Bison and horses are re-establishing a natural balance in the area by eating dangerous and invasive plants.
A former Soviet military base is slowly turning into a biodiversity haven thanks to the introduction of wild horses, bison and other big-hooded animals that centuries ago used to roam freely across Europe.
The former Milovice base, located 35 kilometres northeast of Prague, was occupied by the Soviets in 1968, during the invasion of Czechoslovakia, but was abandoned in 1991 following the dissolution of the USSR.
It was then taken over by invasive plants - which are species non-native to a specific place that spread to a degree that can be harmful to the native ones.
Things began to change five years ago, when the area started to be populated by animals that love eating invasive plants, thus reshaping the ecosystem by "saving" the endangered ones.
The animals were selected by the conservationists on a scientific basis.
Domestic animals such as sheep, for example, were ruled out because they would feed on endangered plants.
On the contrary, wild horses love to eat invasive grasses, while bison and tauros prefer bushes, creating a good environmental balance.
Their "environmental-maintenance" is also cheaper than a mechanical one.
Conservationists hope the sanctuary will grow by a third this year, reaching 360 hectares.
Dalibor Dostal, director of European Wildlife, an organisation involved in the project, stated that the area saw "a miraculous change".
“Nobody expected that the whole process would go ahead so fast and the area would change so much in just a few years.”
He said the large animals are as key in preserving the ecosystem "as trees are for forests.”
The project now counts herds of 27 European bisons and some 70 wild horses.
The wild horses were brought from Exmoor National Park in south-western England, while European bison came from Polish reserves.
The work the animals are doing has also helped precious flowers to bloom, like the star gentian, also known as cross gentian. At the same time, insects are also coming back, like the Adonis blue butterfly, which hadn't been spotted in the area since 1967.
“If we give nature a chance, if we give it time and space, it can take care of many things,” said Miloslav Jirku, a biologist with the Czech Academy of Sciences who is involved in the project.
“At the very beginning, I thought that lots of species that used to be here in the 1990s would have to be returned artificially. Today, a number of them are already here without us doing anything about it.”