If you take even a passing interest in all matters natural, you'll likely have come across the term 'rewilding' recently, a concept that has been steadily gaining traction and ardent supporters. So what does it mean exactly?
Rewilding is an attempt to create the conditions in which natural ecosystems can do what they do without the negative impact of civilization. Rather than trying to turn back time or preserve what once was, this approach recognises that nature is itself in a constant state of flux, each species being intimately connected with a myriad of others, often in ways we struggle to see for ourselves.
Ecologists now use the term 'trophic cascade' to describe natural processes that link animals at the very top of the food chain to those at the bottom. For example a high level predator can, over time, transform the landscape around them as brought to life in the two videos below looking at the impact of wolves and whales on their respective ecosystems.
There are also certain missing animals in an ecosystem that have become known as keystone species, such as the beaver, with an impact on its environment that cascades through to influence a large number of other species. Beavers build dams out of branches and trees which not only slow down the flow of rivers but in turn create habitats for voles, otters, ducks and frogs.
Reintroducing beavers is therefore a way to increase trophic diversity, or as George Monbiot puts it in his book Feral, "enhancing the number of opportunities for animals, plants and other creatures to feed on each other, to rebuild the broken strands in the web of life".
One of the key dangers in assessing this kind of ecological impact is something known as 'shifting baseline syndrome' whereby each generation has a tendency to look back only as far as its own childhood, or perhaps a generation back, when assessing how much the situation has changed whereas the true timescales involved are far far greater.
Anyone living in the UK today may very well look at the many rolling green hills and assume that they are untouched corners of countryside whereas in fact those same fields used to be dense closed canopy forest. For the past 6000 years, grazing sheep have transformed much of the country from dense forest to open forest, to scrub and finally heath. The countryside may look leafy therefore but it is not how it used to be. Grazing sheep prevent woodland from regenerating yet sheep farming has been heavily subsidized here since the Second World War. Perspective is everything.