There is a wheatear on the beach this morning. A male; the soot black of his bill and mask is picked up in his wing. From here it stripes along his flight feathers to his tail and legs, making an inky zigzag. His back is silver; his throat is apricot, a colour faintly picked up in his vent. Black, apricot and silver are also in the Norfolk shingle of Salthouse beach, echoing this wheatear all the way from Weybourne to the tip of Blakeney Point.

He is a wheatear, yes; also a promise of longer days, and warmer, as are the Sandwich terns rasping north of me, over the sea. More though, this wheatear hopping through the tattered waste of last year's poppies, is my passport to the northern moors and tundra. He is my portal to a songpost there, among the heather, sedge and stunted birches of his habitat, and to a burst of song, half scratchy, half melodious.

This wheatear, freshly here from Africa, takes me with him to the moors where he will meet a toffee-coloured female, dun-backed, her white rump flashing as she scuds along a stony path. His song will woo her to his territory, where they will mate and - in a rabbit burrow or a hollow deep under rocks - she will lay a clutch of little eggs, the pale blue of a summer sunrise. These she will incubate for 14 days and, together, they will feed the nest-bound chicks for two weeks more, stuffing them with insects until they tumble, barely ready, into the world.

In autumn, perhaps, I'll see one of these moor-raised chicks in Norfolk, making its first migration, in search of winter warmth and food. Heeding its genes and instincts, it will not know it is a part of nature's greatest tide of life, bearing nitrogen and carbon from northern uplands south to Africa. There, some brother or sister human, whom I will never meet, will see the well-known bird, and smile, and wonder where it's been, dreaming of far-off landscapes, as I do too.

He is a wheatear, yes, this beautiful bird among the myriad flints on Salthouse beach, but he is more. He is my pathway hundreds of miles to the north and thousands south. He is a symbol of a wide world shared between biodiversity and humanity.

Male wheatear by Darren Williams

You know what happens now. I tell you just how badly we've messed things up. How we have breached the contract between humans, wild landscape and other forms of life, pushing both biodiversity and the environment into crisis. It's true, we have, but this is not the end. Just as the wheatear at my feet is heading north to breed, so too a journey stretches out ahead of us. And we can choose the path.

If we have learned one thing from these last two gruelling years, surely it is that we can change, adapt, do different. Just as our prodigious intellect has allowed us to develop technology and cleave ourselves from our essential place in nature - to the desperate detriment of landscape, wildlife and ourselves - so too our intellect can guide us back to living sustainably with the natural world. It will take humility, ingenuity and willingness to change. But environmental scientists speak with one united voice: if we do not change - and fast - we threaten the very future of life on Earth.

So, we must change. Indeed, we are already changing. A dear friend - a visionary naturalist and conservationist - has a riotous North Norfolk garden. In the middle is a meadow, where pyramidal, bee and common spotted orchids bloom, and skippers flit between nectar-laden flowers. Around the edge a giant border of perennials heaves with peacocks, painted ladies, red admirals and commas, with bees and hoverflies. On sunny days his tousled grass is deafening, as Roesel's bush-crickets, meadow and field grasshoppers stridulate. In spring his three ponds roar with amorous frogs and toads, while in the shadows, smooth and great crested newts flash their outlandish tails. Nearby, his organic plot yields an abundance of fruit and vegetables for the family.

My friend grew up on a farm. His stepfather, who lives nearby, was the kind of farmer who embraced the 20th century modernisation of the countryside, tearing out hedges, filling ponds, and lacing the land with pesticides and fertilisers. This was the way - efficient, rational and profitable - and nobody's intention was to harm wildlife or the environment. My friend, though, loving nature as he loves his life, was tortured by the loss of birds and insects, voles and flowers, from the fields in which he grew.

Wheatear by Terry Postle

Last summer, his stepfather brought a group of friends - all farmers in their 80s - to visit his wondrous garden. 'You see this,' he said to them, 'this is the future.' Likewise, earlier this year, my sister-in-law told me that two days each week her family were eating vegetarian, to limit their environmental impacts. I've been vegetarian for 30 years, vegan for many of them. I've never encouraged friends or family to follow suit - I've never lobbied, because it's not my place - but not long ago, my eldest niece told me that many changes in our family came about because of me.

My point is not to signal virtue - not one bit - but that, just by being our authentic selves in relation to the environment or any other cause, we influence those around us positively. My friend's organic, peat-free garden has shown farmers in their 80s that a different path is possible and essential.

So, as this dapper wheatear migrates north to breed - to pass his genes another generation forward - let us all live as sustainably as we can. Doing so, we spread the word; we share with others the joy of living within nature's means. Of making momentary friends with wheatears on a pebbly beach and promising them a future on this Earth.

Header image: Wheatear by Elizabeth Dack

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