Three-dimensional underwater shape measurement of tuna longline

The installation depth of the hook in longline fishing gear has previously been measured with micro depth loggers. Research that assumes the catenary shape of longline fishing gear by a simulation based on these data has been done. However, it was not known whether the branch line was tangled with the main line or flowed with the current. In this research, an ultrasonic positioning system generally used to investigate the underwater behavior of marine organisms, and a buoy with a communications satellite, have been used, and the 3-dimensional underwater shape of tuna longline fishing gear was measured. It was possible to monitor changes in fishing gear in real time. The possibility of high precision measurement was suggested with future technical improvement.

Method for estimating buoyancy of midwater float required to standardize hook depth in pelagic longline

Effects of the gear deployment strategy and current shear on pelagic longline shoaling - ScienceDirect

Shark Depredation and Unwanted Bycatch in Pelagic Longline Fisheries by Western Pacific Regional Fishery Management Council - Issuu

Experimental and Numerical Analysis of Trolling Line for Hairtail Fishing

Flume tank and in situ trials for verification of static and dynamic methods for gear depth and underwater behavior of hairtail trolling lines

Life Sciences on X: Three-dimensional underwater shape measurement of tuna longline using ultrasonic positioning system and ORBCOMM buoy / X

PDF] Sinking depth of tuna longlines related to mainline materials in the North Pacific Ocean

PDF] Sinking depth of tuna longlines related to mainline materials in the North Pacific Ocean

Flume tank and in situ trials for verification of static and dynamic methods for gear depth and underwater behavior of hairtail trolling lines

PDF) A digital stereo-video camera system for three-dimensional monitoring of free-swimming Pacific bluefin tuna, Thunnus orientalis , cultured in a net cage

Bluefin Tuna Migration Explained

Depth Measurements of Tuna Longline by Using Time-Depth Recorder