– by C. Morgan-Davies (SRUC)
Aimee Walker (SRUC/University of Glasgow) successfully passed her PhD viva in March and graduated in Glasgow in July 2026. Her PhD was funded by the TechCare project. Aimee’s thesis explored the use of Bluetooth Low Energy (BLE) technology as a precision livestock farming (PLF) tool for monitoring sheep in grazing systems. While PLF tools are widely used in intensive systems (e.g., pigs, poultry, dairy cattle), their adoption in sheep farming has been limited due to challenges like large grazing areas, sheep size, and cost constraints.
Her research involved developing a prototype BLE system and testing it through three main objectives:
- Characterising BLE signal strength and distance in outdoor environments.
- Assessing BLE for sheep localisation using multilateration and GNSS validation.
- Investigating BLE for monitoring sheep contact patterns and relationships, especially around lambing.
© SRUC
The key findings in Aimee’s thesis related to:
- Signal Calibration: BLE signal strength decreased with distance and was influenced by device height and sheep behaviour. Sheep posture affected signal detection and range.
- Localisation: BLE could localise sheep with moderate accuracy (mean error ~19–23 m). High reader density would be needed for effective coverage.
- Behaviour Monitoring: BLE effectively tracked ewe–lamb and ewe–ewe interactions. Contact patterns changed with lamb age and ewe lameness, offering insights into welfare and management.
Aimee’s work showed that BLE is promising for monitoring sheep behaviour and welfare, especially in detecting social interactions and potential issues. However, limitations in signal reliability and range mean it may be best used alongside other technologies for comprehensive livestock monitoring. Aimee’s PhD thesis is available here.
