Fascinating new analysis by Yale professor suggests that protecting or expanding the populations of nine key groups of animals would remove huge amounts of carbon from the atmosphere - maybe even more than the combined efforts of forests, wetlands, and coastal and grassland ecosystems.
Climate change research has mostly concentrated on the importance of forests and seagrass meadows as the most efficient way of storing carbon. But bison, elephants, whales (see Whales: Important Carbon Sinks), sharks and other massive wild animals also store carbon in their bodies while promoting tree and seagrass growth, preventing carbon-releasing wildfires and packing down ice and soil to keep carbon in the ground, says Oswald Schmitz at Yale University.
“There’s been scepticism in the scientific community that animals matter, because if you just do the accounting, they’d say animals don’t make up much of the carbon on the planet, so they can’t be important,” he says. “What we’re doing is connecting the dots, showing that animals – despite their lack of abundance – have an outsized role, because of the multiplier effects that they create.”
To keep the average global temperature from rising more than 1.5°C above its pre-industrial level, scientists estimate that we need to remove 6.5bn tonnes of CO2 per year from the atmosphere until 2100, reports New Scientist. Current models that focus on protecting and restoring forest, wetland, coastal and grassland ecosystems would fall short by an estimated 0.5 to 1.5 billion tonnes per year, says Schmitz. Whilst it's hoped that various forms of direct air carbon capture will help make up the difference - and they are experiencing meteoric growth - these technologies are yet to be scaled up to provide a meaningful difference. So, Schmitz argues, the world should look to animals to help us in the climate fight.
He and his colleagues reviewed data from previous publications about the environmental effects – including dispersing seeds, trampling, carbon cycling, feeding behaviour, hunting behaviour and methane production – of dozens of kinds of wild animals.
They determined that we could theoretically meet the planet’s carbon reduction goals by protecting six groups of animals and expanding another three. The populations of reef sharks, grey wolves, wildebeest, sea otters, musk oxen and ocean fish need to be maintained at current levels. We would also need populations of at least 500,000 African forest elephants, 2 million American bison and 188,000 baleen whales in the Southern Ocean. Collectively, these populations could help capture approximately 6.41bn tonnes of carbon dioxide annually, says Schmitz.