Trail of feathers

FOR a moment, nothing can be seen but bleak, thigh-high heather stretching into the distance. The steady drizzle is turning ugly, and up ahead Logan Steele is disappearing into the gloom of an all-too-typical dank June evening on the Perthshire moors.

Then they rear up like pantomime villains as Steele uses expertise gained over 30 years to locate their well-hidden nest. Four hen harrier chicks – two male and two female – raise themselves to their full height of around 30cm, puff out their chests and flap their wings while fixing us, along the line of their beaks, with what looks like a 'come and get us if you're hard enough' stare. About five weeks old, they can't run and they can't fly, so all they can do when predators come calling is try to tough it out like mini-Draculas.

With a smile on his face, Steele drops to one knee and gently picks the biggest one up in both hands to check its gender and its overall condition. As a member of the Scottish Raptor Study Group (SRSG), volunteers who spend their free time high on the moors in all conditions watching out for Scotland's birds of prey, it is a moment of triumph. Earlier this year, he had watched from a distance, tracking the aerial movements of the parent birds as they built their nest, then inspected the platform of twigs and spotted the shiny eggs. Ever since, he has been keeping an eye on the vulnerable chicks as they make their precarious journey towards adulthood.

Hen harriers, because they eat the grouse that so many Scottish estates depend on for income, are Britain's most persecuted bird. "It's rare to see four chicks in such good condition, and these should survive into adulthood as long as they are left alone," he says. "They have enough to contend with, with climate change and the destruction of their habitat. If you add persecution on top of that, they are really going to struggle."

The next hen harrier nest, about a mile away, over the hill near Loch Rannoch, is a case in point. In late May, Steele logged the presence of four similar eggs, concealed in the heather. By mid-June, when they should have hatched, there was no sign of either them or their parents. Not a trace of eggshell could be found, raising suspicions that they had simply been removed.

Hen harriers were first exterminated by Victorian gamekeepers, who labelled them 'enemy number one' because of their fondness for eating grouse chicks. By the end of the 19th century, they only survived on remote West Coast islands. After the Second World War, the expansion of forestry in the Highlands brought some cover and a partial return. By 2004, the RSPB had logged more than 600 pairs – the majority of them in Scotland. On the moorlands of England, only 15 pairs remain.

Although the trend is upwards, huge areas of Scotland remain virtually free of hen harriers, particularly the eastern Highlands and the Southern Uplands, coinciding neatly with the main commercial grouse moor areas.

It's the SRSG's job to try to ensure that, like other birds of prey recovering after generations of persecution (golden eagles, red kites, ospreys and sea eagles), hen harriers not only survive but spread their wings to new territories that should support thriving populations. Steele, a financial services worker from Aberdeen, has been a birdwatcher since he was eight years old and has spent countless hours lying in the heather monitoring the nests of birds of prey. When he looks at an OS map, he doesn't see hills, lochs and burns, he sees a patchwork of the 29 raptor nests on his extensive Perthshire patch.

Above Loch Rannoch, the peaks of Glencoe with their translucent patches of summer snow gleaming in the distance to the west, he turns from the harrier site to point towards eagle eyries on the mountains to the north and merlin nests in the Scots pines that line the gushing burns in the foreground. Nothing infuriates him more than seeing healthy young adult harriers fly the nest, never to be seen again.

"Hen harriers are the most persecuted birds in Britain because gamekeepers will not tolerate them," he says. "Not only do they eat grouse, but if they fly over a shoot when the season starts, the grouse will disappear very quickly. If you are a landowner who has spent a lot of money setting up a shoot for paying guests, you're not going to be pleased. Gamekeepers will lose their jobs.

"The birds are doing well in certain areas but not in others, and research has shown that those correlate with grouse moors. And nothing has really changed in recent years; if anything, it has got worse."

According to experts, the persecution of birds of prey comes in many forms. A heather bank in which a nest has been established is simply set on fire as part of 'moorland management'. Eggs are covered in oil, which suffocates a developing chick, stuck with needles or removed for disposal elsewhere. Chicks in the nest are stamped on, their carcasses buried. Adult birds are simply shot at close range, exploiting the hen harrier's tendency to try to defend its nest by attacking the attacker. It will swoop in close and at speed, then veer away at the last moment. Sometimes it will make contact, talons first, as Steele can testify.

As part of his job, Steele is licensed to approach the nests of birds of prey. Anyone else who does so without a licence and disturbs the birds in any way risks prosecution and a fine. It's impossible, however, to keep a constant watch on hundreds of nests. "We know some gamekeepers are doing it – they know we know they are doing it – but we have to be very lucky to catch them at it," he says. "It happens very quickly. I checked one healthy nest site on a Friday, and by Sunday the eggs had all gone. You watch others leave the nest for a new area, and then they just disappear off the radar. You see them go through the whole cycle – and then nothing."

Our time at the Perthshire nest is kept short to cause the minimum distress to the chicks while the parents are out hunting to feed their hungry brood. What is unusual is that although the male has now arrived and is 'alarming' – calling – above the nest to alert the mother, she has not appeared. The famous hen harrier attack does not materialise, and this is a cause for concern. Steele looks upwards, hoping she will flap into view. "If she hasn't appeared by now, it may be that something has already happened to her."

If the mother is dead, the chances of all four chicks surviving have already diminished as the male may not be able to feed all of them. As it is, three of the four are unlikely to survive more than a year anyway. "We are not against grouse shooting," Steele says. "It's a viable economic business in a rural area. But what we don't want is the persecution that comes with it. We just want the birds to be left alone."