Too few oysters, too many deer. Highlands Rewilding’s Fourth Natural Capital Report
Highlands Rewilding’s fourth annual natural capital report details a wide array of monitoring techniques deployed across three highly surveyed open air laboratories.
The report's findings demonstrate that land which contains incredible natural diversity would still benefit from significant biodiversity improvements, particularly by reducing deer numbers and proactive coastline restoration. The unique depth and breadth of this data collection and analysis makes a significant contribution to understanding patterns of biodiversity and the embryonic natural capital market in Scotland, helping ensure this market develops to encompass high quality and consistent monitoring, vital for reversing current biodiversity loss.
The report focuses on a year of baseline biodiversity monitoring at the Tayvallich estate on the west coast of Scotland, an area renowned for its natural beauty, along with monitoring and restorative updates from its two other Scottish estates, Bunloit, on the banks of Loch Ness, and Beldorney, in Aberdeenshire.
Download a PDF of this report here.
A year of intense ecological surveying has revealed:
Tayvallich estate contains incredible natural diversity with a highly complex pattern of vegetation that is related to the equally complex topography of this area and sympathetic management in the past. This year of baselining has shown the distinctiveness of this mosaic of habitats, home to many species of special conservation importance and concern, with this year’s surveys recording 17 birds on the Red List of conservation concern, 31 on the Amber List, and surveying one of the few remaining strongholds of the rare and protected Marsh Fritillary butterfly.
Despite this, some of Tayvallich’s marine habitats are in desperate need of restoration. Loch Sween Marine Protected Area (MPA), including Tayvallich, is the only MPA in Scotland designated for the resident native oyster population, one of only three recorded oyster habitats in Scotland. While the whole loch has not been surveyed, the surveying presented in this report suggests that the intertidal population of oysters at this site has crashed in the past decade to such an extent that they can be considered functionally extinct.
Scotland needs to cull more deer. Across all three estates, despite recent increased deer management in place, thermal drone surveys have shown that deer densities are up to ten times higher than that which would allow natural regeneration of native woodlands, including Temperate Atlantic Rainforest. The report details Highlands Rewilding’s increased focus on deer management to enhance restoration efforts, with a particular focus on reducing the very high numbers of non-native sika deer.
The report also details the successful reintroduction of the hairy wood ant—a species previously lost to the area, the monitoring of wild boar populations, the planting of 60,000 native broadleaf trees across the rewilding sites, and the recording of over 18,000 invertebrates since 2022, and over 2000 birds in the past year alone.