Georeferenced 3D photogrammetry: a tool for monitoring finfish aquaculture impacts on hard seabed (RD152)

Project Outcome:

Sustainable growth of the aquaculture sector necessitates the adoption of stringent environmental regulations to preserve protected species and habitats in coastal marine and aquatic environments. This is especially the case for farms situated over hard-substrate seabed, which cannot be grab sampled, and for which no environmental standards currently exist.

The project successfully developed and validated cost-effective methods for underwater navigational accuracy, supporting semi-autonomous control of remotely operated vehicles (ROVs) for monitoring hard seabed environments. By integrating real time kinematic (RTK) and Doppler velocity logging (DVL) technologies, we achieved unprecedented navigational precision, enabling ROVs to conduct repeatable survey patterns and generate high-quality georeferenced 3D photogrammetry models. Automated analysis of these models improved monitoring efficiency, making the technology accessible to regulators and producers. Demonstration surveys on operational marine pen fish farms showcased the practicality of these advancements in working settings, confirming the project’s potential to revolutionise seabed monitoring for aquaculture impact assessments.

While hard-substrate sites have been identified as a regulatory gap which this project seeks to address, the methodologies developed also have the potential to be used in the monitoring of soft-substrate sites. If suitable metrics can be identified and used as environmental quality standards in these environments, the visual survey and modelling techniques described could ultimately replace the physically laborious and time-consuming grab-sampling currently required for environmental compliance. Tritonia will continue to work on developing this workstream.