Summer birds are on the wane

SEVERAL SPECIES of bird that breed in Ireland are summer migrants that come to us from Africa.

They spend the winter south of the Sahara desert.

Among the best known of these are swallows and martins, cuckoos and corncrakes. And it seems as though the number of these birds arriving here is declining every year.

The corncrake is our only breeding species that’s officially categorised as internationally endangered. But older people who live in the countryside don’t need an official classification to know what’s happening.

They remember the sound of corncrakes calling through the night in early summer and they know that it’s no longer to be heard. And, despite intensive conservation efforts over the past decade or so, corncrakes are still declining in Ireland.

The cuckoo is in a somewhat similar situation, though the decline has not yet reached such a disastrous stage. This year I heard one calling for two or three days around my house. I was delighted because last year, although I heard a couple of cuckoos in other places, not a single one was audible from my garden. And it used to be such a common sound in late spring.

Swallows, sand martins and house martins appear to be in decline as well, although the data for them is not quite as clear. But something else rather interesting has surfaced in recent years. We’ve discovered that some swallows that breed in Britain and Ireland do not return to southern Africa but spend the winter in the south of Spain or in north Africa. It’s not clear whether this has always happened or whether it’s a reaction to recent environmental changes.

All our conservation efforts to try and support these declining species have concentrated on improving conditions for them here.

We have schemes, for example, to encourage changes in the way farmers mow meadows to help nesting corncrakes. But it’s beginning to look as though the main problem may lie elsewhere.

For the past 40 years the Sahara Desert has been getting bigger. There are several reasons for this. One is a decline in rainfall caused by climate change. Another is increased grazing pressure on the desert’s fringes and the effects of a slash-and-burn type of tillage farming to produce millet, which is the staple crop on the southern edge of the desert.

It looks as though the Sahara may now have grown so big that’s it’s difficult for migrating birds to fly across it.

One bird that’s been hit particularly hard is the spotted flycatcher. Forty years ago they were a relatively common breeding species. Less than 20 years ago a pair bred every year in my garden. But they went into a very rapid decline.

IT’S estimated that since the late 1960s, exactly the period when the Sahara started to expand, the numbers of spotted flycatchers breeding in Britain and Ireland has dropped by between 60% and 70%. They’re a very frail little bird and, because they spend the winter right down in the southern tip of Africa, they face an enormous journey twice a year.

But I’m delighted to be able to report a piece of good news. After an absence of around 10 years, a pair of spotted flycatchers returned to my garden. In fact, I found one in my bedroom.

They are among the last of the summer migrants to arrive in this country and they like nesting in holes or crevices in masonry or old trees. By the time they arrive most of the good nest sites have been taken by other species. I had left the bedroom window cracked open and I think the bird had squeezed in to look for a nesting pace.

I released it and wished it the very best of luck.

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