FORTY years after the osprey returned to colonise Scotland, the fish-eating bird of prey has bred so successfully that it is set to extend its range over the border to England, where it has been extinct for more than a century.
From the single pair that nested atop a Highland pine at Loch Garten near Aviemore in 1954, the Scottish population of this spectacular hawk this summer reached 95 pairs, which produced 146 young. Breeding ospreys have now spread their range in all directions and very soon, says Chris Harbard of the Royal Society for the Protection of Birds, which has carefully supervised the increase, the only direction for them to go will be south, to England.
'We would certainly expect them to breed in northern England by the end of the decade,' said Mr Harbard, 'but really it could be any year that a couple of birds find a nice English reservoir and say, we'll stay here. The rate of increase is now very steep.'
Richard Thaxton, who has run the RSPB's osprey centre at Loch Garten for the past 10 years, said: 'In recent years English conservationists have had no success in attracting migrating ospreys.
'But given the way the numbers are going in Scotland, the birds will go over the wall sooner rather than later. There are plenty of good nesting sites in the Kielder Forest in Northumberland and in Cumbria, which lie alongside suitable fishing habitats. It is now simply a matter of waiting.'
At present the birds, which take large trout from the surface of lochs or rivers in a swoop unforgettable to anyone lucky enough to witness it, migrate south to Africa.
If any do make more than a passing stop in England on their return next spring from the Gambia and Senegal, it will reverse more than 100 years of steady decline. In the early 19th century, ospreys were common in Britain, with around 1,000 pairs north and south of the border. But by the turn of the century, the birds had been hunted out of existence in England and the last Scottish pair bred during the First World War.
It was 40 years before the next two young were spotted at Loch Garten. Ornithologists watched nervously between 1954 and 1959 as one bird was shot and a dozen eggs were stolen from nests. But, under RSPB protection, another pair reared three young at the newly established reserve there in 1959, and in that year the conservation body took the bold step of opening the site to the public.
Officials were astonished by the response. Some 14,000 people came in the first year. As more ospreys settled, the number of human visitors increased.
Despite several setbacks - in the 1980s 10 nests were attacked and vandals attempted to fell a nesting tree - the number of pairs continued to rise to 50 in 1987.
This year so far 44,000 people have journeyed to Boat of Garten, which has become known as 'osprey village', to view the birds, and in all more than 1 million people have observed them in the wild or via a video link with an eyrie.
Officials at Loch Garten say that with 'core' Highland nesting sites now protected by 24- hour surveillance, the threat to the osprey is over. Mr Thaxton at the RSPB said: 'The place is buzzing this year with people walking around with smiles on their faces. We really feel we have cracked it.'
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