Apart from the restoration of natural water systems and managing our grazing animals, Knepp is really about letting go - allowing nature to take over. It's about sitting on your hands, with no expectations, and seeing what turns up. And the arrivals are often astonishing. No one could have predicted at the outset of the project, for example, that we would become one of the most important sites in Britain for Turtle Doves and Nightingales. Or that we would have Ravens, Peregrine Falcons, Bechstein's and Barbastelle bats here within just a few years.

It is often tempting to consider Knepp as a site for reintroductions. The kind of habitat emerging here is now so rare in the rest of Britain, and there are so many species under threat or even extinct, that we often receive appeals from ecologists with suggestions of species in need of a helping hand. Knepp could be prime habitat for, say, Corncrakes, Cranes, Osprey, Hedgehogs, Red-backed Shrike, even native plant species.

But the real value of Knepp, we feel, is to wait and see what turns up of its own accord. Nature, we are learning, is often far more resilient than we give it credit for. Hedgehogs disappeared in our last decade of intensive farming but recently seem to be making a comeback on their own. Ospreys have not bred here yet, but are occasional visitors. Rare beetles are on the increase and Water-violets have already begun to spread through our water-courses. We believe it will only be a matter of time before we see our first Greater Horseshoe Bat here, flying in from territory not far away in Midhurst.

Being patient, and giving nature the benefit of the doubt, can reap huge rewards. It can show what can return, given the right conditions, without the need for hugely expensive and time-consuming human interventions.

Issy with rescued beaver kit in Bavaria

Issy with rescued beaver kit in Bavaria

There are, however, some notable exceptions. Beavers, once native to Britain and extinct since the 18th century, are now the subject of a reintroduction trial in Devon. As Chairman of the Beaver Advisory Committee for England, Charlie has, for the past decade or so, been campaigning for greater appreciation of this keystone species and practical guidelines for beaver management. We would love to see beavers back in our Sussex landscape.

Bison were originally on our Letter of Intent to Natural England. Another keystone species, they have been reintroduced with huge success in conservation projects in Europe. Though they pose no threat to humans, they can be aggressive towards dogs (whom they consider to be wolves). So far, though, we have not been able to work out a way of introducing them into Britain that would not conflict with dog-walkers.

a Knepp white stork

The White Stork, which dates back to the Middle Ages in Britain, is another species undergoing successful reintroductions in Europe - notably in Sweden, Poland, France, the Netherlands, Belgium and Switzerland. Young White Storks are usually faithful to their natal site, and depend on an established colony for successful breeding, so these reintroduction programmes use captive birds to seed initial colonies in order to restore these charismatic birds to their former breeding range. DEFRA considers this strategy in Britain to be a 'reinforcement' of the 20 or so birds that currently fly over to the UK from the continent every year. Knepp, in partnership with the Roy Denis Wildlife Foundation, Warsaw Zoo, Cotswold Wildlife Park and a number of private landowners in the southeast, has embarked on an exciting project to re-establish a breeding population of these charismatic birds. Sussex was once a stronghold for these birds and soon we hope to be seeing them building their great nests in big old oaks and and bill-clattering on roof-tops once again.