The mystery of Scotland's 'disappearing' eagles
It was late January when Fred disappeared. A young golden eagle, he would have had characteristic brown-gold feathers and of course that hooked bird-of-prey beak, bright lemon-coloured and black. Fred had been monitored near the Pentland Hills – not far from Edinburgh in Scotland.
The previous summer, Ruth Tingay, from conservation group Raptor Persecution UK, had watched as a colleague fitted a tag to the raptor at its nest site. She had been tracking Fred’s movements ever since.
去年夏天，来自“英国猛禽迫害”（Raptor Persecution UK）护卫队的汀盖伊（Ruth Tingay），继她的同事在鹰巢中为这只金雕安置了跟踪器后，一直在关注其行踪。
The trip to the Pentlands was the furthest he’d been.
“He’d only been gone from the nest site for three or four days,” she says. It was on 20 January 2018 when the signal went blank.
Then, unexpectedly, it returned four days later. But in a very strange place: about 10 miles out at sea near St Andrews. Quite far north-east from where Fred’s signal had last been seen, did it reveal that Fred had been killed and dumped at sea?
Conservationists despaired. Another disappearing golden eagle that seemed to have met a suspicious end. Raptors are sometimes killed by humans, but the perpetrators are notoriously difficult to catch. Police Scotland are now investigating Fred’s case.
Scotland is home to various raptor species, but golden eagles (Aquila chrysaetos) are perhaps the most iconic. While their population in Scotland is generally doing well, they struggle to survive in some areas, particularly in the south of the country. One project is hoping to change that by translocating birds there from the highlands.
Other raptors are having an even tougher time – notably hen harriers, numbers of which are clearly declining. These birds, too, are sometimes killed illegally.
But who is attacking Scotland’s raptors? And what, exactly, happened to Fred?
More signs of suspicious activity in Fred’s case were revealed after Raptor Persecution UK got in touch with the manufacturer of his tag. It had been set up to record GPS coordinates for the bird and also connect to nearby mobile phone masts. Ordinarily that mobile network data wouldn’t have been available to the conservationists, but the tag maker was able to provide access.
The results were startling – during that period of absence late in January, it looked as though Fred had travelled east seemingly along a road, south of Edinburgh, and then north over the Firth of Forth and out towards St Andrew’s.
“It showed a pretty clear direction of travel up to the North Sea,” says Tingay. The tag hasn’t transmitted any data since those last data points were collected. And it isn’t known whether it was still attached to Fred at the time of these mysterious movements, or whether it ultimately sank to the bottom of the sea. The trail, in other words, has gone cold.
“There are so few breeding golden eagles in south Scotland so he was an important bird,” says Tingay. “To lose him so soon after he left his natal [area]… is pretty shocking really.”
The strange movements of Fred are “absolutely undoubtedly” a result of human interference, says Ian Thomson at the Royal Society for the Protection of Birds (RSPB).
“We’ll probably never know exactly how it happened,” he adds. Thomson has been monitoring raptor killings in Scotland for years. He says there is a large weight of evidence linking the deaths to areas where grouse moors exist. There have been cases in which gamekeepers have killed raptors as a means of preventing them preying on grouse – which they need to retain in large numbers for the game shooting season.
Prosecutions are rare, though, and blame levelled at gamekeepers often proves controversial. According to a spokesman for the Scottish Gamekeepers Association, the body has suspended six members over five years for wildlife crime offences.
“As an organisation, we advocate only legal means to resolve species conflicts,” he adds. Part of the problem for anyone monitoring raptor deaths is that whoever is killing birds of prey seems to have become more determined to cover their tracks in recent years, explains Thomson.
For example, he says the RSPB has evidence to suggest that raptors like golden eagles appear to be shot more often than they used to be – perhaps so the perpetrators can easily remove the carcass so less evidence is available to investigators.
“In the last six or seven years there does appear to have been a significant move away from the illegal use of poisons,” adds Thomson.
Logan Steele, of the Scottish Raptors Study Group, agrees. “We’re finding a lot of birds with satellite tags disappearing, no bodies found,” he says.
The group has tagged in excess of 150 birds in recent years, he adds. He’s currently monitoring data from a hen harrier that has just started to move about the country more widely. “I’m hoping it will survive,” he says.
While there are those who would harm Scotland’s magnificent birds of prey, there are plenty of others working to protect these creatures wherever they can. Sadly, their work is still cut out for them, says Tingay: “It’s hard to know whether it’s improving or not but I certainly haven’t seen any evidence of a decline in persecution.”