Development of a stereo deepwater Baited Remote Underwater Video System (DeepBRUVS)

Marine researchers aiming to acquire composition and size-frequency information on fish assesmblages have successfully used Baited Underwater Video Systems (BRUVS) as a non-extractive alternative to more traditional sampling methods using nets or traps. In a monitoring study of gulper shark populations on the eastern Australian upper continental slope (300-700 m depths), it was necessary to re-design the BRUVS lander to enhance its capabilities. The DeepBRUVS lander was designed to allow self contained and independent deep water operation (up to 1000m), with an extended deployment period of up to six months. DeepBRUVS is equipped with a stereo video system, lighting, and a bait release mechanism that permits multiple replicate video samples to be taken. The data will be used to provide relative abundance and size data as indicators of the viability of gulper shark populations protected within fishery closed areas. This paper discusses the design, prototyping and deployment of DeepBRUVS. The mechanical design of the bait piston, and camera assembly are reviewed in detail, along with a discussion of free fall and ascent dynamics. Bait types, bait release schedules, and camera recording sequences are also reviewed. The paper also discusses potential future additions and system improvements.