In 1991, CCAMLR adopted Conservation Measure (CM) 25-03, which prohibits the use of net monitoring cables in the Convention Area following concerns over potential seabird mortalities, it applies to all trawling techniques. Technology has developed since the introduction of this CM and the trawlers currently involved in the krill fishery that use continuous pumping methods differ operationality from the fisheries that initially led to the establishment of it. The main change is that the part of the monitoring cable exposed to the air is considerably shorter and is attached to, or close to, the warp itself rather than being a separate, or third wire, between the warps. The nets can be deployed for several days using the continuous fishing method, trawl time is limited with wireless communication using trawl sensors due to battery capacity. The use of a monitoring cable allows for an increased data flow helping to improve fishing efficiency and catch reporting resulting in a reduction in ecosystem impact. Being able to reduce the number of times the net has to be set and hauled also increases crew safety. Some of the concerns regarding net monitor cables may be less significant now, and so vessels that use continuous pumping technology were permitted a derogation of the CM, allowing net monitor cable trials for the 2019/20 and 2020/21 seasons. This report presents the results from the 2020-21 fishing season (November 2020-October 2021) from three Norwegian flagged vessels (two side-trawlers and one stern-trawler) using the continuous pumping fishing method from CCAMLR Area 48. The study was undertaken in full compliance with the requirements of the CCAMLR Scientific Committee (SC) (SC-CAMLR-38, paragraph 5.14) and data were collected according to standard SISO protocols, with the addition of video monitoring. Abundance estimates of birds were also obtained. Seabird mitigation measures used on all three vessels were determined by ACAP best-practice guidelines. A combination of deck observations and video monitoring were used to observe warps and monitoring cables and a total of 1,839 hours of observations were made at sea, representing 7.1% coverage of the total fishing time. Four 15-minute video observations were performed at set times each day in addition to three standard deck observations. To increase coverage, 180 hours of onshore observations were also made from footage taken from Antarctic Endurance and Saga Sea during fishing from early April to early June, raising overall coverage to ~20% on one net during this time period. All sets and hauls were also monitored. A total of 304 contacts were observed, of which 187 were with the net monitoring cable, the remainder were with the warps, the mitigation measure or classed as unknown. There was only one observed mortality following contact with a trawl warp. In conclusion, this report demonstrates that for both types of trawlers (side and stern), the risk for seabirds in connection with interactions with the monitoring cable is minimal.
The greater efficiency and targeted fishing enabled by vessels using this continuous pumping method can reduce the climate footprint. We ask WG-IMAF to consider advising the Scientific Committee and the Commission as to revise CM 25-03 to allow the use of a net monitoring cable, with mitigation measures as requested by the derogation.