Abstract
Monitoring is an essential component within the field of marine ecological research to help understand and manage marine ecosystems. The rapid developments in offshore wind energy and infrastructure, marine aquaculture, and nature conservation and restoration efforts, has driven a growing demand for marine ecology data to evaluate their impact and/or effectiveness. Traditional monitoring methods include for instance diver inspection, ship-based side-scan sonar and multibeam or use of industrial (work-class) Remotely Operated Vehicles (ROVs). These methods work well, but are often very costly. Rapid advancements in small handheld Unmanned Underwater Vehicles (UUVs), along with innovations in sensor and remote grab technologies, have the potential to create new marine monitoring possibilities. UUVs, often described as mobile platforms, come in various forms. This report focuses on inspection-class ROVs and smaller Autonomous Underwater Vehicles (AUVs). Gliders and Extra Large Unmanned Underwater Vehicles (XLUUVs) are not included in the scope of this report, as their operation requires more specialized resources and infrastructure. Compared to work-class ROVs and larger AUVs, these smaller vehicles are lighter, easier to operate, and typically do not require launch systems. They also do not need large specialized vessels making deployment more flexible while reducing operational and monitoring costs. Equipped with add-ons such as robotic arms and diverse sensor types, these platforms can offer accessible and cost-effective monitoring solutions, even in challenging environments. Despite their potential, the full range of applications for these platforms remains largely unexplored in marine research. Therefore, this report examines available technologies, sensors, and UUVs, alongside case studies, user perspectives, and operational challenges to support the development of effective monitoring frameworks. Furthermore, the report includes a brief introduction to Artificial Intelligence (AI), specifically Computer Vision (CV) techniques, to illustrate how optical (video, photo, sonar, etc.) imagery from UUVs can be analysed. The goal of this project is to provide an up-to-date overview of innovative tools available for habitat mapping and biodiversity monitoring using: • Handheld UUVs: inspection-class ROVs and small AUVs • Sensors and acoustic techniques that can be mounted on mobile platforms • Artificial Intelligence: Computer Vision A general overview of inspection-class ROVs and small AUVs is provided in this report. We do not attempt to compare the various models of ROVs and AUVs, since many can do similar tasks and can be customised by adding add-ons such as sensors (e.g., cameras and sonar) or robot-arms. Therefore this report includes a chapter on add-ons with links to technical specifications on the manufacturers websites. Furthermore, since a lot of monitoring requires some form of data processing using AI, a small overview is given of the various options for image analysis. The practical use of ROVs and AUVs for ecological monitoring is demonstrated by a step-by-step approach presented in different user cases about monitoring biogenic and geogenic reefs in the North Sea, coral reefs in the Caribbean, artificial reefs and Nature Inclusive Designs (NIDs), and aquaculture. The annexes provide technical specifications of small ROVs and AUVs.