Trophic rewilding can expand natural climate solutions
New scientific evidence showing that protecting and restoring wild animals and their functional roles can enhance natural carbon capture and storage, enhancing the ability to prevent climate warming beyond 1.5 °C.
Study link: Nature Climate Change (2023)
Natural climate solutions are being advanced to arrest climate warming by protecting and enhancing carbon capture and storage in plants, soils and sediments in ecosystems. These solutions are viewed as having the ancillary benefit of protecting habitats and landscapes to conserve animal species diversity. However, this reasoning undervalues the role animals play in controlling the carbon cycle.
This study presents scientific evidence showing that protecting and restoring wild animals and their functional roles can enhance natural carbon capture and storage. This calls for new thinking that includes the restoration and conservation of wild animals and their ecosystem roles as a key component of natural climate solutions that can enhance the ability to prevent climate warming beyond 1.5 °C.
Wild animals contain only 0.3% of carbon held in biomass globally. However, synthesis of 163 experimental studies shows that many could nonetheless exert outsized control by causing 15% - 250% differences in amounts of carbon in plants, and soils and sediments, relative to conditions where they are absent. Animal functional controls come from foraging and movements that redistribute seeds and nutrients across landscapes and seascapes, and trampling, burrowing, wallowing, and ecosystem engineering which causes soil and sediment disturbance.
These various functions enhance the diversity, abundance and carbon density of plant communities, change fire regimes in ways that stimulate carbon capture and storage, prevent massive CH4 release by protecting against permafrost thawing, enhance soil and sediment carbon stocks via organic matter (fecal, carcass, vegetation) deposition, and improve soil and sediment carbon retention by influencing microbial processes and chemical reactions.
Lead researcher: Oswald Schmitz, Yale University (Yale U)
Contributing researchers: Magnus Sylvén (Global Rewilding Alliance), Trisha Atwood (Utah State U), Elisabeth Bakker (Netherlands Inst. Ecology), Fabio Berzaghi (Global Ocean Inst.), Jedediah Brodie (U Montana), Joris Cromsigt (Swedish U Agricultural Sciences), Andrew Davies (Harvard U), Shawn Leroux (Memorial U Newfoundland), Frans Schepers (Rewilding Europe), Felisa Smith (U New Mexico), Sari Stark (Arctic Centre), Jens-Christian Svenning (ECONOVO), Andrew Tilker (ReWild), Henni Ylänne (U E. Finland)