European bison are becoming unexpected allies of conservationists, simultaneously changing the appearance of forests and stimulating biodiversity on two different fronts – in the ancient forests of Kent in England and in the Carpathians in Romania. More and more data show that these large herbivores act as powerful "ecosystem engineers", which help to restore degraded landscapes.
Wisents in Kent rearrange forest soil
A herd of European bison, released into the Blean forest near Canterbury in Kent, is already having a tangible impact on the local ecosystem just a few years after their arrival, according to data from the "Wilder Blean" project, coordinated by the charities "Kent Wildlife Trust" and "Wildwood Trust". The animals were introduced to the area in 2022 as part of the first initiative in the UK to use bison for natural forest management – an idea inspired by the fact that they are the closest living relatives of the extinct steppe bison, once widespread on the British Isles.
Hannah MacInnes, a wisent keeper and manager of the grazing areas in the reserve, describes the change as visible to the naked eye. In her words, "significantly more light is now reaching the forest floor and we see how species that previously failed to break through the dense shade of trees, ferns and blackberry bushes are starting to develop". The natural behavior of bison – grazing, bark stripping, rolling and felling trees – opens the crowns and creates "patches" of different habitats in which new plants, insects and other small animals find a niche.
In order to expand the range of the herd, new "bridges for wisents" are being built in the area to connect separate sections of the forest and provide the animals with access to a total of about 200 hectares of easy area. Some of these facilities have already been completed, and others are expected to be ready by the end of the year, which will allow the herd to use a much larger territory. The success in Blean is already inspiring new steps: five animals from this herd have been moved to Cumbria to lay the foundations for a second free-living wisent population in the UK.
Romanian herds bring benefits to the climate and biodiversity
In the Romanian Tarcu Mountains, part of the Southern Carpathians, the results of nearly a decade of efforts to reintroduce the European bison are no less impressive. Organizations working on rewilding projects in the area report that in the areas where the herds move freely, the amount of plant biomass and the diversity of species have increased by approximately 30%, forming a complex mosaic of meadows, shrubs and young undergrowth. This changed structure of the habitats creates conditions for more insects, birds and small mammals compared to the monotonous massifs, previously dominated by homogeneous vegetation.
According to "WWF Romania", more than 200 free-ranging wisents now live in the Tarcu Mountains, and on a national scale, the population in the wild exceeds 350 individuals – a significant success against the background of the fact that the species has been extinct from these lands for more than two centuries. The constant increase in the number and range of the herds shows that the conditions in the region can once again support the largest terrestrial mammal on the continent.
Research by the Yale School of Environment links these herds not only to the restoration of biodiversity, but also to measurable climate benefits. The model analysis shows that about 170 bison grazing on approximately 48 square kilometers of grassy habitats help the soils to capture an additional 54,000 tons of carbon annually – approximately ten times more than the same territory would retain without their presence. This value is equated to offsetting the annual emissions of tens of thousands of cars, according to estimates by scientists and environmental organizations.
Plan for the restoration of wildlife
Wildwood Trust executive director Paul Whitfield emphasizes that the project in Kent is designed as the beginning of something bigger. In his words, "the wisents in Blean have always been called upon to be a catalyst for change, showing how these animals, as true "ecosystem engineers", can rearrange the structure of the forest and create conditions for a new rise in biodiversity". Through the announced expansion of the initiative to Cumbria, the idea is to use the accumulated experience to create a network of places where wild herds will naturally support the forests.
With the expansion of populations in the UK and Romania – and with ever clearer evidence of the positive effect on the carbon balance and biological diversity – the return of the European wisent is becoming a living example of how the restoration of key species can help heal degraded landscapes across Europe. For conservationists, these herds are not only a symbol of the rehabilitation of an almost extinct species, but also a practical demonstration of "wild" solutions to the climate and environmental crisis.