Video observation of the FMA 1 bottom longline fishery in 2020–21 and 2021–22

Video observation was used to monitor seabird captures in the Fisheries Management Area (FMA) 1 bottom-longline fishery. The observations were made during the 2020–21 and 2021–22 fishing years, from November 2020 to May 2022. This programme (typically referred to as the ‘petrel project’) extended previous video monitoring of this fishery that began during the 2016–17 fishing year. Existing camera deployments, on eight voluntarily participating vessels, were used to collect the footage. The participating vessels set 35% of the total hooks in FMA 1 bottom longline fisheries during 2020–21, and 40% of the total hooks in these fisheries during 2021–22. The statutory Electronic Reporting (ER) data were used to define haul periods, and hauls were randomly selected for video review. Any hauls that had fisher-reported captures were also selected for review. There were also a small number of hauls that were reviewed for other reasons. Overall, for the 2021 summer season (November 2020 to May 2021), 441 (12.1%) of bottom longline fishing events in FMA 1 were reviewed, and for the 2022 summer season 211 events (8%) were reviewed. Additionally, 252 (3.7%) of bottom longline fishing events occurring from June to October 2021 were reviewed.

If any seabird captures were found during the primary review, the capture events were passed to an expert reviewer for further review. There were a total of five reviewers reviewing footage from the 2020–21 fishing year. In addition, during the 2021 fishing year, any hauls with capture events were passed for secondary review from at least three other reviewers. This allowed variation in the skill of the reviewers at detecting seabird captures to be quantified. Based on expert review of the video footage, there were 176 seabird captures during 2021, and 21 during 2022. Around a third of the seabird captures were dead (26.7% of captures during 2021, and 66.7% of captures during 2022). The highest number of captures recorded from a single vessel was 71 captures. Flesh-footed shearwater (Ardenna carneipes) was the most frequently caught species (139 captures during 2021, and 19 captures during 2022), followed by black petrel (Procellaria parkinsoni; 35 captures during 2021, and 2 captures during 2022). A fluttering shearwater (Puffinus gavia) and a sooty shearwater (Ardenna grisea) were also captured, both in 2021. The secondary reviewing established that there was high variation in reviewer skill. Two reviewers detected over 90% of the seabird captures; however, one reviewer detected fewer than 50% of the captures.

A model was used to estimate the total captures of black petrels and flesh footed shearwaters using the video-review data. There were an estimated 40 (97.5% c.i.: 14 to 79) black petrel captures in all bottom longline fishing in FMA 1 during the 2021–22 fishing year, and an estimated 159 (97.5% c.i.: 56 to 392) flesh-footed shearwater captures in the same fisheries and period.

During the 2020–21 and 2021–22 fishing years, there were 257 seabird captures reported by fishers from bottom longline fishing within FMA 1. Of these captures, 218 were reported from vessels participating in the video monitoring trial and only 39 seabird captures were reported from other vessels. The rate of fisher reported seabird captures was close to ten times higher on vessels that were participating in the petrel project.