Grazing and biodiversity in the uplands

The Scottish Biodiversity Strategy sets objectives for maintaining and enhancing the species and habitats for which Scotland is renowned.
Achieving this demands:-

• A detailed understanding of the interactions between key species and between trophic levels.
• A balance between the legitimate management objectives of the private landowners and the public policy objectives.

Grazing by free-ranging deer and domestic sheep is a key driver of habitat condition and is undergoing large changes because:

• Deer populations have been increasing in response to climate change. Conversely,
• Sheep numbers are being reduced in response to changes in the agricultural subsidy.

Understanding these changes is central to predicting the consequences for biodiversity objectives.

Our research investigates whether potential biodiversity benefits of reduced sheep stocking rates may be counteracted by increasing deer populations.
This understanding is central for developing sustainable grazing management strategies. We are focussing on four main questions:

1. How have deer populations responded to the environmental change experienced in different parts of Scotland?
2. What is the relative impact of sheep and deer grazing on the condition of priority habitats?
3. What are the consequences for biodiversity of grazing by sheep and/or deer?
4. How can conservation objectives be reconciled with the sporting and commercial objectives of private landowners?

Initial results demonstrate that:

• Sheep grazing is consistently associated with grazing impacts and that heath communities are more susceptible to grazing.
• Increasing deer densities is likely to increase heather utilisation; and reduce species heterogeneity between areas.

These results will help inform sustainable grazing management strategies that consider both public and private management objectives.

Related research

This research has facilitated additional research including three RERAD flexible fund projects (deer movements, diffuse deer impacts and deer health and welfare) and added value to the RELU funded project on Collaborative Deer Management.