Figure 5: Images taken from electronic monitoring systems on gillnet fishing boats. Boat names and GPS locations have been masked in these images
Video footage of 14 electronic monitoring system shots was reviewed to obtain catch composition data. Electronic monitoring system footage was reviewed by an AFMA observer with extensive experience in the gillnet fishery and thus was familiar with the species being caught. An independent data analyst (D&S Data Fix) with little experience in species identification was also asked to review the footage. Data from the inexperienced reviewer was not used for statistical analyses, but was used to compare results between video analysts. No pre-defined list of species was utilised.
The electronic monitoring system video footage was analysed using VLC Media Player at up to 4 times the speed of real-time and was subsequently reviewed on a frame by frame basis when a catch item was detected.
To best enable comparisons with catch recorded in logbooks and by observers, the electronic monitoring system analyst was instructed to focus only on species brought aboard in the net. This method was chosen to be consistent with that undertaken by at-sea observers. Of the three cameras fitted on board, the two cameras with view of the net as it passed between the net roller and the deck provided the clearest picture for species identification (Figure 6). Catch recorded as dropping out of the net before it reached the net roller (24 fish, 1 sponge) were not included in the dataset used for comparing catch composition analysis between at-sea observers and electronic monitoring system.
 
Figure 6: Example footage used by electronic monitoring data analysts to determine catch composition
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