What is a BRUV?
Read how we designed our own BRUVs an don't miss the links at the bottom to know more
BRUV stands for baited remoted underwater video, and it is a popular technique to obtain information not only about who inhabits the underwater realm but also about densities, human impacts, behaviour and size distribution of aquatic animals. In fact, stereo BRUVs mount two cameras instead of one, that following calibration of the visual field enable measuring anything that appears on screen. This is what we are using. In BELAS we teamed-up with the company GlowDive (by Carlos Villoch) to produce our own stereo-BRUVs. After some back and forth in the design, we came up to a version that is both resistant and light.
To maximize efficiency at sea we use four units simultaneously in the same location, separated by a minimum distance to ensure the independence of results.
Each unit contains two cameras mounted at an angle of around 7-8º and separated by a fixed distance. This setup enables the calibration of the field view, ultimately allowing us to measure the size of the fish recorded. Calibration is done in a swimming pool and processed using the free software Vidsync.
