As the world is struggling to find climate solutions to curb the impact of global warming, an overlooked climate change solution was suggested by a new report published in the journal Nature Climate Change, known as trophic rewilding. Rewilding refers to the restoration of the functional roles of animals in ecosystems, which can be a potential climate solution. The report claims that rewilding just nine wildlife species or groups, including African forest elephants, American bison, fish, gray wolves, musk oxen, sea otters, sharks, whales, and wildebeest would contribute more than 95% towards the global target of extracting 500 billion metric tons of carbon dioxide from the atmosphere by 2100, helping cap the global temperature rise at less than 1.5C below pre-industrial levels, as called for in the Paris Agreement.
Animals have a profound effect on the effectiveness of carbon sinks, like plants and soil. They help plants grow and store more carbon, and even prevent wildfires. Animals can also keep carbon in the soil and sediment by changing how microbes and chemicals work in these systems. For example, an experimental study conducted in a tropical forest in Guyana found that tree and soil carbon storage increased by four to five times, as the number of mammal species increased from five to 35. However, as human activities, including livestock agriculture, extractive industries, infrastructure development, and poaching, are encroaching on natural habitats, animals are increasingly unable to fulfil their roles in ecosystems. Currently, natural climate solutions focus primarily on protecting and restoring ecosystems like forests and grasslands, overlooking the role that animals play in supplying nutrients, reducing fire risks, and helping plants grow.
The report suggests that to successfully reintroduce wildlife into areas where humans live, it's important to work closely with communities to address the complex social issues that threaten the natural habitat. The conservation of wildlife, allowing species to play their functional roles in ecosystems, offers untapped potential as a solution to climate change.
"There's a huge untapped potential to consider conserving wild animals as a climate solution," said report lead author Oswald Schmitz, a professor at the Yale School of the Environment.
"If you do some of the rough calculations, the numbers rival those of what the IPCC [Intergovernmental Panel on Climate Change] is right now promoting in terms of converting everything to solar or wind generation… the numbers are in the same ballpark."
The Sustainable Development Goals (SDGs) of the United Nations aim to create a better world for all by 2030. The SDGs have 17 goals, and the 15th one is Life on Land. The goal is to protect, restore, and promote the sustainable use of terrestrial ecosystems, sustainably manage forests, combat desertification, halt and reverse land degradation, and halt biodiversity loss. Trophic rewilding is an overlooked climate change solution that aligns with the vision of a global society by promoting conservation of wildlife and protecting biodiversity. Thus, trophic rewilding can be considered an essential component of achieving SDG 15.