Baited remote underwater video

Summary

Baited remote underwater video (BRUV) is a system used in marine biology research. By attracting fish into the field of view of a remotely controlled camera, the technique records fish diversity, abundance and behaviour of species. Sites are sampled by video recording the region surrounding a baited canister which is lowered to the bottom from a surface vessel or less commonly by a submersible or remotely operated underwater vehicle. The video can be transmitted directly to the surface by cable, or recorded for later analysis.

Divers inspecting a Stereo BRUV during sea trials by the South African Environmental Observation Network
Stereo BRUV prototype deployed at the Tsitsikamma National Park Marine protected area
Stereo BRUV prototype on trial at Rheeders' Reef, Tsitsikamma
Blue shark at Bremer Marine Park

Baited cameras are highly effective at attracting scavengers and subsequent predators,[1] and are a non-invasive method of generating relative abundance indices for a number of marine species.[2]

As a non-extractive technique, it offers a low environmental impact way of understanding changes in fish numbers and diversity over time. BRUV surveys were developed in Australia, and are now used around the world for a variety of projects. This is a low budget monitoring system that is less reliant on the availability of skilled labour and may make sustainable monitoring more practical, over the long term.[3]

There are two main types of remote video technique which have been used to record reef fish populations. They can both be left free standing without the need of an operator. The first system uses one downward looking camera (D-BRUV), and the other uses either one (mono) or two (stereo) horizontally facing cameras (H-BRUV),[4] and may use underwater lighting to illuminate the target area. Stereo BRUV recordings can use software analysis to determine the size of specimens.

The colour of the lighting used for video may influence behaviour of the target species.[5]

References edit

  1. ^ Wilson RR Jr, Smith KL Jr (1984) Effect of near-bottom currents on detection of bait by the abyssal grenadier fishes Coryphaenoides spp., recorded in situ with a video camera on a free vehicle. Mar Biol 84:83–91, Henriques C, Priede IG, Bagley PM (2002) Baited camera observations of deep-sea demersal fishes of the northeast Atlantic Ocean at 15–28° N off West Africa. Mar Biol 141: 307–314, in Raymond, Erika H. & Widder, Edith A.Behavioral responses of two deep-sea fish species to red, far-red, and white light. Marine Ecology Progress Series, Vol. 350: 291–298, 2007 doi:10.3354/meps07196
  2. ^ Brooks, Edward J. Sloman, Katherine A. Sims, David W. Danylchuk, Andy J. (2011) Validating the use of baited remote underwater video surveys for assessing the diversity, distribution and abundance of sharks in the Bahamas Endangered Species Research, Vol. 13: 231–243, doi: 10.3354/esr00331 https://www.academia.edu/718540/Are_baited_remote_underwater_video_surveys_BRUVS_an_alternative_to_conventional_longline_surveys_for_determining_the_diversity_and_relative_abundance_#
  3. ^ Baited remote underwater video (BRUV) survey of False Bay’s icthyofauna http://www.saeon.ac.za/enewsletter/archives/2013/february2013/doc01 accessed 3 June 2013
  4. ^ Tim Langlois, Pascale Chabanet, Dominique Pelletier, Euan Harvey (2006) Baited underwater video for assessing reef fish populations in marine reserves, SPC Fisheries Newsletter #118 – July/September 2006, 53
  5. ^ Raymond, Erika H. & Widder, Edith A.Behavioral responses of two deep-sea fish species to red, far-red, and white light. Marine Ecology Progress Series, Vol. 350: 291–298, 2007 doi:10.3354/meps07196