Bison are considered to be “ecosystem engineers” because their natural behaviour, such as browsing, grazing, felling trees and trampling vegetation, helps to create habitats for other plants and animals.
Heidi Aguirregoicoa, bison and conservation ranger at Kent Wildlife Trust, said: “It’s been fascinating to watch the bison gain confidence with the bridges.
“At first, they were cautious and their first crossing happened under cover of darkness, but they quickly started using them more regularly.”
Rangers were already seeing their impact on the woodland, she added.
“Fresh paths are appearing through dense vegetation, bark is being stripped from trees and their dung is enriching the soil and supporting insect life,” she said.