Monitoring Reintroduced European Bison

Using GPS collars and camera traps

Like many European countries, Spain is undergoing a process of widespread land abandonment. For decades, the landscape in Andalucía has been shaped by grazing by both wild and domestic herbivores. The current trend of abandoning livestock grazing activities and removing livestock from the landscape is having serious consequences for the open and semi-open habitats that many species there thrive on, such as wild rabbits (Oryctolagus cuniculus) and red-legged partridges (Alectoris rufa), important prey species for the endangered Iberian lynx (Lynx pardinus). As open areas become dense with vegetation, they also become more at risk of forest fires. The European bison (Bison bonasus), or wisent, is the largest herbivore in Europe and is considered a keystone species, having a profound impact on the landscape through its grazing and trampling behaviour. Listed as Near Threatened on the IUCN red list, their reintroduction to the Spanish landscape could have profound benefits for restoring these vital habitats and supporting the range expansion of the rare European bison. 

The Intervention

In October and November 2020, 18 bison were reintroduced to the El Encinarejo property by the dedicated owners and bison experts at the European Bison Conservation Centre of Spain. This project is intended to act as example to others in Spain of a more sustainable approach to land management and nature and species conservation. Detailed monitoring of the impacts of the bison on the landscape, habitat use, foraging behaviour and species interactions will be carried out to gather this vital information. By demonstrating how European bison behave in a Spanish ecosystem, with minimal human interference, the project hopes to ultimately inspire and inform further reintroductions on large properties in the Andalucian region and beyond. 

To support the project at El Encinarejo to gather the data they need, Mossy Earth is sponsoring the purchase of a GPS collar and three camera traps. The GPS collar will gather detailed data on their movements across the landscape. The camera traps, placed strategically at important sites, such as wallowing sites, where bison repeatedly roll around for grooming purposes, will provide important behavioural data. 

A scientist sets up a camera trap on a tree trunk in the middle of the image, with dense trees and shrubs, and moss covered rocks in the background.
Camera traps will be installed at key locations across the landscape to collect behavioural data.

Learn More About the Context Behind this Project

A Vulnerable Species

Similar to the North American bison (or American buffalo), the¬†European bison has suffered a dark history at the hands of humans.¬†After decades of over-hunting and habitat loss, only two populations survived in Europe¬†by the¬†20th¬†century.¬†One was in the remote Northern Caucasus Mountains of Russia and another was in Poland‚Äôs BiaŇāowieŇľa Forest, where a herd of around 600 bison remained. The last wild bison were killed during World War I and the Russian revolution, but thankfully a few individuals survived in captivity. Efforts to reintroduce bison back to the wild began in the 1950s in Poland and thanks¬†to further captive breeding and reintroduction efforts, like the one underway at El Encinarejo, there are now around 6,000 wild and semi-wild bison in Europe¬†living in Poland, Romania, Czech Republic, The Netherlands and elsewhere.

A scientist stands in the right of the image observing bison in the distance among scattered trees.
Ambitious efforts by conservation groups and scientists have brought bison back from the brink of extinction.

A Keystone Species

Reintroductions are an important mechanism for expanding the range of European bison and safeguarding the long-term survival of the species, but they also have the potential to contribute to the restoration and sustainable management of grassland and semi-open habitats in Europe. Just like the American bison, European bison can help create and maintain grasslands and semi-open forests, supporting a wealth of insects and birds, through their foraging. Other ungulates benefit too, due to the landscape engineering work of the bison. They also disturb and aerate the soil through their wallowing and trampling behaviour and fertilize the land through their dung.

A bison stands with its heard lowered grazing on the left hand size of the image next to a dead tree. Dense green vegetation covers the background.
Bison play an important role as keystone species in open and semi-open habitats.

Contributing to the Area’s Ambitious Rewilding Goals

The intervention area encompasses what’s known as a dehesa landscape, a multifunctional agroforestry landscape comprising a mosaic of open grasslands with scattered evergreen trees, including oaks, and areas of more closed canopy. It is home to a number of conservation priority species such as the endangered Iberian Lynx, the vulnerable Spanish Imperial Eagle (Aquila adalberti) and near threatened Cinereous Vulture (Aegypius monachus). The bison monitoring efforts are part of an ambitious landscape-level approach that aims to restore this unique habitat and conserve the rare species that call El Encinarejo home. 

In the foreground are brown rocks and bare soil, with scattered shrubs and trees in the background climbing up a tall mountain ridge.
The bison reintroduction and monitoring project is part of an ambitious landscape-level approach to rewild the landscape.

Sources & further reading

Peer Reviewed Research Section
  1. ‚ÄúConservation implications of the refugee species concept and the European bison: king of the forest or refugee in a marginal habitat?‚ÄĚ - EcographyExternal linkIcon Peer Review
  2. ‚ÄúGenetic status of the European bison Bison bonasus after extinction in the wild and subsequent recovery‚ÄĚ - Mammal ReviewExternal linkIcon Peer Review
Heart Image

the team behind the project

Team Member

Yvonne Kemp, Lead Ecologist, European Bison Conservation Center of Spain

Team Member

Fernando Moran, Director, ‚ÄéEuropean Bison Conservation Center of Spain

Team Member

Alexander Hohne, Landowner, El Encinarejo

Team Member

Guy Murdoch, Landowner, El Encinarejo

Team Member

Justo Martín Martín, Biologist, ‎European Bison Conservation Center of Spain

Team Member

Hannah Kirkland, Conservation Biologist, Mossy Earth