Geoff Sample will spend up to 100 hours in a tiny camouflaged hide in a bid to be the first in Britain to record the call of the adult bird.
Mr Sample, 61, said: “I’ve had a fascination with golden eagles for most of my life. It’s no exaggeration to say this is a culmination of my life’s interest and life’s work.”
The freelance wildlife sound recordist has a huge collection of up to 30,000 individual birds’ calls from all but a handful of the UK’s breeding species.
But the golden eagle is the one he really wants.
He said: “My grandfather used to live in Tomintoul and I got into eagle-watching. Generally, people say golden eagles are silent or make a feeble call.
“But over the last five years I’ve become aware there’s a particular loud call the golden eagles do.
“Last year I was in Sutherland watching a pair of golden eagles and heard the bird calling three times that week. It’s a repeated yelp. It brought out the wild spirit of the place.
“It was early in the morning. I’d just arrived, and I couldn’t believe it. I thought I’d hit the lottery jackpot.
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“I’m aiming to get a decent recording that conveys something of that feeling. I think this will be the first time this call has been recorded – the full call of a wild adult golden eagle.
“All the recordings I’ve heard [of golden eagles] were begging calls - young birds begging or the female calling for food - and this other call’s been overlooked.
“It seems to me the bird makes this loud call in two situations: the female or the male calling to its mate somewhere round the nest site and hoping it’s around.
‘The other situation is where the bird is irritated – if ravens are mobbing them, or crows. It’s swearing, I suppose.”
Mr Sample, of Wooler, Northumberland, estimates the project could cost up to £5,000, including golden eagle workshops for communities in the Cairngorms, Sutherland and Skye.
The former guitarist, who once ran his own London recording studio and mixed Jools Holland’s live shows - plans to camp out in Sutherland in May and June, cooking on a gas stove and with no mobile signal.
When the weather is good enough he will take to his domed hide, its floor base measuring just four feet square. Over three weeks, he will spend up to 100 hours in the hide, 150 metres from the microphones he hopes will pick up the call.
Mr Sample said the reason for his fascination with the birds was hard to put into words.
“It’s something to do with the way they use the landscape. The first pair I got to know, as a child in the Cairngorms, were very wary. When you came across a ridge a mile away, they knew. They saw me before I saw them, then they would keep an eye on me.
“They pair for life and they stay on the territory. They can live for 20 years. It’s the idea that they get to know that patch of land and imbue it with their presence. They’re the presiding spirit of their patch of country.”
To donate to the project, contact Geoff via his website, geoffsample.com.