Teals make an early arrival

I HAVE a friend who’s keen on duck shooting.

The duck shooting season started on September 1 and, as an annual ritual, on this day my friend is in place by dawn, hiding out in one of his favourite spots. When I met him the other day he was quite excited because he’d shot a good bag of teal.

Now this is interesting because these little ducks are rare and declining as an Irish breeding bird. At the last count in 2002 there were only between 350 and 550 breeding pairs in the country.

What’s more almost all were in the northwest and my friend had been shooting in Co Wexford.

About 50,000 extra teal migrate to Ireland in the autumn from northern Europe and these provide a legitimate quarry for wildfowlers. They often arrive at the end of September, several weeks before most of our wintering ducks and geese, but my friend had never before seen them as early as the first of the month.

There’s no doubt that what he’d seen were winter migrant teal. There were several sizeable flocks amounting to hundreds of birds. So why had they arrived early this year? I didn’t have an answer to the question.

Teal feed by upending in the water and by dabbling in the surface. They eat water plants and some invertebrates. The reason they come to Ireland in the winter is because the open water in their breeding grounds freezes over and they can no longer feed.

But because of global warming the autumn freeze-up is happening later every year in the sub-arctic. The logic of this is that if teal are going to change their habits they should be arriving later here, not earlier. It’s just one of several puzzling paradoxes to do with wildlife and climate change.

Whooper swans are another example of a species that seems to be going against the trend. They also breed across the European sub-arctic, although the Irish wintering population seems to be exclusively from Iceland.

But just over 20 years ago they established a small breeding population in Co Donegal and since then more of them seem to have given up migration and are spending the whole year here. Nowadays whooper swans are not uncommon on the Shannon in summer. About the same time, the same changing pattern was recorded in Britain and in southern and central Sweden. This is the opposite to what you would expect as a result of global warming.

There has also been an increase in the sightings of snowy owls in this country. This large bird of prey is a real tundra specialist that feeds on lemmings and similar rodents. Its plumage is white, with a few dark flecks to give it camouflage in the snow. This must be a distinct disadvantage if it’s trying to get a meal in Ireland, so why does it come here? Not all birds are as contrary as this. The arrival of the little egret in southern Ireland from southern France is exactly the type of northward expansion you would expect. And there are some indications the cattle egret may be doing the same thing.

Sea fish are also doing what they’re supposed to, with more and more tropical species such as trigger fish and sunfish turning up in Irish waters. And the bass, which likes warm water, was once largely confined to our southern coasts but is now found everywhere. Some species of dragonfly have also colonised the country from warmer places to the south. But those early teals are a bit of a mystery.

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