As if proof were needed to tell us that immersing ourselves in the natural world is good for us, the evidence is mounting. All we need to do is look after it better.

For most of my working life making BBC wildlife documentaries, good weather in summer here in the UK, or anywhere in the world on location, were the busiest of times.

Up before dawn and filming until after sunset was normal. Early and late in the day also provides the best light for photography. So, enjoying the best of days here in a deep Devon valley is special, particularly when the heat is rising and only the breath of a breeze stirs the tree tops, sending ripples running across the hay meadows. Overhead a buzzard lazily wheeling catches a thermal of hot air and rises higher without a flicker of wings.

Now the first flush of summer flowers is fading, young grasshoppers are growing fast and their increasing volume of chirping merges with the warmth. More butterflies are taking to the wing, Marbled Whites, Common Blue and Skippers join the Meadow Browns to flit from flower to flower, flying low over the drying grass.

Here, the steep sided hills echo to any sudden sound, the bleat of a sheep or cry of a hunting peregrine. Walking past the old hay barn I can hear the summer hissing of this season’s young barn owls. A soothing, soporific, repetitive snore, that increases as the hard light of day softens into evening haze. The sound urging their parents to go and find them a meal.

For nearly 30 years barn owls have nested here, haunting the fields by night and sometimes early or late in the day.

Being at the top of the food chain, predatory birds are a useful indicator of the abundance of prey. In years when small mammals do well, so too do the creatures that feed on them. In nature everything runs in a cycle. Some short, others much longer, indeed so long they can extend way beyond our own lifetime.

At the other end of the scale many more small lives can be so short they may appear and vanish in a matter of days, even hours. Being at the bottom of a food chain is not a good place to be.

A sudden noise by my feet alerts me to one of the most furious little lives, a shrew. Betraying their existence with a high-pitched twittering, indeed even ultrasonic call, may seem reckless with so many predators about. But this is how one of our smallest mammals announce their presence, to communicate, attract a mate or ward off a threat.

But coming from somewhere in the grass the sound is remarkably hard to pin point as they go about their frantically short lives. Shrews eat and sleep every twenty minutes or so, day in day out for just a single year, if they are lucky. It makes me glad to be human.