most in need of restoration may be the hardest to rewild without trade-offs.
Long-term monitoring is also scarce. The 2025 rangeland study lasted only two years, and the authors caution that long-term effects remain unknown [1]. A 2025 review of rewilding in degraded ecosystems emphasizes that socio-economic barriers—like local resistance and funding gaps—often derail projects, and that adaptive management over decades is essential [5]. Without sustained commitment, early gains in vegetation or soil can be lost.
Sources used in this answer
Trophic Rewilding Outcomes on Ecosystem Function and Biodiversity in Degraded Rangelands
Trophic rewilding in degraded rangelands increased vegetation cover by 40–60%, soil organic carbon to 2.3% (vs. 1.5% in controls), and species diversity (Shannon index 3.5 vs. 2.8) after two years [1].
Quantifying the impacts of rewilding on ecosystem resilience to disturbances: A global meta-analysis.
A global meta-analysis of 42 case studies found rewilding improved ecosystem resilience in ~70% of observations, but success was lower for abiotic disturbances like drought and fire [2].
An assessment of future rewilding potential in the United Kingdom
Land-use modeling for Great Britain projected only 5,000–7,000 km² available for rewilding by 2080 without conflicting with ecosystem services, and these areas rarely overlapped with priority conservation habitats [3].
Trade-offs between passive and trophic rewilding for biodiversity and ecosystem functioning
Trophic rewilding in English farmland did not consistently provide additional biodiversity or ecosystem-function benefits beyond passive rewilding, highlighting a need for more empirical tests [4].
Exploring the Role of Rewilding in Enhancing Ecosystem Services and Biodiversity Restoration in Degraded Ecosystems
A review of rewilding in degraded ecosystems concluded it can restore natural processes and improve water management, carbon capture, and soil fertility, but is hampered by funding gaps and local resistance [7].
Rewilding soil-disturbing vertebrates to rehabilitate degraded landscapes: benefits and risks
Reintroducing soil-disturbing vertebrates (e.g., burrowing mammals) improved soil composition and function across ecosystems, with advantages over mechanical soil treatments in creating self-sustaining disturbances [8].