NatureScot Research Report 1275 - Time series analysis to determine change in maerl beds.
Abstract
This report evaluates methods for monitoring the recovery of maerl beds, a sensitive and declining habitat protected in several Marine Protected Areas (MPAs) in Scotland. Commissioned by NatureScot, the study focuses on two case study areas-the Isle of Arran and Wester Ross-and explores the use of semi-quantitative species data from drop imagery surveys to detect changes in maerl bed communities. The report highlights the need for standardized data collection and analysis methods to detect community changes and assess the effectiveness of management measures over short timeframes. It also identifies challenges, such as insufficient sample replication and the influence of seasonal and environmental factors, which can complicate temporal comparisons. Key recommendations include a standardized sampling design, appropriate survey methods, and long-term, repeatable data collection to reliably monitor maerl bed recovery and assess management impacts. The report emphasizes the importance of clearly defined monitoring goals and experimental design to ensure meaningful and statistically significant results in future maerl bed monitoring programs.