Fisheries Behavioral Ecology - Abstracts
Rose, C.S., A.W. Stoner, and K. Matteson. 2005. Use of high-frequency imaging sonar to observe fish
behaviour near baited fishing gears. Fisheries Research 76:291–304.
Abstract
A high-frequency imaging acoustic camera was used to observe the behaviour of sablefish (Anoplopoma fimbria) and Pacific
halibut (Hippoglossus stenolepis) around baited fish pots and baited hooks in the deep shelf environment (220–366 m depth) off
Oregon. The acoustic camera, tested to a distance of 9.7 m (11.5-15.6 m2 field of view), provided continuous high-resolution
imagery of approaches of fish to the gear, entry into pot tunnels, bait attacks, and escapes in conditions of darkness and high
turbidity. Fish inside and beyond the fish pot could also be observed. Fishes, including small individuals and “bait thieves”
(>20 cm), could be measured and tracked in the digital images. Concurrent observations with a low-light video camera and
infrared lighting yielded a field of view of approximately 1 m2, limited to just one side of the fish pot. A large proportion of
the video tape produced was unusable because of turbidity, and the patterns of fish movement around the pots and baited hooks
were poorly characterized by the video camera. The large field of view provided by the acoustic camera showed that a very
low percentage of sablefish and halibut approaching the gear were captured. Observations on different gear types, including
fish pots with and without tunnel triggers, provide insights into how acoustic camera imagery can be used to improve our
understanding of fish behaviour in the natural environment, to design increasingly selective and efficient fishing gear, and to
improve bait-dependent stock assessments.
Last updated
27 April, 2007
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