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Advantages and Applications of Novel “Video-Fishing” Techniques to Design and Monitor Marine Protected Areas

Mike Cappo, Euan Harvey and Hamish Malcolm

Australian Institute of Marine Science, TOWNSVILLE, AUSTRALIA

Theme: TH4

There is a need for non-destructive, non-intrusive techniques to monitor the diversity, abundance and biomass of fish and other motile fauna inside and outside the bounds of Marine Protected Areas. Underwater visual census (UVC) techniques are restricted to shallow water <30 metres deep and are biased by the presence and performance of a SCUBA team. The accuracy and precision of estimates of abundance and length (and hence biomass) of reef fish in such UVC can be vastly improved with use of stereo-video techniques. Traditional fishing techniques used to survey deeper fish can be destructive and severely biased by gear selectivity. The use of remote “video fishing” (with and without bait) offers rapid assessment capability, with the option of very precise and accurate length and biomass estimates when stereo-video pairs are used. “Video fishing” can also be used in combination with other traditional methods to enhance the scope and capability of monitoring programmes. This contribution briefly reviews the application of single and stereo-video techniques and reports in detail on the performance of a fleet of single Baited Remote Underwater Video Stations (BRUVS) in detecting spatial patterns of fish community distributions and abundance. Case studies from the Great Barrier Reef and Solitary Islands Marine Parks, and southern Western Australia, are presented. We conclude that remote video techniques offer a hybrid assessment tool with the advantages of both UVC and capture techniques, but appropriate sampling statistics must be developed if relative abundance is to be measured adequately.