Picture this: 15,000 years ago, mammoths, woolly rhinoceroses, giant deer, prehistoric horses and European bison roamed the vast forests of the continent. Today, all of them have vanished, except one: the European bison. But it was a close call.

The European bison should not be confused with its cousin, the American bison. The two have lived on different continents for more than 10,000 years. They do share a common ancestor, which gives them a similar appearance. But the European bison has its own distinctive features: it is slightly taller and more slender, its hump is somewhat less pronounced, its back straighter, and its horns closer together. It weighs between 600 and 900 kg and stands at around 1.80 m tall.

A last‑minute rescue

As recently as a thousand years ago, herds of European bison populated the continent, from Spain to the Caucasus. But hunting, deforestation and human activity gradually drove them back. They disappeared first from France, between the 8th and 10th centuries, then from Germany in the 17th century, and from Romania in the 19th century.

By the end of the 19th century, only two wild populations remained: one in the Białowieża Forest, straddling Poland and Belarus, and known as one of the last primal forests in Europe, and the other in the Western Caucasus.

Even these last two populations, however, only survived only a few more years. The Białowieża Forest population was declared extinct in 1919, shortly after World War I. During the war, German soldiers occupied the forest and hunted the bison for meat. As for the Caucasus population, its last member was shot by a poacher in 1927.

From that point on, the survival of the species depended solely on around fifty European bison held in captivity in zoos or private nature parks. Faced with this bleak situation, a few enthusiasts decided to fight for their conservation through breeding programmes.

Year after year, their numbers slowly increased. By the 1950s, the first bison were released back into the wild in the Białowieża Forest. Further reintroductions followed in Eastern Europe. Since 2014, bison have been reintroduced to Romania’s Țarcu Mountains (part of the Carpathians), in the heart of a Natura 2000 site, thanks to the EU’s LIFE programme.

This approach follows the principle of “rewilding”, which the French National Museum of Natural History in Paris defines as “promoting the return of wild flora and fauna that once inhabited an area”.

Data from the European Bison Pedigree Book shows that the estimated number of free-living European bison has risen from 3,310 in 2013 to 8,225 in 2023, with the largest herds found in Belarus and Poland. Around 200 bison now live in the wild in the Romanian Carpathians.

A boon for Europe

According to scientific studies, the reintroduction of European bison has had highly positive effects on biodiversity. By altering the structure of the landscape it inhabits, the animal plays a key ecological role.

Across its range, it spreads nutrients through its dung and carries seeds that get caught in its coat. In this way, it helps disperse dozens of plant species, boosting floral diversity and supporting pollinators. As it moves, it breaks low branches and shrubs, opens up thickets, strips bark from trees – sometimes killing them – and creates patches of bare soil by rolling on the ground. The result is gaps and even clearings in the forest, which allow light to reach the forest floor again, enabling pioneer plants to take hold.

In spring, during breeding season, birds make use of the winter coat that bison begin to shed to build their nests. Bison hair is woolly and soft, providing good insulation and an ideal temperature for eggs.

Thus, everywhere bison are reintroduced, as vegetation becomes more diverse, new habitats form that are suitable for other species. Conserving the bison therefore generates broad ecological benefits for the whole region.

Restoring this species could also help slow global warming, according to a recent study currently under peer review by a scientific journal. Thanks to their massive body size, European bison compact the soil, which helps keep carbon locked in the ground.

The researchers, which included Oswald J. Schmitz of the Yale School of the Environment, studied the herd reintroduced in the Țarcu Mountains, using its current grazing area of 172 km². According to their calculations, this environment is estimated to now capture 3,091 tonnes of CO₂ per year, an increase of 18% compared to the period before reintroduction.

This CO₂ capture could even rise to 35,450 tonnes per year as European bison grow in number and spread to occupy the full 592 km² of grasslands and forest openings available to them in the Romanian Carpathians.

European bison have also helped reinvigorate the areas where they have been reintroduced. In Armeniș, a small village in the Romanian Carpathians nestled between forest and pasture, their return has breathed new life into the local economy and tourism. “An entire region is coming back to life. It is a rare success story, and above all a profoundly collective one,” explains WWF, the NGO that has supported this reintroduction.

Together with local stakeholders, WWF has helped the Armeniș community develop ecotourism and entrepreneurship, and promote its traditional skills. Among the activities that have flourished are guided walks to observe bison, accommodation built with local materials, as well as traditional cuisine and crafts.

A species that remains fragile

Thanks to sustained conservation efforts, in July 2020 the European bison was moved from the “vulnerable” category to “near threatened” on the updated IUCN (International Union for Conservation of Nature) Red List of Threatened Species. Although this change of status is encouraging, it should not be misunderstood: the bison only narrowly escaped extinction and remains a highly fragile species.

Reintroduced populations are often small, isolated and geographically distant from one another, which limits genetic exchange and increases the risk of inbreeding. In the long term, this fragility could undermine the species’ viability. Poaching and restricted living space also weigh heavily on the bison. In 2019, only eight free‑ranging sub‑populations had a viable size (150 animals), according to the IUCN.

Moreover, as during World War I, bison are vulnerable to conflicts tearing through the European continent. A case in point is the Białowieża Forest, which has fallen victim to what the Polish authorities call a “hybrid war” launched by Belarus in the summer of 2021. Tens of thousands of migrants attempted to cross the Polish border from Belarus to enter the EU, triggering a major migration crisis. The EU accuses the Belarusian regime of orchestrating this influx together with Russia.

In 2022, Poland built a wall along the border with Belarus to block the arrival of migrants. The result is a barrier that cuts the Białowieża Forest in two and severely hampers the movement of bison. Several animals have become trapped in corridors between the fences, suffering injuries as a consequence. The European bison, therefore, is still a long way from reclaiming its rightful place in the European landscape.
 

Justine Hagard