Using multibeam sonar to monitor animal behaviour and environmental interactions at marine renewable energy sites

Abstract

Marine renewable energy (MRE) enjoys rising popularity and interest with governments, industry, academics and the public. The complex interplay of MRE device placement and subsequent changes to animal behaviour needs to be assessed to minimise potential impacts and allow stakeholders, regulators and policy makers to make informed decision for future developments. Through use of multibeam echosounders (imaging sonar) we can observe and record animal behaviour at a fine scale (metres, seconds) drawing comparisons, establishing patterns and evaluating potential changes around MRE sites.
Being able to properly account for the impact MRE devices might have on the animals that utilise tidal-stream environments has been a major undertaking of marine scientists around the globe. Attention has been paid mainly towards the potential for collision risk and the introduction and increase of marine noise and its corresponding impact on marine mammal behaviour. Additionally, changes in fish school behaviour around MRE devices have also been observed. Advances have been made in understanding animal responses, but the lack of quantitative data, which is locked behind terabytes of recorded raw multibeam data, have limited definite and time-efficient proof and advice for stakeholders or environmental agencies in many cases.
This PhD project aims to examine the factors that influence the visibility of animal targets within a multibeam recording and to investigate the usefulness of evaluating animal behaviour through existing datasets recorded by low-resolution / low frequency multibeam instruments. Additionally, the accuracy of measurements for the detection and shape resolving capabilities of a new generation of multibeam (720/1200 kHz) are being investigated. This study aims to increase the understanding of this complex interplay of instrumentation and biological targets, and the importance of the accuracy and precision of measurements, to be able to make informed decisions about the potential effects MRE device placement might have on animal targets.

Date of Award	9 Feb 2026
Original language	English
Awarding Institution	University of the Highlands and Islands
Sponsors	Super DTP
Supervisor	Benjamin Williamson (Supervisor) & Barbara Morrissey (Supervisor)