Nature Studies by Michael McCarthy: Ireland's corncrakes - no longer in every acre

Are we divided by the same language? There is no doubt that the British Isles – that is, Britain and Ireland combined – constitute a geographical entity. We have the same climate (temperate, moist, and 10 degrees Celsius warmer than it should be, because of the Gulf Stream), the same topography of low mountains, small lakes and relatively short rivers, and the same wildlife. But so ingrained are the social and political differences between the two countries that they are rarely considered together (the Lions rugby team being a rare exception).

One way that the whole archipelago is seen in the round, however, is in the production of bird atlases. There have been two editions of the Atlas of Breeding Birds in Britain and Ireland, one in the early 1970s and another in the early 1990s; now a third will be published next year.

Four years of fieldwork for the new atlas have been completed and the preliminary results paint a fascinating picture of bird gains and losses: during the past two decades, for example, over much of Britain the raven has returned, while the wood warbler and the whinchat have vanished.

These changes we already knew something about, because British breeding bird populations have been annually surveyed, in detail, for nearly half a century. But Ireland's breeding birds have been subject to detailed annual surveys only since 1998, and not all species are covered, so the new atlas will be very important for the Republic: the clearest indication yet of how its avifauna has fared over the past 40 years. And the preliminary results do not all make happy reading.

They show in particular that the birds which might be thought archetypal inhabitants of Ireland's wild west – the waders of the lowland bogs and upland moors such as snipe, lapwing, redshank and curlew – are in serious trouble. Since the last atlas, they have declined, respectively, by 11, 32, 40 and 65 per cent. These figures refer to distribution: the percentage of 10km grid squares on the map where the birds are found. The percentage loss of abundance, of the actual numbers of birds, will be very much greater. Indeed, the curlew in Ireland is in such headlong decline that it may soon go extinct.

The greatest loss of all in the past 20 years, however, is that of the bird which once symbolised agricultural Ireland more than any other: the corncrake. There used to be "a corncrake in every acre", with its rasping call on summer evenings; the new atlas will show that Crex crex has disappeared from 78 per cent of grid squares since 1991, and from 93 per cent since 1972. Modernised farming methods are largely to blame, and the bird is now confined to the coastal strip and offshore islands of the far west, such as Tory Island and the two Inishbofins (one each off Donegal and Galway), with the population reduced to fewer than 150 calling males.

It's not all bad news, though: for instance, two birds which have vastly extended their range in Britain over the past two decades, the buzzard and the little egret, have done the same in Ireland. But the development giving Irish bird-lovers most satisfaction is one which may seem mundane to British birders: the arrival of the woodpeckers.

We all know Ireland has no snakes, thanks to St Patrick; few realised that until recently the country was woodpeckerless, too. That changed when great spotted woodpeckers began breeding in County Wicklow in about 2006; now they're rapidly spreading. "It's a fascinating development," said Brian Caffrey, the Irish Atlas Coordinator. "People are delighted." And having that magnificent flash of black, white and scarlet on their bird feeders, why wouldn't they be?

From an abundance of apple varieties, a rare new winner

Just to wander outside Britain once again: last week in France, I discovered an apple variety that was new to me. I'm not sure if apple anecdotes fit the description of Nature Studies, but I shall mention it because I do feel that orchards, especially old orchards, are a definite part of the natural world.

The apple was called chanteclerc (sometimes spelt without the final c) and it was a dull mustardy yellow, with small brown spots; largish, and flattened at the top and the bottom.

It turns out to be a cross between a famous old French apple, the reinette clochard, and the golden delicious, that monument to insipidity. Nothing insipid about the chanteclerc, though: soon as it touches your tongue, the flesh has an acid bite, which is also perfumed. Fantastic.

I haven't seen it in Britain, so if a supermarket apple buyer is reading this, now's your chance, sunbeam.

m.mccarthy@independent.co.uk; twitter.com/@mjpmccarthy