I've just finished reading Michael McCarthy's fascinating, beautifully written, and profoundly depressing book, Say Goodbye the the Cuckoo. His main message seems to be: ' Over the centuries the annual return of spring migrants like nightingales, swallows, warblers and cuckoos has brought joy to millions of people. They were so ubiquitous that in the past these birds became an integral part of our lives. But over the last 50 years or so the numbers of birds heralding the arrival of spring has plummeted. The reasons for their decline are as complex as they seem to be insoluble, and are mostly to do with climate change, intensive farming and urbanisation. Worst of all, the chances are that there will come a time in the not too distant future when they may not come at all.'
Imagine that. A spring when you wait in vain for the screaming swifts zooming between the houses like fighter patrols; no house martins zipping to and from their under-eaves nests with beakfuls of insects for their chicks; no cuckoos' calls to tell you summer is definitely here - whatever the weather says.
You could argue that so many people now live in cities that the loss of these iconic summer birds would scarcely be noticed - but I suspect that's not true. I think that even if we don't consciously notice them, many of us are aware of their presence at some subliminal level, and that if they did disappear people would feel their absence keenly.
But it's the Joni Mitchell conundrum: 'You don't know what you've got till it's gone'. How do you get people to want to take action to save something that they don't realise they value?