Midnight trip to Mousa

It was 10.30 pm when we stepped aboard the small boat to Mousa. The sea around the harbour was almost completely still, its glass-like surface a window to the underwater world, details of rock and seaweed still clearly visible despite the lateness of the hour.

Haar clung to the edges, bringing the horizon closer and obscuring the divisions between land and sea.

I was going to the island of Mousa with my son Rohan. I have made this trip several times, for me it is one of Shetland’s most memorable experiences, but this was Rohan’s first time.

Mousa is home to 12,000 storm petrels, around 40% of the UK population. A distant relation to the albatross, these tiny birds spend their winter months around the coast of Africa, and in summer thousands come to Mousa each year to breed.

Due to fears of predation, these birds usually return to their nests under the cover of darkness, but in Shetland at midsummer, there is near constant daylight. This means that during the hours around midnight, hundreds of birds arrive at the same time.

Our group gathered by a stone cottage next to the pier and the guide explained its history as a fishing station, then as we walked along the winding path, he pointed out the remains of houses and watermills. We heard stories of fish, trade, lairds and smuggling, insights into lives lived here before, his words bringing the rugged landscape and crumbling walls to life

The light slowly faded, sea and sky becoming silver. The calm sounds of curlew and snipe were suddenly interrupted by the shrill cries of oystercatchers, their piercing call reverberated between sea and sky as they flapped in wild circles, voicing their objections to a threat I couldn’t perceive.

I scanned the hills around us, wondering if it could have been an otter that upset them before noticing the shapes of sheep in the distance and realised it was probably one of the flock straying too close to a nest.

As we followed the path to the broch the sheer size of it, silhouetted against the sky took my breath away.

The broch at Mousa has been part of the coastline for 2,000 years, witness to centuries of changes to lives and landscapes. It features in Norse sagas,as a sight of siege when Earl Harold’s mother was captured and imprisoned within its walls and as a place of safety, providing refuge to an eloping couple who became shipwrecked. It’s identity as the best preserved broch in the world means it is being considered for UNESCO world heritage status.

We stopped close to the tower and gathered around to learn more about its current inhabitants, because thousands of years after the last humans made use of this place, it is still home to somebody. This is where the majority of the islands' storm petrels nest.

They have incredible survival strategies. The birds, on their search for food, can travel hundreds of miles, regularly leaving their nests for days at a time. While incubating an egg, birds take it in turns to stay on the nest while the other searches for food.

The bird on the nest can lose 20% of its body mass. Should the partner be away too long, and the remaining adult face starvation, they may have to go fishing, leaving their egg, alone and exposed. Amazingly, the chick inside the egg can survive several days while both parents are away.

Once hatched, the chick retains this ability to survive. When short of food, the chick can enter a state of torpor to conserve energy. Often appearing dead to worried human observers, a few drops of fish oil provided by returning parents, is enough to revive them.

As he spoke, the guide’s affection towards these birds was clear, through sharing his life with the petrels, his respect and admiration for them had grown.

The first fleeting shapes began to arrive on silent wings. I stood close to the broch looking up, silhouettes of birds filling the luminescent sky, flitting around the ancient walls.

Rohan, who had until this point been chatting excitedly to me about the sheep, seals and the broch was suddenly quiet. He stood still as the birds flew around his head then reached out and touched the stones. I placed my hand next to his. The smooth rock felt cold, and I wondered how many hands have touched these walls.

The presence of history was all around, the past close enough to touch. As the night grew darker, more and more birds joined the dance. There were sounds of scrabbling as they landed clumsily against the walls, before disappearing through gaps between the stones.

Birds were everywhere, we were surrounded.

Some swooped surprisingly close, the wind from their wings the only motion in the still night air. The returning birds caused the chicks in the nests to call out, a strange churring sound, that made it feel as if the walls themselves were vibrating that the broch had become a living being.

As we followed the path back towards the boat, a warm glow on the horizon signalled the start of sunrise. The stone walls we passed, that had stood silent earlier that evening, now reverberated with the sound of storm petrels.

We stood for for a moment listening to the song of a tiny bird, a worldwide traveller and born survivor, each one incubating an egg, from which a new life will soon emerge.

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