Interview: Alyth McCormack - Nesting instinct

Hunting the gannets, puffins and fulmar that made up their notoriously pungent diet was a skill the islanders' lives depended on, and boys started at the age of four. These audacious acrobatics amongst hidden ledges and wind-battered crags were how the St Kildans survived for so long in this wild place, surrounded by nothing but birds, churning grey seas and stretched-out skies.

In St Kilda, Island Of The Birdmen, a large-scale multimedia opera coming to Edinburgh International Festival, these skills are re-imagined as an awesome aerial ballet, filmed on the island and projected on to vast screens onstage. Dancers suspended on ropes drop from and bounce off vertical rock faces. Cameras sweep over, around and up Stac an Armin and Stac Lee, the hunting grounds of the birdmen. In front of these screens, the small, lone figure of Alyth McCormack, representing the spirit of the islands, sings traditional songs from St Kilda, guiding us through the stories of life, loss and finally evacuation on the morning of 29 August 1930 when the last 36 inhabitants of St Kilda boarded the boat for the mainland.

"One of the things they used to say about the St Kildans when I was growing up was that they had claw feet," she tells me when we meet in Glasgow's West End. Petite and dark-haired, McCormack is from Lewis, 40 miles east of St Kilda. She's a bit of a glamour-puss, dressed to the nines to meet the photographer and later sending me her wedding photos because her wedding dress was designed for her by Harris Tweed, "an industry that my grandpa worked in and that has been suffering over past years".

"Two of their toes were clawed, we were told, and that was apparently how they got to the birds and their eggs," she goes on. "The St Kildans came from Lewis and Harris originally, they think. I remember meeting families who were from St Kilda and wanting to see their toes. I couldn't stop looking at their shoes." She laughs. "I'm still not sure if it's true or not."

McCormack has never been to St Kilda, though not for want of trying. "I've tried a few times," she sighs, "but the weather always turns out to be too bad. You can see why everything the St Kildans did was governed by the weather."

Now that she has appeared in this ambitious production in France and Belgium, and will soon be in Edinburgh for her EIF debut, she is more determined than ever to make the notoriously rough crossing. "I have to go now," she says. "When you see the film of the cliffs circled by birds in this production you feel like you're there. I'll be more nervous performing in Edinburgh though. My first singing teacher, who taught me in primary school, is coming from Lewis to see me."

It's astonishing that it has taken this production until now to come home. The opera may be new to Scotland but St Kilda has already been seen in five European cities in 2007. It was quite an event too. Each performance took place at the same time, linked by live satellite to St Kilda and webcast on the BBC.

In Edinburgh we're getting the Belgian version, directed by Thierry Poquet and featuring actors, musicians, dancers and choirs. He auditioned McCormack to appear in the film he was shooting of St Kilda that is spliced with archive footage but was so taken with her that he asked her immediately afterwards to star in the production itself. What does she think he saw in her? "I think he liked my singing," she says, mock-bashfully.

St Kilda, Island Of The Birdmen uses contemporary and traditional music, which suits McCormack down to the ground. McCormack sings in Gaelic and English, is classically trained, as influenced by the minimalism of Steve Reich as she is the Gaelic ballads of the north-west, and she interprets old songs and new. Justin Currie of Del Amitri wrote the title track of her latest album, People Like Me, and it firmly establishes McCormack as a genre-straddling talent, mixing folk with sophisticated pop and jazz arrangements. She even dropped the McCormack, becoming the much more pop-sounding "Alyth", and one critic likened her sound to "post-era Bjrk".

She has since been touring the world. She has played the Carnegie Hall and the village hall, performed with fiddlers and samba musicians. She has sung in films such as Annie Griffin's Festival and performed with Scottish Ballet. "My mum listened to a lot of classical music and my dad liked jazz," she says. "A lot of the classical composers I love, like Dvorak, base their music on folk idioms. But my heart lies in traditional song. There is something very raw about it, and that's the influence of my upbringing. Growing up in the islands is a raw existence."

Like so many singers from Lewis, McCormack started out in the church choir. Religion is still so integral to Lewis that the recent decision to introduce Sunday ferry crossings from the mainland prompted an outcry. "I sang in Sunday school and our teacher at school used to take the Gaelic choir," she says. "That's where my father and mother started singing too." She started learning Gaelic songs and usually they were about the sea. Growing up in a house "where you could see the sea from every window", imagining the sense of isolation and the power of the weather to govern all decisions wasn't hard for her when it came to St Kilda.

"I know what that experience is like," she says. "I love being an islander but even today it has its challenges. You still notice things missing off the shelves in bad weather. I loved it when it was wild and windy because it always felt like the sea was protecting the island, not isolating it."

McCormack left Lewis to study classical music at Glasgow's RSAMD and eventually she had to decide between becoming a soprano or a traditional singer. "I'd always wanted to learn how to use my voice," she says, "but my first love was the songs I grew up with, even though I firmly believe the only way tradition survives is if it evolves. Everything has come from something else. Look at when The Rite Of Spring was first performed. It was booed from two bars in."

Two years ago she moved to Dublin to be with her boyfriend (the one she married in that Harris Tweed dress). He is a musician too – for six years before that she was with the virtuoso fiddler Aidan O'Rourke – and he plays drums on her album and in the Irish band Moving Hearts. Meeting McCormack in Glasgow, it's clear that she is missing home. "In St Kilda there is a lot about loss and the feeling of being displaced," she says. "I feel it at the moment myself. Moving to Glasgow from Lewis was like magic, suddenly being invisible, able to disappear into the crowd. Now I want to be out of the crowds. It has crossed my mind to come back."

St Kilda, Island Of The Birdmen, 15-17 August, Festival Theatre, 8pm, www.edinburgh-festivals.com