Poster by: Eric Kingma
The pilot study explored the use of electronic monitoring (EM) in the shallow and deep set components of the Hawaiian pelagic longline fishery. EM systems, consisting of closed circuit television cameras, sensors (e.g., GPS, hydraulic pressure and winch rotation) and a system control box, were deployed on three vessels, simultaneously monitored with observers, for a collective total of about 320 sea days, 13 fishing trips and 182 fishing events. Overall, the equipment performed well, recording data for 99.2% of the time vessels were at sea. A key strength of EM is the continuous sensor data record providing very accurate temporal and spatial information on gear setting and retrieval activities. EM image reviewers were also able to reliably detect hooks deployed and retained catch. About 40% of the discard catch was not detected by EM image reviewers, because discard releases occurred outside the camera view.
Overall, EM species identifications were more general than by observers and most common species were identified from EM imagery. Detection of protected species by EM and observers was similar, with both detecting all sea turtles encountered and each missing one of three caught.
The shortcomings of EM for discard detection could be addressed by improvements to camera placements and harmonizing crew activities with the technology.