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Advantages of BRUVs BRUVS confer several advantages over traditional sampling methodologies for surveying fish community composition, size, and relative abundance:
They can be used at depths beyond the safe limits of research diving.
They can be used in habitats where bottom nets are not appropriate (e.g. rocky habitats and around structures)
They are non-destructive so they can be used where extractive sampling is prohibited.
They are non-intrusive so they can capture large, mobile animals, such as sharks and rays, which would avoid scuba divers.
They give a permanent record that can be closely examined by scientists around the world for identification and shown to managers and fishermen alike for their own interpretation.
They give precise length and biomass estimates when used in stereo-pairs with analysis software.
They remove observer bias. They give a detailed image of the habitat types in the
sampling area.
Use of BRUVs in the UK
Baited Remote Underwater Video systems (BRUVS) are a method for sampling fish communities across a
broad range of depths and habitats.
The method utilises a pair of calibrated stereo high definition cameras deployed in a steel frame allowing
for underwater size analysis.
The use of stereo-video has become the most accu-rate way to size fish (without capturing them).
Studies to date by Swansea University with BRUVs in
the UK have assessed fish assemblages in UK Kelp Forests, Seagrass meadows and Modiolus beds
BRUVS software and calibration allows fish to be
accurately measured
High Definition Canon video cameras and underwater lights allow fish to be identified to species level
Assessments are undertaken at night utilising a bank
of underwater lights
Swansea university has two BRUV systems and has experience of running BRUV surveys in UK coastal
and offshore environments
BRUV Software
Swansea University utilises calibration and analysis software from SeaGIS Pty Ltd
Techniques used have undergone extensive peer review
Example Uses of BRUVs
BRUVs surveys can be used for assess-ments and monitoring of fish around
coastal and offshore structures (e.g. Wind farms, Marinas, and Oil & Gas rigs)
BRUVs surveys could be used for Environ-
mental Impact Assessments and environmental monitoring
For further information or to obtain a quote, please contact: Dr Richard Unsworth or Dr Ruth Callaway [email protected] or [email protected] Biosciences, Wallace Building Swansea University Singleton Park, Swansea, SA2 8PP Tel: +44 (0) 1792 602133
Stereo Video Assessment of Marine Fish Assemblages around Offshore Renewables
Researchers at Swansea University are utilising stereo Baited Underwater Video systems (BRUVs) to monitor and assess fish
assemblages in UK coastal and marine waters
Extensive BRUV surveys have been conducted in Zostera ma-rina meadows in Porth Dinllaen, North Wales (Picture: R. Holt)
Pollock attracted to Bait at Lundy
BRUVs can sample fish around marine renewable structures
