St Kilda – an island on the edge of the climate crisis?

A new Climate Vulnerability Index (CVI) Assessment for St Kilda World Heritage Site was published last month by Historic Environment Scotland (HES). St Kilda is one of seven WHSs in Scotland and the only one inscribed as a Mixed Site, for both its natural and its cultural heritage.

60 km west of the Outer Hebrides in the stormy Atlantic, St Kilda rings with the sounds of dense seabird colonies in the summer. Surrounding waters support a diversity of marine habitats and these rich ecosystems bring the birds which once supported the people of the islands. St Kilda was inhabited for at least 4,000 years, its inhabitants harvesting seabirds for food, feathers and oil, as well as farming and raising livestock. The last islanders were evacuated in 1930 as their way of life was no longer sustainable but they left behind the physical evidence of their unique culture.

Climate change is one of the fastest-growing threats to World Heritage Sites worldwide and since 2019 HES has been working with their World Heritage partners to carry out CVI assessments across six of Scotland’s WHSs. For St Kilda they worked with owners and managers from The National Trust for Scotland and the creators of the CVI tool from James Cook University in Australia, supported by a Royal Society of Edinburgh Research Network Grant.

The CVI methodology was designed to rapidly assess vulnerability to climate change, evaluating current and potential impacts upon the factors that comprise the Outstanding Universal Value of a WHS.

While climate change has many current and projected impacts on St Kilda, the CVI assessment identified three key stressors:
– Increasing temperatures both on land and of sea water
– Changes to storm intensity and frequency
– Changes to ocean currents
These factors may potentially interact to compound their effects on the WHS.

Climate change will threaten some elements of the WHS more than others. Of particular concern are changes in available food resources for seabirds, as well as the impact on the cultural landscape from increased visitor numbers and storm-related damage. The island’s natural heritage was judged to be more vulnerable, mainly due to the spatial scale of climate impacts, while there are more options available to manage threats to St Kilda’s cultural heritage.

Click here to read the full report.