A career in conservation derives from an appreciation, wonder and, hopefully, some understanding of nature. This started with a sense of place and adventure - one of my earliest memories, as a four-year-old, crawling under arches of bracken on the local peatbog near my home in south Yorkshire. It was soon extended with wonder when my father, who worked for the peat digging company Finsons, brought home natural objects - the tail of a lizard, dropped to distract a ‘predator’ - still wriggling several hours later; an emerging dragonfly; beetle remains from within the peat (origins of a life-long interest in beetles).

As a teenage bird-watcher, on lowland bogs whose birds were exciting (wintering rough-legged buzzards, breeding nightjars and nightingales) but could be few and far between, I developed a sense of exploration and discovery, when I re-found species supposedly extinct locally (large heath butterfly and bog bush-crickets), and not long after, insects and plants new to the county and to Britain. So now I can be as thrilled by a beetle or a lichen as I was as a teenage birder finding a wall-creeper or a killdeer plover.

The historical perspective also absorbed me from the start – reading minute-books of local societies in the 1870s, knowing that people like me were making the same discoveries. Being the first person to look at the lichens on the moors a century later provided a frisson which I can still remember.

For me, the answer is three-fold, each equally valid:

• emotionally and spiritually, because the stuff of nature makes life worth living – it’s where I spend my lunchtimes, weekends and holidays; as enriching as anything which literature, music or art can provide.
• rationally, because we are dependent on natural systems for food, clean water and air, and we’ve so little idea of the value and applications of biodiversity for sustaining human life. And there’s abundant evidence that living closer to nature keeps us physically and mentally healthier for longer.
• economically, because living and working with the grain of nature is sustainable and less costly (in many ways) than the alternatives. The most basic greenspace in our living and working environment makes us healthier and more productive.

The answers arise from the why of conservation: if we care about the breadth and the detail of wildlife and landscape, we want all of it, everywhere that it ‘naturally’ occurs. Losing one ant or moss species from a place where it’s been known in the past feels like a failure of conservation.

I’ve been brought up with the thinking of British conservationists of the generation of the great Derek Ratcliffe and Norman Moore, who produced the first detailed criteria for evaluating the natural and semi-natural habitats which have survived in the hugely human-modified landscape of Britain. This developed the rationale that, as a minimum, all species and habitats should be enabled to survive and thrive throughout their natural range. A Cambridgeshire peat-bog is different from a Yorkshire or Scottish one by virtue of its ‘Cambridgeness’. So, we should fight to prevent reductions in species range, to retain outlying populations of common species, as well as conserving rare species and habitats. So far, our track record is not a glowing success: it’s sobering to reflect that most of England’s forest clearance was complete by the time the Romans arrived in Britain, that the first regional extinctions caused by human activity could date from even earlier, and the first losses due to industrial pollution date from the Norman conquest. Yet we still enjoy a country rich in wildlife, and for the past 60 years of this Wildlife Trust conservation locally has grown stronger.

Taking the economic justification for conservation, if we want effective floodplains which keep homes and factories out of the water, we may not care whether they are species-rich grasslands with breeding godwits, or a monoculture.

The what also depends on some level of knowledge: many campaigners for the English landscape want a green and ‘rural’ landscape, preferably with some cows or sheep in it, but may not be bothered if it’s the green of orange foxtail or of Italian rye-grass. As a wildlife conservationist, I care about the detail, and I want wet grasslands to support breeding black-tailed godwits and wintering golden plovers and wigeon in huge flocks, as well as a green and pleasant view.

How follows on from why and what? I used to see the role of conservation as protecting what has, by chance, survived to the present time. As a grew up and trained as an ecologist, I became aware of the gradual but inevitable erosion of biodiversity within isolated protected sites, first from ‘island biogeography’ theory in the 1960s - which showed that species would become extinct on an individual nature reserve by chance, and would survive in an area only if they were able to recolonise from nearby ‘islands’ of habitats. By the 1990s, concepts had been refined in the theory of ‘metapopulation dynamics’ which brought the realisation that the landscape is a patchwork of good and bad habitat islands with a surrounding inhospitable mosaic, through which species could move with greater or less ease. This framework arose at the same time that rapid changes in species distribution began to be recorded as a result of climate change, with the conclusion that conservation needed larger areas, and better connectivity and permeability.

So landscape-scale - Living Landscapes in the Wildlife Trusts - is the right approach. I’m proud that the idea started with our own Great Fen, and spread so rapidly across the Wildlife Trusts movement. Landscape scale is the only way of enabling wildlife to adapt to climate change, and it happens also to help magnify and join up the potential of ecosystem services. And as our local population grows, it will provide the larger areas for recreation and enjoyment which people need.