Karen Boggess: A serious miscalculation exaggerated the benefits of bison

For a long time the bison was the largest mammal in Europe. The last wild individuals were exterminated a few hundred years ago, partly because the huge animals were too attractive for trophy hunting.

However, some bison in zoos have survived, at least only about fifty. In recent years, these animals have become the basis of projects aimed at reintroducing them into the wild. Rewilding, as it is called in English. A number of such projects have already begun, including in Poland, Ukraine, Latvia, Lithuania and Romania.

The idea is that bison will influence nature in a positive direction. They will eat grass, semi-grass, bark, and leaves, and will spread the seeds of flowering grasses.

Then the forests They are brighter, more open, and look more like they did in Europe from the Ice Age until a few hundred years ago, when bison themselves became extinct and farmers stopped using forest grazing for cows.

The beneficial impact of bison on biodiversity is fairly indisputable.

But then there's the debate about whether it's good for the climate too. According to the theory, they would bind carbon, among other things, by trampling the soil so that it became more compact. That would be doubly good!

Potential climate impact It is difficult to calculate, and even more difficult to measure in the field. One of the world's leading research groups is located at the prestigious American University of Yale.

It was this research group that the Dutch division of WWF involved WWF Rewilding Europe To write a report. The task was to evaluate the climate benefits of A Visa project in Tarcubergen in Southwest Romania.

Use the research team New model Which they built and worked on – by their own admission – for months before submitting their numbers.

That was exciting!

According to the model, the 170 bison in Tarkobergen will bind as much carbon to the Earth as 1.88 million gasoline cars.

WWF Netherlands She published her report with ambitious journalistic material and beautiful photos. Among the media that took the bait Watchman In Great Britain – a newspaper with a large international readership and ambitious climate monitoring with a dedicated climate editorial office.

One person who also liked the great news was Per Snapprod of Popular Science magazine Research and progress In Sweden. Bear Snapprod did what no one else in the long enough series had done: he reviewed it again with other experts.

Experts appointed by Per Snapprod viewed the WWF report to the core: “far beyond reason,” “too good to be true,” and “the calculations are completely wrong.”

I called per Snaprude then Research group at Yale University He told what his critical experts said. Which prompted researchers at Yale University to go back and check their numbers again. Then they discovered their math error. They had Multiplied One time is too many.

When they used their model correctly it decreased Estimated climate benefits for visitors By 98 percent.

After medication intervention, Bear Sunbrod WWF Netherlands She submitted her report, and The Guardian corrected its article.

Who is this We learn:

Scientific results must be reviewed by other experts in the field (so-called peer review) before they reach the public.

Journalists should be more careful with findings that come from interested organizations and are not published in peer-reviewed scientific journals.

These models can be very wrong if they are not checked against reality.

Exaggerated and incorrect claims about the environment and climate can backfire and cause a lot of damage.

Read more:

Maria Günther: This is how you judge science

Karen Boggess: This is how you distinguish between fake experts and real ones

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