How can our flora and fauna best be nurtured and protected? This question has vexed ecologists, wildlife trusts, and animal and plant charities for many years now, and there is no single answer. In some cases animals and plants have to be conserved on a single-species basis, as for example with the reintroduction of the red kite or the white-tailed sea eagle, whereas others, such as the large blue butterfly, require the conservation of an entire habitat together with detailed knowledge of how the target species utilises it. There are also concerns about inbreeding if the population size of a species is small, or about genetic introgression from another species, as happens when Scottish wild cats interbreed with feral domestic cats.

But if we stand back and take a look at the whole conservation scenario in Britain and Ireland, one can detect a shift of emphasis over the last 50 years or so. Originally there was a policy of identifying threatened wildlife communities which contained particularly vulnerable species, and constructing fences around the community to limit disturbance. In extremis the area might be closed to the public. More recently the emphasis has swung towards active management, recognising that even if a community is fenced off and isolated, it is still affected by neighbouring human activity as evidenced by air pollution, or climate change, or reduction in the numbers of migrant species visiting the area. Active management may sometimes also involve reintroduction or translocation of individuals, or culling of troublesome predator species.