The UK’s first wild bison in millennia have been joined by iron-age pigs, Exmoor ponies and longhorn cattle as the rewilding project moves forward in creating a rich and natural new habitat. The Wilder Blean project in Kent is deploying the animals to replicate the roles played by mega-herbivores when bison, aurochs and wild horses roamed prehistoric England. The animals will be closely monitored as they transform a former commercial pine plantation into a wild wood. The ancient breeds act as ecosystem engineers, with the bison stripping bark from trees and creating the deadwood needed by insects, as well as trampling down corridors of light to spur new plant growth. The ponies complement this by clearing soft vegetation, while the pigs dig around looking for roots and bulbs, spurring new seeds to germinate. The longhorn cattle open up the tree canopy and their actions will be compared with those of the bison. All the changes will encourage bats, birds and other creatures to thrive. “This is where the project really starts to come to fruition,” said Paul Hadaway, of Kent Wildlife Trust (KWT), which runs the project along with the Wildwood Trust. “We’ve had the bison now for eight months settling into this site and doing some amazing stuff. But the intention was always to have as close to a natural grazing assemblage as we could recreate. “If you go back to when these English woodlands first evolved, they would have had mega-herbivores. So this is about returning back to that kind of natural management, to create a much more climate-resilient, adaptable landscape. The pigs are each capable of ploughing about four acres of land a year.” Alison Ruyter, also of KWT, said: “Wilder grazing is about using native wild breeds of livestock to mimic the things that mega-herbivores would have done in the past when wild horses, aurochs and bison roamed around the country.” The five-strong bison herd was completed in December with the arrival of the bull. The surprise birth of a calf was revealed in October. One of the females was already pregnant on arrival in Kent, but bison disguise their pregnancies in order to avoid being targeted by predators. The bison and cattle herds will be accompanied by ponies, with the pigs moving between the two groups. The rewilding success of each group will be compared with an area with no large herbivores and managed by humans. All 9,000 bison living in Europe today are descended from just 12 zoo animals, which rescued the species from extinction in the early 20th century. The Kent bison are currently in a 50-hectare (123-acre) area. But this should expand to 200 hectares in the summer once large tunnels are built to enable the gentle giants to cross public footpaths without encountering people. Rewilding is of increasing interest to conservationists in the UK, where populations of the UK’s most important wildlife have plummeted by an average of 60% since 1970. Intensive farming has left Britain as one of the most nature-depleted countries in the world.