A decade of birds
THE IDEAL TIME TO REFLECT Here, we look at how UK bird populations and distributions have changed over the past decade...
Facts and figures on how bird populations have changed over the past decade
At the start of March, it will be 35 years since Bird Watching first appeared on the news-stands. Not for the first time, it set me thinking about what has changed, in terms of UK bird populations and distributions, since then.
But then my thoughts turned to what’s happened far more recently – in the last 10 years. Things are constantly changing. But are they changing as much, as fast, or in exactly the way that we sometimes think?
Let me give you an example. I talked to a fellow birder recently, as we looked out across a wide expanse of wintry wetland. We each started checking off all the expected duck species – Mallard,
Gadwall, Wigeon, Teal, Tufted Duck, Shoveler, and a few Goldeneye – and at the same time both started to bemoan the absence of Pochards.
Even 10 years ago, I could be confident of seeing a good scattering of them on my inland patch in winter. Now, seeing even one is a red-letter day. So what’s happened? And should we be worried?
The first thing to point out is that Pochards are rare breeding birds in the UK, with maybe around 650 pairs, mainly in eastern England and Scotland, and in Northern Ireland. This number has actually increased slightly in recent years.
But most of the Pochards we see in winter are migrants arriving from eastern Europe and Russia, and numbers are down by 60 per cent since the 1980s.
There are no firm figures to suggest that decline has sped up in the last decade; but the general trend backs up what lots of birders have observed.
The reasons for the decline are several – food shortages caused by algae and plants on water bodies, because of nutrients washing off farmland; a decline in Black-headed Gull numbers (Pochards like to build their nests among them); and predation, largely by American Mink.
In addition, it’s possible that global warming means that the birds aren’t having to travel so far west in winter – that’s certainly the case with some of our other winter wildfowl, such as Bewick’s Swans. So, yes, in this case we should be worried – one way or another Pochards are having a hard time of it.
Success story
Egrets and herons, on the other hand, are the undoubted avian success story of the last decade, and the one before that, and the one before that...
Not much longer than 10 years ago,
I can remember seeing a Great White Egret at Cossington Meadows, one of the Leicestershire sites that I regularly watched at the time. It was a big deal. A really big deal. Lots of stars next to the sighting in my notebook, and a totally unexpected county year tick.
Revisiting the same site recently, and the nearby reservoirs of Charnwood Forest, and there were Great Whites everywhere, in ones and twos. And a couple of years ago, in a hide at Rutland Water (maybe 20 miles away), I sat with half a dozen birders watching a Glossy
Ibis, intently. All of us, I’m ashamed to say, were positively blasé about the eight Great White Egrets on the same lagoon, and barely gave them a second glance.
Little Egrets have continued to increase in number and spread in range, Cattle Egrets are starting to add the UK to their bid for world domination; and the likes of Purple Heron, Night Heron and Little Bittern have all bred here.
We can give ourselves a small pat on the back – conservation of good wetland habitat, and creation of new swathes of such habitat, have undoubtedly helped these species to find homes here. Glossy Ibis, incidentally, is another bird now being seen in the UK much more regularly. In part it, too, has benefited from all that wetland habitat, and a warming climate; and the success of populations elsewhere in France, Spain and Portugal is probably creating an overflow effect.
But, as always, it can take a while for published stats to catch up with reality. The RSPB’s website for example, says there are about 35 Great White Egrets in the UK each winter, but the real number must be well in excess of that. So bear that in mind with all birds – don’t discount a possible sighting purely because a field guide or website suggests it’s very unlikely.
Prey confusion
There are examples, too, of where the situation is a great deal more confused. Take birds of prey. It’s certainly true that raptor persecution is a major problem, especially on grouse-shooting estates. One species in particular – the Hen Harrier – is the victim of most of that persecution, although the likes of Buzzard and Golden Eagle (and pretty much any raptor on occasion) also suffer.
But the populations of most British birds of prey are at levels that probably haven’t been seen since the late medieval period. Not that that’s a bad thing at all, of course – left to themselves, populations will find a natural level, depending on availability of food and nest sites.
So, Red Kites have continued their inexorable spread over the last decade, with the populations from the various reintroduction schemes starting to join up.
White-tailed Eagles are thriving in Scotland, and even before the Isle of Wight
IT’S CERTAINLY TRUE THAT RAPTOR PERSECUTION IS A MAJOR PROBLEM, ESPECIALLY ON GROUSE-SHOOTING ESTATES...