If someone told you it’s possible to get up close to Bronze Age history on St Kilda, you might assume they’re referring to an archaeological site.
But in fact, they could be talking about sheep. Living sheep.
The Soay sheep on St Kilda resemble sheep breeds that date back several thousand years. Physically and genetically they’re closer to wild sheep, like the mouflon, than to modern domestic breeds.
Like other ‘primitive’ sheep, they behave differently to domestic sheep. Rather than flocking, they scatter; and rather than needing to be sheared each year, they naturally moult (or ‘cast’) their top woollen coat.
They’re also tiny in comparison. The average mature Soay ewe weighs around 24kg and the average ram around 38kg – about a third of the size of most modern farmed sheep.
Apart from in early summer when they’re casting their coats and looking dishevelled, they’re beautiful too, ranging in colour from chocolate to ginger and even piebald. And they’re resilient. They’ve survived for hundreds or thousands of years on the uninhabited, storm-swept island of Soay, and more recently on the island of Hirta as well.
Sheep and the St Kildans
We don’t know how or when Soay sheep first came to the St Kilda archipelago, but it was probably around 3,000 to 4,000 years ago.
There are various accounts over the centuries of St Kildans rowing across from Hirta to Soay to gather wool or to catch the sheep (with great difficulty and athleticism) for meat.
On Hirta itself, the St Kildans kept their own sheep for wool and mutton.
Long ago they turned to more pliable breeds such as Blackfaces, although these were often cross-bred with Hebridean breeds. The darker wool gathered by the islanders on Soay was often mixed with the paler Hirta wool for colour contrast.
After the evacuation
When the St Kildans were evacuated in 1930, their sheep on the main island of Hirta were removed as well, leaving the island sheepless. But the Marquess of Bute, who bought St Kilda in 1931, thought that a flock of Soays would benefit Hirta. A small group of St Kildans returned to Soay and managed to catch 107 sheep of mixed age and sex, lowering them down the precipitous cliffs by rope or even carrying them down roped to their backs and fronts.
Like the sheep on Soay, the translocated sheep were unmanaged on Hirta, although various research teams have monitored them since 1955. As a native population without predators or competitors, they’re invaluable for researching primitive breeds, population dynamics, evolution, genetics and ageing.
This research shows the number of Soay sheep on Hirta has risen steadily since the 1950s. As with any wild animal populations, the numbers fluctuate annually, but the current Soay Sheep Project, running since 1985, has recorded a gradual steady upwards trajectory. Recent numbers show 1,500 or more sheep each year.
One factor in this may be climate change, with warmer temperatures increasing the grazing available in the winter months.
The lifecycle of the sheep is as natural as can be, with many of them dying close to where they were born. Their bodies enrich the soil where they die to sustain future generations. Researchers have tracked the longevity of the sheep, recording ewes reaching age 13 or more. Soay Sheep Project figures show that, generally, 10–20% of the ewes are aged 7 and above. By contrast, domestic sheep are usually only kept until 5 or 6 years old, and lambs for less than a year.
Cultural and natural heritage importance
For visitors to St Kilda, the Soay sheep certainly add to their experience of the archipelago. Susan Bain, Property Manager for St Kilda, says ‘It’s a joy to see them grazing in their natural groups, and to see the lamb gangs running and playing across the Hirta landscape in summer as they learn about the world. Later on in autumn, when the sheep have piled on their weight and their coats have grown back, it’s fascinating to see the rams’ behaviour change as the rutting season approaches.’
Though the sheep are not managed by people, they’re accustomed to our presence around Village Bay and are very relaxed about it.
But the sheep’s importance for St Kilda goes well beyond their attractiveness for tourists and their interest for science. Susan explains: ‘St Kilda is a cultural landscape, not just a natural landscape. Everywhere you look on Hirta, there’s evidence of people in the landscape; the Soay sheep, by grazing and fertilising it, help to conserve its look and ecology. They’re part of the cultural and natural heritage that makes St Kilda a dual UNESCO World Heritage Site – how you see them today is how they have probably lived for hundreds of years.’
