A Single Herd of Bison Can Help Capture CO2 From Over 40,000 Cars, Scientists Find

Bison-tennial

In 2014, a rewilding project reintroduced European bison into the foothills of the Tarcu mountains in Romania, where they hadn't been seen for over two centuries.

Now, a decade later, we're beginning to observe the remarkable ways this has transformed the region's ecology — offering a glimmer of hope in our efforts to combat climate change.

As detailed in a yet-to-be-peer-reviewed study, researchers found that the bison herd, which now numbers 170, appears to be taking some 54,000 tons of carbon out of the atmosphere every year.

That's the equivalent of the CO2 emissions of 43,000 American cars over the same time period, The Guardian reports — and nearly ten times the amount of carbon captured by the region before the bison were reintroduced. The work adds to a growing body of evidence on how animals can play a crucial role in reducing the greenhouse gases in our atmosphere that are heating our planet — as opposed to more technological methods.

Mammal-Mia!

Bovines can get a bad rep when it comes to the climate; cows are infamous for belching tons of methane, another greenhouse gas. But by and large, those cows are in a farm environment, living and feeding in unnatural ways.

In the wild, it's a different story. As ruminants, bison play a key role in maintaining an ecosystem's diversity of plant life. And plants — not to mention the soil they furnish — are the real heavy lifters when it comes vacuuming up carbon.

"Bison influence grassland and forest ecosystems by grazing grasslands evenly, recycling nutrients to fertilize the soil and all of its life, dispersing seeds to enrich the ecosystem, and compacting the soil to prevent stored carbon from being released," study lead author Oswald Schmitz of the Yale School of the Environment told The Guardian.

"These creatures evolved for millions of years with grassland and forest ecosystems, and their removal, especially where grasslands have been ploughed up, has led to the release of vast amounts of carbon," he explained. "Restoring these ecosystems can bring back balance, and 'rewilded' bison are some of the climate heroes that can help achieve this."

This is a refreshing perspective. Often, efforts to offset carbon emissions are obsessed with planting trees — perhaps detrimentally so. But if this study’s anything to go by — it's worth reiterating it's awaiting peer-review — we should be paying more attention to the role that other forms of wildlife play, too.

"This study reinforces an emerging consensus that large mammals have very important roles in the carbon cycle," Alexander Lees, a reader in biodiversity at Manchester Metropolitan University who was not involved in the study, told The Guardian. "Rewilding efforts, including, where appropriate, reintroductions, represent key tools in tackling the intertwined biodiversity and climate crises."

More on climate change: Scientists Say New Material Can Suck Carbon Out of Atmosphere Faster Than Trees