Of course I knew it was nesting birds making this noise. I’d read about storm petrels in books. So small, so smooth, they could nestle in the cup of a child’s hand, if you were ever to catch one.
Yet listening to their continuous mechanical thrum, the idea of feather, beak and beating heart making this noise is inconceivable. It’s as if they’re made of metal, with wired legs, hinges at the base of their wings and a spring inside their beak.
As they return from their day at sea they begin to swarm around the broch of Mousa. Their black darting bodies are more like bats than birds. The air moves and there is a flick of black. They are a sensation rather than a sight.
This is a field recording I made of them here. No engines or wind-up parts were used in the recording of this phenomenon.
© Shona Main 2013