Researchers at the University of Sussex have forwarded a unique new method for addressing climate change called rewilding.
Rewilding involves strategically reintroducing certain species of animal into areas where their populations have been diminished or eliminated entirely.
Changing animal populations can have significant effect on the amounts of greenhouse gas being absorbed by plant life, and if done right could play a positive role in lessening the impact of climate change.
‘The key thing to remember here is that nature is complex and needs to be complex,’ University of Sussex lecturer Chris Sandom told Phys.org.
The key concept is creating a balance between herbivores and predators to ensure neither have an outsized effect on the environment.
In one example, researchers point to regions in North American and Europe where the absence of predators like wolves has led to unchecked deer population growth.
Deers feed on a variety of plant leaves that would otherwise play an important role in absorbing greenhouse gases from the environment.
At the same time large herbivores like deers and cows can further add to the production of greenhouse gases like methane through their own bodily waste.
The key, according to scientists, is finding the right balance for each environment by selectively introducing a carefully chosen mix of species to restore balance to an environment.
‘Past extinctions mean only a small fraction of the species present in North and South America, Europe, and Australia can be reintroduced to rewilding projects,’ University of Sussex’s Owen Middleton said.
‘If all the species available were reintroduced in these places, predators are likely to exert more control on herbivores than in the past. This would likely result in more trees growing with climate change mitigation benefits.’
‘In Africa and Asia where extinction was less severe the megaherbivores would likely be more dominant. In savannahs this could stop trees growing, reducing climate mitigation potential but would be important for biodiversity. Regional analysis is needed to explore the details.’
‘But these are simple estimations of a complex system. Future research should focus on regional case studies which includes social and ecological feasibility of reintroducing species, as well as how it could assist with the climate and other emergencies.’